Cellulose-Based Composite Hydrogels: Preparation, Structures, and Applications

  • Liying QianEmail author
Living reference work entry
Part of the Polymers and Polymeric Composites: A Reference Series book series (POPOC)


In this chapter, cellulose-based composite hydrogels were summarized in three categories according to the components. Synthetic polymer/cellulose composite hydrogels combine the advantages of synthetic polymers and cellulose. Soluble cellulose derivatives are feasible to construct the composite hydrogels with polyacrylamide, polyvinyl alcohol, polyacrylic acid, and so on. The composite hydrogels are normally applied as superabsorbents for heavy metal ions and dyes because the abundant functional groups in the hydrogels can act as binding sites. Due to most of the crosslinked polymeric hydrogels suffering from poor mechanical performance, low breaking strain, and sensitivity to fracture, cellulose nanocrystal can be combined into the hydrogels to enhance the mechanical properties significantly in order to obtain the mechanically strong, tough, or highly stretchable nanocomposite hydrogels. Natural macromolecules/cellulose composite hydrogels have a great potential for applications in tissue engineering, drug delivery, sensors, and purification for their excellent biocompatible, biodegradable, and nontoxic properties. Cellulose hydrogels have high mechanical strength and good permeability for liquids, gases, and electrolytes, the composite hydrogels which combine cellulose and extracellular matrixes are very promising scaf folds for the tissue repair and regeneration. Chitosan, alginate, and other polysaccharides are popular natural macromolecules for the composite hydrogels. Inorganics/cellulose composite hydrogels have recently received considerable attentions in both academic research and industrial application due to their excellent hybrid properties. Montmorillonite, clay, and bentonite are traditional inorganic minerals to fabricate the composite hydrogels as superabsorbents for water treatment, personal care, and agriculture. Nanoparticles of ZnO and Ag are also incorporated into the cellulose hydrogels to render the antimicrobial activity to biomedical materials. Recently, the novel cellulose-based composite hydrogels with graphene oxide, carbon nanotube, and carbon dots show potential applications in supercapacitors and biosensors.


Composite hydrogel Synthetic polymer Natural macromolecules Inorganic; Preparation Structures and applications 

1 Introduction

Cellulose composite hydrogels can be prepared from cellulose and macromolecules or inorganic materials with physical and chemical crosslinking. Physical hydrogels are formed by molecular self-assembly through ionic or hydrogen bonds, while chemical hydrogels are formed by covalent bonds [1]. Cellulose can take part in the formation of 3D network or act as reinforcement. Interpenetrating polymer networks (IPNs) are common structures for cellulose-based composite hydrogels, especially for synthetic polymer/cellulose composite hydrogels. IPNs can be divided into two types: sequential IPN and semi-IPN. For sequential IPN, cellulose is used as the first network, and the second network is formed by polymerizing in the presence of the cellulose network. When cellulose or its derivative is linear or branched in a crosslinked network, it is called as semi-IPN hydrogel [2]. Nanocellulose is an excellent reinforcement for both synthetic polymer and natural macromolecule hydrogels. Inorganic/cellulose composite hydrogels combine the advantages of both components which are very promising materials in biomedicals, tissue scaffold engineering, superabsorbent, and so on. The main purposes of incorporation of inorganics are reducing production cost, improving the properties, and rendering special features. This chapter discusses about cellulose-based composite hydrogels including synthetic polymer/cellulose, natural macromolecules/cellulose, and inorganics/cellulose composite hydrogels with the emphasis on the latter two categories.

2 Synthetic Polymer/Cellulose Composite Hydrogels

2.1 Water-Soluble Cellulose Derivatives

Naturally available cellulose is not water-soluble due to the hydrogen bonding between molecular chains; the strong intermolecular and intramolecular hydrogen bonds between the hydroxyl groups not only limit the water solubility but also lead to the poor reactivity of cellulose. However, water-soluble cellulose can be prepared by esterification and etherification reaction of the hydroxyl groups. Methyl cellulose (MC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), and carboxymethyl cellulose (CMC) are common water-soluble cellulose derivatives. The concentrated aqueous solution of cellulose derivatives can be crosslinked under irradiation to prepare cellulose-based hydrogels [3]. It is feasible to incorporate some synthetic polymers with cellulose to fabricate the composite hydrogels by chemical crosslinking via crosslinker and irradiation, physical crosslinking, and ionic crosslinking.

CMC is a representative cellulose derivative, which is manufactured by reacting sodium monochloroacetate with cellulose in alkaline medium. It is the most popular cellulose derivative to prepare the composite hydrogels with synthetic polymers. In situ free-radical solution polymerization of acrylate monomers onto CMC is one of main methods to introduce synthetic polymers into CMC hydrogels. By this method, acrylic acid (AA) [4, 5, 6], acrylamide (AM), and N-isopropylacrylamide (NIPAM) can be grafting polymerized on CMC and chemically crosslinked to the composite hydrogels by chemical crosslinker [7, 8] or irradiation [9, 10, 11]. Methylenebis acrylamide (MBA) always acts as a chemical crosslinker or a crosslinking enhancer agent in irradiation [12, 13, 14, 15]. Polyacrylic acid (PAA)/cellulose composite hydrogels have been widely reported for the applications of drug delivery and adsorbent. The negative carboxyl groups in PAA/CMC composite hydrogels facilitated the removal of cationic dyes via electrostatic interactions [16]. Cyclodextrin (CD) and CMC were grafting polymerized with AA to prepare CD/CMC-g-PAA hydrogels with pH sensitive as drug delivery system [17, 18]. A double crosslinking PAA hydrogel via visible-light-trigger polymerization, with CMC as initiator and the first crosslinker and MBA as the second crosslinker, showed a remarkably rapid recovery in both successive and intermittent cyclic tensile tests [19]. Hydrogels based on AM monomer and CMC were synthesized by gamma irradiation with MBA as a crosslinking enhancer agent for drug release system [20] and agrochemicals [21]. Interpenetrating double network was formed by chemically crosslinked polyacrylamide (PAM) network and physically crosslinked CMC network (Fig. 1). This shape memory hydrogels exhibited excellent tunable mechanical properties [22], which are similar to PAA/CMC composite hydrogels [19]. Both AM and AA were grafted onto CMC and further ionic coordinated to fabricate a tough hydrogel actuator with programmable folding deformation which showed great application prospect in soft machine. The ionic coordination was utilized to not only trigger the locally folding deformation of the hydrogels but also reinforce the mechanical property significantly [23]. By grafting poly(N-isopropylacrylamide) (PNIPAM) onto CMC, the self-association of grafted chains led to a thermothickening effect compared to the physical blends [24]. PNIPAM/CMC composite hydrogels with thermo- and pH responses are promising materials for protein and drug delivery [25, 26]. pH, thermo-, and redox ternary-responsive composite hydrogels were prepared by free-radical polymerization using methacrylated carboxymethyl cellulose (MACMC) and NIPAM as monomers [27]. PNIPAM and CMC were functionalized with hydrazide or aldehyde functional groups and mixed using a double-barreled syringe to create in situ gelling and hydrazone-crosslinked composite hydrogels, which provided a highly adaptable method of engineering injectable, rapidly gelling hydrogels for potential in vivo applications [28]. CMC can also be incorporated with some synthetic polymers to fabricate the composite hydrogels for medical and superabsorbent applications [29, 30].
Fig. 1

Scheme of PAM/CMC hydrogels with excellent shape memory effect. (Reproduced from [22])

MC is normally obtained by heating cellulose with a solution of sodium hydroxide and methyl chloride to replace the hydroxyl groups of cellulose by methoxyl groups. MC can form a thermoreversible physical hydrogel itself. At low temperatures, the hydrogen bonds formed and the polar water molecules form cages around the hydrophobic methoxyl groups of MC; upon heating, the hydrogen bonds and the water cages were broken to expose the hydrophobic side groups of MC chains, inducing hydrophobic associations and thus gelation [31]. MC-based injectable hydrogels for postoperation anti-adhesion were fabricated by mixing CMC, polyethylene glycol (PEG), and chitosan sulfate (CS-SO3) in the MC matrix with a low critical solution temperature (LCST) at 36 °C [32]. PAM/MC/montmorillonite (MMT) composite hydrogels were obtained through chemical polymerization of the AM monomer in aqueous solution containing MC and MMT which were appropriate for the controlled release of fertilizers with very high fertilizer loading in their structures [33]. PAM/MC semi-IPNs composite hydrogels were prepared by aqueous radical polymerization at room temperature, and MBA was used as a crossliking agent [34, 35]. Frontal polymerization (FP) was exploited as an alternative and convenient technique to prepare PAM/MC composite hydrogels swollen either in water or glycerol [36]. MC was modified with functional methacrylate groups and photocrosslinked to produce hydrogels for potential applications in plastic and reconstructive surgery [37]. Polythiophene-g-poly(dimethylaminoethyl methacrylate)-doped MC hydrogel behaved like a polymeric AND logic gate [38].

HPMC is produced by the addition of methyl and hydroxypropyl groups to the cellulose backbone. PAM/HPMC composite hydrogels were synthesized by radical polymerization technique which demonstrated controlled drug release behavior due to the hydrophobicity as well as lower rate of erosion [39, 40]. Thermosensitive PNIPAM/HPMC hydrogels were prepared, and swelling ratio of the hydrogel decreased with increasing temperature [41]. HPMC hydrogels containing PEG as crosslinks were prepared by reacting HPMC with polyethylene glycol dichloride which was a promising drug delivery system for the drugs to be delivered to the colon [42].

HEC is obtained by reacting cellulose with sodium hydroxide, and hydroxyl groups of cellulose are replaced by hydroxyethyl groups. Double-layered gels, consisting of HEC cryogel core and poly(ethylene oxide) (PEO) hydrogel shell, were synthesized with UV irradiation which were used as carriers for immobilization by entrapment of cells [43]. Composite hydrogels from poly(N-vinyl pyrrolidone) (PVP) and methyl hydroxyethyl cellulose (MHEC) were obtained via gamma irradiation [44]. PAA/HEC composite hydrogels were prepared by in situ method, and moduli of the composite hydrogels were improved dramatically compared to HEC [45]. HEC-g-PAA/vermiculite superabsorbent nanocomposites were prepared by radical solution polymerization among HEC, AA, and vermiculite in the presence of MBA as crosslinker [46]. PNIPAM/HEC composite hydrogels were prepared by copolymerization with NIPAM onto HEC, and LCST of hydrogels was enhanced by the introduction of HEC [47].

HPC is synthesized by chemical modification of cellulose with an etherifying agent, propylene oxide, which results in the introduction of hydroxypropyl side chains onto cellulose chains. Composite hydrogels with HPC and two methacrylate compounds were obtained by irradiation with γ-rays. Radiation-induced change of optical properties made them to be good candidates of a new type of radiation dosimeter utilized in radiation therapy [48]. Thermally sensitive hydrogels were prepared by crosslinking HPC with polyethylene glycol diglycidyl ether which swelled at low temperature and contracted at high temperature [49]. Ternary system thermoresponsive hydrogels, poly(N-isopropylacrylamide-co-hydroxyethyl methylacrylate polycaprolactone)/HPC (P(NIPAM-co-HEMAPCL)/HPC), were prepared via “alkynyl/azide” click chemistry between the azide-modified graft copolymer P(NIPAM-co-HEMAPCL-N3) and the alkynyl-modified HPC (Fig. 2). The composite hydrogels exhibited reversible swelling-deswelling behavior after three “swelling-deswelling” cycles [50]. Comb-shaped copolymer composed of HPC backbones and low-molecular-weight PNIPAM side chains were prepared via atom transfer radical polymerization (ATRP) for smart hydrogels in biomedical applications [51]. Methacrylic anhydride/HPC (MA/HPC) composite hydrogels for adipose tissue engineering applications were prepared and made to be biocompatible to human adipose-derived stem cells [52]. PAM/HPC composite hydrogels were prepared by in situ graft polymerization for heavy metal removal due to the capacity of both chemicals for forming chelates with metals [53]. PAA/HPC composite hydrogels were also fabricated via free-radical polymerization as absorbent, and a phase separation was revealed in the hydrogels [54].
Fig. 2

Preparation of the P(NIPAM-co-HEMAPCL)/HPC hydrogels via click chemistry [50]

2.2 Nanocellulose

Nanocellulose (NC) with high aspect ratio is partially to fully crystalline and exhibits impressive mechanical properties and tunable surface chemistries. Recently, the use of NC as a reinforcing agent for hydrogels has attracted significant research interest, especially in applications of tissue engineering scaffolds, wound healing materials, and drug delivery systems. There are three main reasons for the improved performance of the polymer hydrogels by incorporating NC, i.e., increased relative surface area (aspect ratios) and its associated quantum effects exhibited by NC, which formed polymer-filler interactions such as hydrogen bond, enhanced the elastic modulus with the rigid nanofibrils [55]. NC can be physically entrapped in the polymer network as a filler or chemically crosslinked with the polymer matrix in the composite hydrogels. Due to their rigidity and mechanical strength, NC acts as effective fillers in the composite hydrogels, and the majority of the NC composite hydrogel research has focused on the physical incorporation of NC as fillers. Common preparation methods include simple homogenization and physical entanglement of polymer networks, free-radical polymerization of polymeric species within NC suspensions, and UV/ion-mediated crosslinking of the polymeric network around the NC and cyclic freeze-thaw processing [56].

Incorporation of NC into synthetic polymer hydrogels can significantly improve the degradation and the mechanical strength of the hydrogels. The orientation of the reinforcing NC from the anisotropic to highly isotropic state under applied stress is the main mechanism of strain-dependent behavior of the composite hydrogels [57]. Polyvinyl alcohol (PVA) is among the most promising polymer candidates for the composite hydrogels because it is biocompatible, nontoxic, and readily crosslinked polymer. With the increase of NC concentration in PVA hydrogels, the composite hydrogels greatly improved the mechanical strength while maintaining remarkable ductility [58, 59]. PVA/NC composite hydrogels obtained by freezing-thawing (F-T) technique revealed increased thermal stability, mechanical properties [60], and proper water vapor transmission rate in the potential application of wound dressing [61]. The porous structure of PVA/NC hydrogels can be controlled by adding PEG with various molecular weights [62]. Hyperelastic, rubberlike PVA/NC composite hydrogels mimicking collagenous soft tissues are promising materials for ophthalmic applications [57, 63, 64]. The stiffness of PVA/NC composite hydrogels was significantly enhanced by utilizing three-component recognition-driven supramolecular crosslinks [65]. NC can also be chemically crosslinked with PVA to obtain the composite hydrogels [66, 67]. NC can be incorporated into PVA/chitosan [68] or PVA/alginate [69] to form the ternary composite hydrogels.

PNIPAM is a thermoresponsive polymer and has a LCST very close to the human physiological temperature. Incorporation of NC into PNIPAM hydrogels could obtain stimuli-responsive composite hydrogels which are promising in drug delivery. PNIPAM/NC composite hydrogels obtained by in situ radical polymerization of NIPAM monomer on the surface of modified NC (Fig. 3) could be elastically stretched to more than 700 times their original length [70] which attributed to the sustainer effect of the highly aligned NC fibers in the stretched hydrogels [71]. MBA was used to crosslink NC with PNIPAM by concurrent free-radical polymerization of monomers [72, 73, 74, 75]. Additionally, the negatively charged carboxylate groups on oxidized NC would favorably interact with hydrophilic amide groups in PNIPAM to form the network structure. AM, AA, and HEMA are common monomers to fabricate the PAM/NC [76, 77, 78, 79, 80, 81, 82, 83, 84, 85], PAA/NC [86, 87, 88, 89], and PHEMA/NC [90, 91, 92] composite hydrogels via in situ polymerization of monomers in the presence of NC.
Fig. 3

Surface modification of NC with MA and the following hydrogel formation via in situ polymerization of NIPAM [71]

3 Natural Macromolecules/Cellulose Composite Hydrogels

3.1 Polysaccharides

3.1.1 Chitosan

Chitosan is a linear copolymer obtained by deacetylation of chitin, and it is a polycation that has one amino group in the repeating glucosidic residue. The backbone of chitosan is very similar to cellulose excepted that some amino groups replace the hydroxyl groups on the C2 position. Chitosan is the most important polysaccharide which incorporated with cellulose to form the composite hydrogels with many applications. The chemical crosslinking is assuredly a highly versatile method to create chitosan/cellulose composite hydrogels with stable structure and effective swelling. According to the mechanism, crosslinking reactions between chitosan and cellulose can be classified into two types: (1) crosslinking with crosslinkers such as epichlorohydrin (ECH) and ethylene glycol diglycidyl ether (EGDE) and (2) crosslinking by the reactive groups in chitosan and cellulose or their derivatives. Chemical crosslinkers form covalent bonds and link chitosan with cellulose into network. ECH is a common etherifying crosslinker resulting in formation of ROR bonds. Etherification generally involves reactions in aqueous alkaline conditions (alkali catalysis) for the deprotonation of hydroxyl groups in order to make them highly nucleophilic and reactive with the crosslinker [93]. HEC and cationic modified chitosan can be crosslinked by ECH to prepare a double-network structure for loading anionic modified β-cyclodextrin (β-CD) via electrostatic interaction (Fig. 4). Incorporation of β-CD not only increased the mechanical strength of the composite hydrogels but also encapsulated hydrophobic guest substances by the host-guest interaction, and guest molecules could adsorb rapidly in the composite hydrogels and sustain the release in aqueous solution [94]. A water-soluble hydroxyethyl chitosan and cellulose were employed to fabricate the composite hydrogel scaffolds with bubble-like porous structure by a combination of chemical crosslinking with ECH, particle-leaching technique using silicon dioxide particles as porogen, and freeze-drying method. ECH mediated the chemical reactions between the hydroxyethyl or amino groups of chitosan and the hydroxyl groups of cellulose. The compressive modulus, equilibrium swelling ratio, and elasticity of the composite hydrogels were improved. In vitro biocompatibility evaluation demonstrated that the composite scaffolds could well support the attachment spreading, viability, and proliferation of cells [95]. EGDE with double epoxide groups was used to obtain the composite hydrogels with significant improved mechanical strength and chemical stability. The chitosan/cellulose composite hydrogel beads had high adsorption capacities for Cu removal which mainly involved the nitrogen atoms in chitosan to form surface complexes [96]. Thiourea-formaldehyde resin crosslinked chitosan and cellulose firstly, and AA was grafting polymerized on the composite hydrogels to obtain the superabsorbent in controlled release of soil nutrients [97]. Genipin, a biobased crosslinker, was used to crosslink amino groups of chitosan in the presence of CMC in order to form stable nanoparticles with semi-IPN structure, and magnetite was lastly synthesized within the composite particles by the coprecipitation method to obtain hybrid nanoparticles which exhibited the responsiveness to a magnetic field [98].
Fig. 4

The synthetic route of SEB-β-CD at hydrogel beads. (Reproduced from [94])

There are an abundance of amino groups in chitosan molecules, and they are feasible to react with aldehyde groups in oxidized cellulose derivatives to form a Schiff base which is an important chemical crosslinking to produce chitosan/cellulose composite hydrogels. Sodium periodate is a normal agent to cleave the C2-C3 bond of the anhydroglucose unit in cellulose and results in the formation of two aldehyde groups. Hydrogen peroxide was also used as an oxidant which oxidized CMC in the presence of sulfate copper, and the amount of aldehydes increased with the CuSO4 [99]. Due to the good water solubility, CMC was extensively employed to be oxidized to dialdehyde carboxymethylcellulose (DCMC) and self-crosslinked with chitosan or its derivatives based on Schiff base formation [100, 101, 102, 103]. The chitosan/DCMC composite hydrogels displayed significantly better thermostability, swelling capacity, and cytocompatibility compared with glutaraldehyde (GA) crosslinked carboxymethyl chitosan [100]. Chitosan/cellulose composite hydrogels with gelation driven by Schiff base reactions are highly porous materials which are capable of loading various potential therapeutic agents including cells, drugs, and growth factors, as drug delivery carriers of an anticancer drug, drug loading and releasing can be easily modulated by tuning the composition of the composite hydrogels. Protonation of carboxylic groups in the microsphere matrix at acidic conditions resulted in an accelerated release of doxorubicin, which is desired for treating tumors [101]. Chemical stability of the composite hydrogels was improved remarkably by grafting chitosan onto cellulose hydrogels prepared by dissolution-regeneration in LiOH/urea [104].

Irradiation is a useful method for the formation of covalent bonding between chitosan and cellulose to obtain the composite hydrogels. The advantages of this method are high purity of the hydrogel products without crosslinkers and tedious process to prepare polymer derivatives. High concentrated paste-like condition was favorable for irradiation crosslinking of chitosan or cellulose; meanwhile, degradation of the polymer chains competed with crosslinking during irradiation [105]. Carboxymethyl chitosan/CMC composite hydrogels were prepared by γ-irradiation of a high concentrated mixture solution revealing the high-adsorption capacities for metal ions. It was found that the maximum strength depended on the composition of the composite hydrogels. The behavior of the tensile strength of the composite hydrogels with increasing dose was similar to that of pure hydrogels [106, 107, 108]. Additionally, MBA as a radical crosslinker could be added to the mixed solution before irradiation to enhance the gelation efficiency [109]. It was reported that macroradicals emerged preferentially in weakened C1 and C4 positions of cellulose as a result of the fracture of C-H bonds upon irradiation, while macroradicals of the derivatives were created in the side chains during radical crosslinking [110, 111].

Chitosan/cellulose composite hydrogels can be fabricated by physical interactions as well such as hydrogen bonds, electronic or hydrophobic associations, chain entanglements, and van der Waals forces. Cellulose ethers such as MC, HEC, and HPMC are the most important water-soluble derivatives of cellulose which can form physical crosslinking composite hydrogels with chitosan via hydrophobic associations and hydrogen bonding. HPMC and MC are temperature-sensitive and will undergo abrupt change in solubility in response to increases in environmental temperature at LCST which is governed by the balance of hydrophilic and hydrophobic moieties on the polymer chains. At the LCST, phase separation occurred because the balance of hydrophilic and hydrophobic moieties on the polymer chain was broken which resulted in a more hydrophobic structure of the polymer. Thermoreversible chitosan/HPMC composite hydrogels were fabricated, and LCST was increased with the increment of chitosan proportion in the composite hydrogels. For HPMC gelation, hydrophobic associations among the macromolecules possessing the methoxy group are the main mechanism. As temperature increases, hydrated and simply entangled polymer chains gradually lose their water of hydration with hydrophobic associations and form the hydrogel network. By adding chitosan, the concentration of HPMC was decreased, and hydrogen bond between the OH groups of HPMC and NH2 groups of chitosan enhanced the interactions of two macromolecules. The ionization of the amino groups extended the distance between the chitosan molecules through cationic repulsion and favored the osmotic flow of the water into the network. Therefore, the hydrophilicity of the composite was enhanced resulting in the increased LCST [112]. The composite hydrogels displayed excellent thermal stability and good mechanical properties [113]. The composite hydrogels physically crosslinked by hydrogen bonding of carboxymethyl chitosan with HEC and MC were prepared for controlled drug release system. Better interaction is demonstrated in HEC composite hydrogels than that in MC composite hydrogels, owing to stronger intermolecular hydrogen bonding [114]. Polyol was also introduced into chitosan/HEC composite hydrogels to strengthen the hydrophobic interactions resulting in the incorporation of hydrophobic network into the hydrophilic network via IPN. The hydrophobic microenvironment can not only limit the swelling degree of the composite hydrogels but also act as reservoir of the drug [115]. The pH-responsive composite hydrogels slowed down the drug release rate by the moieties formed by hydrophobic network which was a promising approach to cover up the drawbacks of drug burst-release kinetics from the hydrogels [116]. The gelation temperature of CS-SO3/MC/CMC was around body temperature which made it a good candidate for injectable thermosensitive hydrogels for postoperation anti-adhesion [32]. Chitosan/cellulose composite hydrogels can also be fabricated through the different solubilities of the macromolecules in various solvents. Both cellulose and chitosan can be dissolved in ionic liquid and coagulated to composite hydrogels by adding certain antisolvents such as water and ethanol. By this method, the lipase could be entrapped into chitosan/cellulose composite hydrogels with higher immobilization yields than cellulose hydrogels [117]. Chitosan/cellulose composite hydrogels also exhibited good cell compatibility and non-cytotoxicity. Magnetic hybrid hydrogels were obtained by coating cellulose and chitosan in ionic liquid on the surface of Fe3O4 which revealed high adsorption capacities for different heavy metal ions [118].

The amino groups of chitosan can be ionized in acid conditions to make it positively charged and form the composite hydrogels with negative-charged cellulose derivatives such as CMC via electrostatic interaction. Chitosan/CMC composite hydrogels showed pH-responsive swelling behavior. In acidic solution, amino groups of chitosan were protonized to NH3+ groups which coagulated with COO to form the condensed network, whereas in alkaline solution, the amino groups were neutralized, and electrostatic linkages between the two functional groups disappeared which resulted in the swelling of the hydrogels by the electrostatic repulsion between carboxyl groups. In vitro evaluations of capsaicin from chitosan/CMC composite hydrogels showed the reduced flux of capsaicin compared to the single-component hydrogels [119]. Chitosan/CMC/carrageenan ternary composite hydrogels were prepared by ionic crosslinking between NH3+ of chitosan with COO of CMC and SO3 of carrageenan. Both pH and addition of salt influenced the degree of swelling by changing the crosslinking density and/or the homogeneity of the network. As shown in Fig. 5, the composite hydrogels have the phase-separated structure, which is changed by the electrostatic interaction among three kinds of polyelectrolytes. The homogeneity of the composite hydrogels strongly depended on the composition of carrageenan/CMC and the salt concentration. When the chitosan or salt concentration was low, highly crosslinked part appeared in a relatively low crosslinked network. Increasing the chitosan or salt concentration, the difference in the crosslinking density in the homogeneous composite hydrogels would be small [120]. Chitosan/CMC composite hydrogels with core-shell structure were obtained by ionic crosslinking CMC with the Zr tetravalent metal ions firstly and further complexing with chitosan for the potential applications in bone tissue engineering [121].
Fig. 5

Scheme representing heterogeneity of the chitosan/carrageenan/NaCMC composite hydrogels [120]

3.1.2 Alginate

Alginate, a water-soluble polysaccharide composed of D-mannuronic and L-guluronic acid residues, is an abundantly available biopolymer extensively used for hydrogels, and the ionotropic gelation of alginate can be achieved with several cations. Alkaline earth metals, transition metals, and certain post-transition metals are normally applied to form alginate hydrogels. Most of alginate/cellulose composite hydrogels were fabricated by utilization of the gelation of alginate with calcium ions, and cellulose was incorporated by dispersing in the composite hydrogels without taking part in forming the network. Water-soluble CMC is feasible to be mixed with alginate and crosslinked by Ca2+ to form alginate/cellulose composite hydrogels in order to remove some heavy metal ions such as Zn(II) [122], Chromium(VI) [123], and Hg(II) [124]. Both alginate and CMC are anionic in nature due to the presence of negatively charged carboxyl groups at pH > 5. These negative charges allow the polymers to shrink in the acidic pH and to swell when they are exposed to neutral or basic pH. Therefore, alginate/CMC composite hydrogels prepared by the ionic gelation are good candidates of the drug delivery [125]. The crosslinking rate for trivalent ions was faster than that of divalent ions due to their higher valency; the Al3+ crosslinked alginate/MC composite hydrogels improved not only the drug encapsulation efficiency but also drug release in alkaline media [126]. Addition of CMC to alginate gel significantly improved the yield of lactase immobilization and the activity of the fixed enzyme [127]. CMC and its grafted copolymer were also incorporated into the alginate hydrogels by ionic crosslinking at the presence of inorganics to form the ternary composite hydrogels [128, 129].

Recently, alginate/bacteria cellulose (BC) composite hydrogels are gaining more and more attentions as scaffolds for tissue engineering by combining beneficial properties of both BC and alginate. BC has advantages in terms of biocompatibility, nontoxicity, high mechanical strength, high swelling ability, and high stability to pH variations. Alginate can provide mechanical integrity in tissue engineering applications for its hydrogel properties. Several therapeutic agents, including antibiotics, enzymes, growth factors, and DNA, have already been successfully incorporated in alginate hydrogels in order to maintain high biological activity [130]. Normally, the BC pellicles were crushed to form BC slurry and mixed with the alginate solution, then crosslinked by Ca2+ to obtain the composite hydrogels for scaffold. The compression strength and chemical stability of the alginate/BC composites were increased compared with the alginate hydrogels [131]; cell proliferation and migration on the surface of the scaffolds were promoted as well [130, 132]. Silver sulfadiazine particles, topical antibacterial agents, were embedded into the alginate/BC composite hydrogels to render the enhanced antibacterial property for utility as potential wound dressings [133]. Multi-walled carbon nanotube was incorporated into alginate/BC composite hydrogels to get a pH and electric field dual-stimulus responsive drug delivery system [134]. Alginate/BC composite hydrogels were also good immobilization carriers of lipase [135] and yeast [136]. In application in lipase immobilization, a novel in situ method was employed. Alginate solution was mixed with G. xylinus suspension firstly, and the resulting mixture was then added into BaCl2 solution to gain the hydrogels. G. xylinus entrapped in the hydrogels successfully produced BC with a narrow distribution of fiber diameters. The prepared alginate/BC nanocomposite hydrogel beads showed consistent sizes and regular spherical shapes [135].

Alginate/cellulose composite hydrogels can be fabricated by ionic crosslinking by some trivalent cations with both macromolecules taking part in the formation of network. Trivalent cations such as Fe3+ and Al3+ can induce the gelation of alginate; meanwhile, CMC can produce hydrogels by coordinating with these trivalent cations [137] due to numerous carboxyls and hydroxyls in the molecular chains. The trivalent iron can be a more suitable crossliking agent for alginate/CMC composite hydrogels than divalent metal ions in drug delivery system due to the faster crossliking rate which can result in the higher load capacity and sustained release [128, 138]. Protein, drugs, and some bioactive compounds can be encapsulated into the composite hydrogels and controlled released from them. Albumin was embedded into the Fe3+-crosslinked alginate/CMC composite hydrogels, encapsulation efficiency was higher, and protein release was reduced in the gastric environment because of the pH sensitivity, which demonstrated that the alginate/CMC composite hydrogels presented a promising protein therapeutic carrier for the oral delivery [139]. The composite hydrogels also exhibited pH sensitive for delivering metformin hydrochloride (MH); the swelling degree and in vitro release profiles were higher by two orders at gastric conditions compared to an acidic environment [140]. Hesperidin-loaded efficiency in the alginate/CMC composite hydrogels was high, and in vitro release of hesperidin was prolonged. The composite hydrogels exhibited the ability to protect the encapsulated flavonoid glycoside during its passage through the simulated gastric environment, while under the simulated intestinal conditions, the transportation systems exhibited a pH-triggered release behavior [141]. The alginate/CMC composite hydrogels are also good absorbents to remove lead ions by physical, chemical, and electrostatic adsorptions [142].

Besides the ionic crosslinking, alginate and cellulose can be chemically crosslinked via some crosslinking agents to form the IPN composite hydrogels. There are numerous hydroxyl groups in both alginate and cellulose macromolecular chains; aldehyde groups of GA can form ether linkage with hydroxyl groups of alginate and cellulose as a result of the crosslinking reaction. Alginate/CMC composite hydrogels were prepared by crosslinking with GA and used for the delivery of carbaryl with higher entrapment efficiency. By increasing of exposure to GA or concentrations of GA, the crosslink density of the composite hydrogel matrix was changed to more compact network with increase in crosslink density resulting in reduced free volume and difficult diffusion of the carbaryl molecules [143]. AM was grafted onto HEC by free-radical polymerization and blended with sodium alginate to prepare pH-sensitive IPN composite hydrogels using GA as a crosslinking agent (Fig. 6). The covalent crosslinking leads to reduced swelling and introduces specific properties such as structural strength along with thermal and mechanical stability. In vitro release of diclofenac sodium was decreased with increasing GA content in the matrix due to the formation of a more tightly crosslinked rigid network structure [144]. ECH was also used as a crosslinker to react with the hydroxyl groups of cellulose and alginate chains through nucleophilic attack of the alcoholate anion, whereas a new epoxide formed by chloride displacement (Fig. 7). The combination of cellulose containing semi-stiff chain and alginate containing carboxyl groups created macroporous structure in the crosslinking hydrogels where cellulose contributed to support the pore wall and alginate acted as an expander of the pore size [145].
Fig. 6

Schematic representation of synthesis of IPN [144]

Fig. 7

Proposed mechanism for crosslinking reaction of cellulose and alginate with ECH [145]

3.1.3 Starch

Starch is an abundant renewable resource with low cost and broad-ranged capability in food and nonfood products. Starch granules have a semicrystalline structure, mostly composed of two different polysaccharides, amylose and amylopectin, with complicated internal structure. Starch/cellulose composite hydrogels can be prepared in chemical and physical crosslink of the network as well as with high-energy irradiation. Injectable adhesive hydrogels composed of starch and CMC were developed. Firstly, CMC was modified with tyramine to introduce crosslinking site, then the in situ hydrogel was prepared by an enzyme-mediated reaction of tyramine-immobilized CMC with horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). Starch was added to the hydrogel solution to be incorporated in the cellulose network as semi-IPN composite hydrogels. Starch can improve adhesiveness to the wound area and accelerate biodegradation of the hydrogels as injectable in situ anti-adhesive agents [146]. Starch/CMC/SiO2 composite hydrogels were fabricated using aluminum sulfate octadecahydrate as an ionic crosslinker which increased the water restoration capability of agricultural soil [147]. Starch-g-PAA/NC composite hydrogels were obtained by in situ copolymerization of AA onto starch and crosslink with MBA (Fig. 8). The large amounts of active -OH groups on the surface of NC can take part in the polymerization reaction as well as the construction of 3D polymer network [148, 149]. Composite hydrogels were prepared with cellulose from tea residue [150] or pineapple peel [151] in ionic liquid, followed by incorporating soluble starch by mixing the cellulose hydrogel with starch. Addition of soluble starch exhibited good cell compatibility and non-cytotoxicity to the composite hydrogels. The composite hydrogels from HPMC and starch demonstrated the typical behavior of “filled” composite systems having poor adhesion between the surface of the elastic starch “filler” and the continuous HPMC phase [152].
Fig. 8

Illustrative scheme for the structure of starch-g-poly(sodium acrylate)/CNWs composite hydrogels. Reproduced from [149]

High-energy irradiation technique is becoming an important approach in the crosslinking of polymers as it can efficiently replace the chemical crosslinking agents and produce hydrogels with high purity that do not need the removal of hazardous chemical crosslinkers. It allows the chemical crosslinking without the use of crosslinking agents which provides a convenient approach to crosslink polysaccharide at high concentrated aqueous solution mainly due to the mobility of side chains [153, 154, 155]. Side-chain radicals were formed mostly via indirect effects, by the abstraction of H atoms in the intermediate products of water radiolysis. Electron beam irradiation (EB) was used to prepare composite hydrogels from aqueous solutions of plasticized starch (PLST), cellulose acetate (CA), and CMC. A semi-IPN structure could be formed in which the network was mainly formed by crosslinked CMC and CA with PLST physically included [156]. Carboxymethyl sago pulp (CMSP)/carboxymethyl sago starch (CMSS) hydrogel was also synthesized by electron beam irradiation to produce the composite hydrogels with sustained release of drugs. The radicals on CMSP and CMSS chains can combine and form the intermolecular crosslinking between the molecular chains [157]. Gamma irradiation was also applied to prepare starch/CMC composite hydrogels as superabsorbent gels, in which the starch granules also participated in the crosslinking process resulting in the improved gelation. CMC chains reacted with the granule surface through the recombination of the radicals, and the reaction was not hindered by electrostatic repulsion during the crosslink formation between two CMC chains. The partial replacement of CMC with starch improved the gel fraction; however, very high starch content had a negative impact on the gelation [158].

3.1.4 β-CD

β-CD is a type of cyclic molecule composed of seven glucose units and derived from starch. β-CD possesses internal relatively hydrophobic cavity and exterior hydrophilic structure. These special structures make β-CD easy to form molecular complexes via interaction with other polymer network by virtue of intermolecular force. There are abundant hydroxyl groups in β-CD molecular; it is feasible to chemically crosslink β-CD and cellulose via some crosslinkers to obtain β-CD/cellulose composite hydrogels. Water-soluble CMC was crosslinked with β-CD via ECH, and the graft reaction involved usually nucleophilic substituent in cellulose. Meanwhile, β-CD of the heptatomic ring chain can attack the epoxy group of ECH and is then converted to a monoether of chloropropanediol [159]. Due to substitute and rearrangement of chloride, β-CD and CMC were linked together, and the network structure was constructed (Fig. 9). The prepared composite hydrogels were sensitive to changes of pH, temperature, and ionic strength [160]. NaOH/urea aqueous solution has been found to be a good solvent for cellulose; β-CD/cellulose composite hydrogels could also be synthesized in NaOH/urea aqueous solutions by crosslinking with ECH. Swelling degree of the composite hydrogels decreased with an increase of the β-CD content. The drug-loading capacity of the composite hydrogels was preferred to the hydrophobic drug due to the formation of complexation; however, only the molecules which can form a stronger inclusion complex with β-CD [161] can promote the release of the drug. The composite hydrogels-adsorbed aniline blue also caused enhanced fluorescence intensity with the potential application as a biological stain [162].
Fig. 9

Synthesis of the β-CD/cellulose composite hydrogels [159]

Citric acid (CA) has gained recognition as a nontoxic crosslinking agent for grafting β-CD onto cellulose, and anhydride formation of CA facilitated the ester crosslinks between cellulose and β-CD (Fig. 10). β-CD-grafted HPMC [163] and β-CD-grafted CMC [164] composite hydrogels were obtained with CA, and the controlled delivery of drugs with poor solubility of those composite hydrogels was investigated. The active β-CD content, carboxyl content, and swellability showed major contributions toward improvement of drug loading and retardance of drug release [163].
Fig. 10

Schematic representation of the formation of β-CD-CMC hydrogel film [164]

Hydroxypropyl-β-cyclodextrin (HPβCD) was crosslinked with HPMC via EGDE under mild conditions to prepare β-CD/cellulose composite hydrogels [165]. 1,4-butanediol diglycidyl ether (BDGE) was used as crosslinker to form β-CD/HPMC composite hydrogels which were conjugated with antimicrobial gallic acid to prevent wound infection [166]. β-CD and CMC were graft polymerized with AA, in the presence of MBA as a crosslinker to prepare β-CD/CMC-g-PAA composite hydrogels. The pH-sensitive composite hydrogels were conferred good mechanical properties with improved drug loading and release capability for the antiviral drug acyclovir [18].

β-CD can be incorporated into β-CD/cellulose composite hydrogels by noncovalent interactions as well. Hydrophobic cavities of β-CD can act as moieties capable of generating physical crosslinks, by making inclusion complexes with hydrophobically modified polymers or with amphiphilic polymers with hydrophobic chains, which combined to form host-guest complexes networks. β-CD can also be modified by some anionic or cationic groups to make it charged and form the composite hydrogels with opposite charged polymers via electrostatic interaction.

Cellulose can be dissolved in the mixed solvent of tetrabutylammonium hydroxide (TBAH) and Dimethyl sulfoxide (DMSO) because TBAH is capable to dissolve cellulose at the molecular level with effectively repulsive cellulose-cellulose interactions. Stiff composite hydrogels were formed when adding β-CD to the cellulose dopes because the formation of 1:1 β-CD:TBA+ host-guest complex [167] destabilized the cellulose solution state and triggered the composite hydrogels formation [168]. β-CD and ferrocene (Fc) were grafted onto cellulose individually to obtain β-CD-cellulose and Fc-cellulose; firstly, the composite hydrogels can be prepared by mixing two solutions by formation of inclusion complexes. The ferrocene forms of the inclusion complexes with β-CD effectively, whereas the oxidized ferrocene is basically impossible. Therefore, the host-guest interaction between the metal ferrocene with β-CD can also be a reversible regulation by oxidation and reduction of the ferrocene which resulted in the controlled sol-gel transition [169]. The hydrophobic lauryl side chains were grafted onto HEC firstly and mixed with water-soluble β-CD polymers. The cavities of β-CD polymers can provide hydrophobic binding sites with C12 side chains to obtain self-assembled composite hydrogels based on the host-guest interaction, and the residual cavities of composite hydrogels can load drugs (Fig. 11) [170]. β-CD-grafted NC was accomplished using ECH as a coupling agent and pluronic polymers were introduced on the surface of NC by means of inclusion interaction between β-CD and hydrophobic segment of the polymers to obtain supramolecular hydrogels [171].
Fig. 11

Scheme of the formation of self-assembled hydrogels and its drug-loading pattern [170]

Chitosan/HEC hydrogels were prepared by crosslinking firstly, the negative sulfonatedbutyl (SEB) β-CD (SEB-β-CD) was loaded into the hydrogels simply by immersing the hydrogels into the SEB-β-CD solution. The electrostatic interaction of cationic chitosan and anionic SEB-β-CD was the main driving force to immobilize the β-CD into the hydrogels. Moreover, the encaged SEB-β-CD can be controlled and released from the composite hydrogels with ion-exchange method by immersing it in electrolyte solution readily [94]. In addition, hydroxypropyl-β-CD (HP-β-CD) was immobilized into HEC [172], HPC [173], and HPMC [174] hydrogels at the same time of the crosslinking of cellulose derivatives.

3.2 Extracellular Matrix

The extracellular matrix (ECM) is the noncellular component presenting within all tissues and organs that not only provides essential physical scaffolding for the cellular constituents but also initiates crucial biochemical and biomechanical cues [175, 176]. The composite hydrogels-combined cellulose and ECM are very promising scaffolds for the tissue repair and regeneration, especially for the injectable self-healing hydrogels with the dynamic interactions. Collagen as a key ECM component for promoting cell cultivation is most widely used to fabricate the composite hydrogels, especially for bone reparation because of its weak antigenicity, excellent biocompatibility, and unique fibril-forming properties. Collagen is a kind of protein forming a characteristic triple helix of three polypeptide chains, and all members of the collagen family form these supramolecular structures in the extracellular matrix although their size, function, and tissue distribution vary considerably [177].

Dialdehyde cellulose is an attractive cellulose derivative because it can react with amino functional groups in collagen by the formation of Schiff base-type compounds [178, 179]. Regenerated cellulose hydrogel was obtained firstly and oxidized by periodate oxidation to obtain 2,3-dialdehyde cellulose (DARC) which presented a porous structure with tangled fibrils and interconnected networks. This unique structure was attributed to the phase separation of the cellulose solution during the regeneration process, where solvent-rich regions contributed to the formation of pores. Collagen was immobilized on cellulose via the Schiff base reaction between -NH2 in collagen and -CHO in DARC (Fig. 12). The self-crosslinked composite hydrogels showed great potential for use as a tissue engineering scaffold due to its high strength, malleability in situ, good equilibrium-swelling ratio, air permeability, and biocompatibility [180]. DCMC [181] with substantial degradation in periodate oxidization induced the crosslinking of collagen to macroporous structure [182].
Fig. 12

The schematic diagram of the preparation of DARC/Collagen (DACR/Col) composite film [180]

The cellulose hydrogels were prepared from cellulose solution dissolved in LiOH/urea aqueous system by crosslinking with ECH and then thermal crosslinked collagen by neutralizing the collagen solution to obtain collagen/cellulose composite hydrogels. The composite hydrogels integrated microfluidics with well-controlled pore size, good mechanical durability, cytocompatibility in cell culture, and excellent dimensional stability [183]. The amino groups in collagen provide Cu(II) binding sites through their chelating performance [184]. Collagen/cellulose hydrogel beads reconstituted from ionic liquid showed high Cu(II) adsorption capacity for removal of it from wastewater [185].

BC displays many unique properties including high water uptake capacity and an ultrafine nanofibril network structure which are essential for scaffolds in tissue engineering. To improve the biocompatibility and cell affinity of BC as wound dressing material, BC can be modified through the incorporation of collagen, and the collagen/BC composite hydrogels are very promising materials in skin tissue engineering. Collagen/BC composite hydrogels can be prepared by simply immersing wet BC pellicle into collagen solution followed by a freeze-drying process. The collagen molecules were not only coated on the BC fibrils surface but also penetrated inside BC, and hydrogen bond interactions were thus formed between BC and collagen [186]. According to the in vivo test and macroscopic evaluation, collagen/BC composite hydrogels showed better reparation ability of wounds and promoted statistically significant differences of tissue repair between treatments after surgery [187]. BC formed semi-penetrate hydrogels with alginate and immobilized collagen to ternary composite hydrogels which supported the growth of human skin fibroblast as deliver vehicles for therapeutic compounds during wound healing [188]. In order to improve thermal and mechanical properties of collagen/BC composite hydrogels, both GA and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride were used as crosslinkers to form the chemical bonds between collagen and BC [189].

3.3 Nanocellulose/Natural Macromolecules

NC can also be incorporated into natural macromolecules hydrogels such as chitosan, alginate, and gelatin which targeted biological or biomedical applications. GA was used as a crosslinker to chitosan because of its high reactivity toward the amine groups, and NC was incorporated into the network to improve mechanical properties and pH sensitivity of the chitosan/NC composite hydrogels [190, 191]. Carboxymethylated chitosan/NC aerogel for dye removal was prepared through Schiff base reaction. NC, bearing aldehyde and carboxylic acid groups, facilitated the crosslinking with chitosan through imine bond formation while providing negatively charged functional groups, and chitosan was modified to accommodate carboxylic acid [192]. Chitosan/NC sponge was prepared by lyophilization to be used as a new absorbable hemostat [193]. The carboxyl groups of NC and amino groups of chitosn were linked with peptide bonds forming stable hydrogel network [194]. Chitosan-g-PAA/NC composite hydrogels obtained by in situ polymerization showed responsive behavior in relation to pH and the salt solution [195]. Chitosan/NC/xanthan [196] and chitosan/BC/MMT [197] ternary composite hydrogels were also fabricated by lyophilization. Chitosan/BC composite hydrogels were prepared by co-dissolution of BC and chitosan in 1-Ethyl-3-methylimidazolium acetate ([Emim][Ac]) and reconstitution with water [198] or in situ method during biosynthesis which showed better effect on cell growth, cell proliferation, and biocompatibility [199].

For alginate/NC composite hydrogels, NC normally acts as reinforcement filler embedded in the alginate hydrogels crosslinked by metal ions. The alginate/NC composite hydrogels are effective absorbents to organic dyes [200], and the reusable composite hydrogels showed more than 97% dye removal efficiency after five successive adsorption-desorption cycles [201]. Alginate/BC hydrogel membrane was also used for separation of ethanol-water mixtures [202]. NC was firstly biofunctionalized by the covalent coupling of an enhanced avidin protein and used to fabricate 3D-printable bioactivated alginate/NC composite hydrogels [203]. IPN hydrogels based on NC in a matrix of alginate/gelatin were prepared via freeze drying and stabilized using CaCl2 and genipin which were potential in load-bearing biomedical applications such as cartilage replacement (Fig. 13) [204]. Double-membrane hydrogels from cationic NC and anionic alginate involved with an internal membrane consolidate by electrostatic interactions. The composite hydrogels with double-layer structures can realize the complexing drugs release with the first quick release of one drug and the successively slow release of another drug [205].
Fig. 13

Mechanisms of crosslinking reactions of (a) alginate/CaCl2, (b) alginate/NC, (c) genipin/gelatin, and (d) alginate/gelatin. (Reproduced from [204])

NC was employed to reinforce the cellulose and its derivative hydrogels such as CMC/HEC [206] and MC [207]. Injectable hydrogels based on CMC and dextran, reinforced with rigid rodlike NC as simple fillers and aldehyde-functionalized NC as chemical crosslinkers, were prepared with potential applications such as drug delivery vehicles or tissue engineering matrices [208]. Composite hydrogels based on CMC-g-P(AA-co-AM) and carboxylate NC were prepared by in situ graft polymerization in the presence of NC, and results showed that the composite hydrogels comprised a crosslinking structure of NC and CMC with side chains carrying AA and AM [209]. Gelatin [210, 211], collagen [212, 213, 214, 215], and starch [148, 149, 216] were also applied to fabricate the composite hydrogels with NC.

4 Inorganics/Cellulose Composite Hydrogels

4.1 Inorganic Minerals

Layered silicate, such as MMT, can form the microcomposite (Fig. 14a) and nanocomposite (Fig. 14b, c) hydrogels with polymers. The silicate can dispersed in the hydrogel matrix in nanoscale with two main structures: (1) intercalated (Fig. 14b), the polymer chains are inserted into the interlayer spacing of the stacking silicate platelets and (2) exfoliated (Fig. 14c), the individual layers are partitioned and dispersed in the polymer matrix. The exfoliated structure is more effective to improve the properties of the composite hydrogels for its greater phase homogeneity. Moreover, the polymer can act as a crosslinking agent by reacting with the groups on the surface of the inorganic plate. As shown in the Fig. 14d, the silicate platelets provide high surface area for multiple sites of crosslinking; meanwhile the polymer chains are flexible and can adopt random conformations for the long distances between the clay sheets which provide the cushion when the composite hydrogels are stretched or compressed. The performance of the clay composite hydrogels is largely influenced by the clay content and homogeneous dispersion in the matrix [217]. Compared to the monocomponent hydrogels, composite hydrogels have the combined properties of high mechanical strengths, elongations at break, and high rates of swelling/deswelling.
Fig. 14

Types of layered particle reinforced composites. (Reproduced from [217, 218])

Vinyl monomers such as AA and AM can be in situ polymerized and grafted onto the chains of cellulose derivatives in the presence of the layered silicate to prepare the composite hydrogels. The obtained superabsorbents revealed that the inorganic particles could be incorporated into the hydrogels matrix by reacting through the active groups on the surface. Silanol groups on the attapulgite (APT) [219] and hydroxyl groups on the MMT [220] make them facilitate to participate in the graft polymerization of CMC side chain of vinyl monomers. The remarkable pH sensitivity swelling behavior of the composite hydrogels was observed. Compared to the effects of cellulose derivates on swelling properties of the composite hydrogels, equilibrium water absorbency and the swelling rate in distilled water and saline solution are always in the order CMC > HPMC > MC > HEC. It was revealed that the influence of functional groups on swelling properties was great and the swelling properties of composite hydrogels were related to the hydrophilicity and the rigidity of functional groups [221]. Carboxyl group is an ion hydrophilic group which can be ionized; therefore, the polymeric network tends to swell, and the space for absorbing and holding water increases due to electrostatic repulsion. Moreover, the higher osmotic swelling pressure and chain relaxation process of CMC make it possess the higher swelling rate than other cellulose derivatives. Therefore, CMC is suitable to fabricate the inorganics/cellulose composite hydrogels for superabsorbent.

MMT is one of the most widely used layered silicates because its lamellar elements display high in-plane strength, stiffness, and high aspect ratio, which are beneficail to the properties of the composite hydrogels such as swelling ability, mechanical strength, and thermal stability. It has a 2:1 layer structure consisting of an octahedral alumina sheet sandwiched between two opposing tetrahedral silica sheets. The bonding between two silica sheets is very weak, which permits the water, exchangeable ions, and polymer chains to enter, and this leads to the development of nanocomposite hydrogels and their swelling capacity. The reactive hydroxyl groups and exchangeable cations on the surface of MMT can also make it act as a crosslinking agent between cellulose chains [220] and in situ intercalative polymerization [222, 223].

Cellulose-g-P(AA-co-AM-co-AMPS)/MMT composite hydrogels for superabsorbent were synthesized by using potassium persulfate as a free-radical initiator, in the presence of MBA as a crosslinking agent. The composite hydrogels comprised a crosslink structure of MMT and CMC with side chains that carried carboxylate, carboxamide, and sulfate [220]. CMC, MMT, and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) could be incorporated into AM hydrogels during free-radical solution polymerization; meanwhile the multifunctional crosslinker such as poly(ethylene glycol)diacrylate was used at the polymerization process to fabricate the highly swollen composite hydrogels [224]. Cellulose-g-PAA/MMT nanocomposite hydrogels were proved to be effective in controlled release of macro- and micronutrients; furthermore, a hydrolysis treatment improved their physicochemical properties. The presence of MMT not only remarkably enhanced their capacities of loading nutrient solutions but also acted as an effective barrier to control and retard the release of nutrients to the medium as well as played an important role in reducing production costs [225]. CMC-g-poly(NIPAM-co-AA)/MMT hydrogels were prepared by graft copolymerization of NIPAM and AA onto CMC in MMT/water suspension media, which were thermoresponsive and pH-sensitive hydrogels for removal of heavy metal ions from aqueous solutions [226]. MC was also used to prepare the nanocomposite hydrogels with PAM and MMT to slowly release of fertilizers [33]. Cellulose/MMT composite hydrogels were fabricated by chemical crosslinking cellulose and CMC with ECH in the presence of MMT nanosheets. MMT was first modified in order to make it take part in the formation of hydrogel network by reacting with cellulose. In this case, cellulose chains entered the galleries of MMT, and intercalated nanocomposite hydrogels were fabricated for highly efficient removal of dye in water [227].

Bentonite is a type of clay mainly composed of the crystalline structure of MMT and other additional crystalline structures. Composite hydrogels were synthesized by the graft copolymerization reaction among cellulose, polymethacrylic acid (PMAA), and bentonite; the inorganic bentonite particles in the network acted as additional network points. The PMAA-g-cellulose/bentonite could be effectively used as an adsorbent for the removal of dyes from water and wastewater [228]. CA-crosslinked CMC/bentonite composite hydrogels were prepared to develop base triggered release formulations of thiamethoxam due to their high swelling sensitivity under the basic pH condition, low cost, and environment-benign nature. Bentonite was added in the composite hydrogels to improve the barrier properties of formulations with enhanced rheological properties [229]. A new composite matrix for the controlled release of herbicides was prepared by adding bentonite or its acid-activated form into CMC gel [230].

Halloysite nanotubes (HNTs) with similar chemical formula as kaolinite possess unique empty lumen tubular morphology with outer diameters of 50 nm and inner lumens of 20 nm and 200–1000 nm long. They are biocompatible and widely available in nature, which make them good candidates for application in biomedicine by protecting the drug from enzyme degradation and delivery of the drugs to enter the cell. HNTs can be easily incorporated via solution mixing for cellulose composite hydrogels. HNTs were mixed into cellulose NaOH/urea solution to prepare composite hydrogels using ECH crosslinking at elevated temperature, and curcumin-loaded composite hydrogels showed a strong inhibition effect on the cancer cells and good cytocompatibility [231]. HNTs were firstly modified by the reaction of the external silanol groups with maleic anhydride and further reacted with adipic acid dihydrazide to introduce a hydrazine moiety on the clay surface. Functionalized HNTs were mixed with oxidized CMC to form biodegradable hydrazone bond to prepare the injectable composites hydrogels with potential applications in bone medication [232].

Similar to MMT, carclazyte is a layered aluminum silicate with exchangeable cations and reactive -OH groups on the surface. CMC-g-poly(AA-co-AM)/carclazyte composite hydrogels for superabsorbent were synthesized by graft polymerization of AA and AM onto CMC and the introduction of carclazyte. Additionally, ammonium persulfate (APS) and MBA were used as a free-radical initiator and a hydrophilic crosslinking agent, respectively [233]. Medicinal stone is a special igneous rock composed of silicic acid, alumina oxide, and more than 50 kinds of constant and trace elements. Vermiculite is a trioctahedral 2:1-layered silicate similar in texture to mica, and it is abundant and much cheaper in comparison with MMT [234]. Both medicinal stone and vermiculite can be incorporated with HEC-g-PAA to fabricate the composite hydrogels by the free-radical polymerization among HEC and AA which exhibited the enhanced swelling capability, swelling rate, excellent pH-responsive and good deswelling capability as potential water-manageable materials [46, 235].

4.2 Antimicrobial Nanoparticles

The synthesis of cellulose/nanoparticles hybrid composite hydrogels has attracted increasing attention especially for the nanoparticles (NPs) with special functions. Metallic NPs with inherent antimicrobial properties such as Ag, Zn, Au, and Cu are known to have broad-spectrum antimicrobial nature and pose minimum toxicity to humans. Particularly, nanosilver-based wound dressings have received approval for clinical applications, but dermal toxicity was reported [236]; therefore, the combination of hydrogels with silver NPs (AgNPs) is a better choice for the treatment of wounds [237]. There are free spaces within the cellulose hydrogels that could be utilized to incorporate NPs; meanwhile the incorporation of NPs into the hydrogel matrix reduces their agglomeration. Development of cellulose/NPs composite hydrogels is important to control growth of pathogenic microorganisms for the prevention of infectious diseases with good biocompatibility in the medical field. However, NPs have a tendency to aggregate to minimize their surface energy, which decreases their antimicrobial activity [238] and hinders the large-scale production with cost-effective dispersion methods. The methods of composite hydrogels preparation have a great influence on the structure and properties of the resulting composite hydrogels. For the preparation of cellulose/NP composite hydrogels, metals NP can be incorporated via two approaches: (1) ex situ, in which pre-synthesized NPs are incorporated into the cellulose hydrogel matrix and (2) in situ, in which cellulose matrix acts as a nano-reactor for synthesizing NPs. The antimicrobial NPs must be integrated in isolated and well-dispersed primary NPs inside the cellulose matrix to obtain the homogeneous composite hydrogels with good mechanical strength and enhanced antimicrobial activity.

4.2.1 AgNPs

AgNPs, efficient antimicrobial agents with little toxicity, are utilized in clothing, medical devices, cosmetic and pharmaceutical goods. AgNPs constitute an important component in nano-enabled consumer products available in the market. They are the most desirable antimicrobial NPs to be incorporated into the cellulose hydrogels. The antimicrobial property of AgNPs is governed by their size, shape, aggregation state, and so on. It is widely accepted that smaller the size of AgNPs is more beneficial to the antimicrobial activity due to higher penetration rates. Although the truncated AgNPs appear to be higher antimicrobial efficiency than spherical AgNPs, spherical AgNPs are usually preferred over other shapes due to their ease in synthesis, controlling on particle size, handling, and recovery for use. Hydrogels can afford free spaces between the networks in the swollen stage that serve for nucleation and growth of NPs and act as nanoreactors or nanopots. The crosslink densities were proved to be important in controlling the size and shape of the AgNPs within the hydrogel networks which was a facile synthetic strategy for tuning AgNPs to the desirable morphology (Fig. 15) [239].
Fig. 15

Hydrogel networks used as templates to synthesize of silver NPs [239]

CMC [240, 241] and hydroxypropyl CMC [242] can be used as reducing and stabilizing agents for green preparation of AgNPs, the hydroxyl groups form coordination bonds with silver ions, and carboxylic groups have electrostatic interaction with Ag ions which facilitate the reduction of Ag ions by CMC. A two-step process was the most common mechanism for synthesis of AgNPs, i.e., single-atom formation and then polymerization of the atoms to a particle. Firstly, a portion of metal ions in a solution is reduced by the available reducing groups of the cellulose and its derivatives; the produced atoms act as nucleation centers and catalyze the reduction of the other metal ions remaining in the bulk of solution. Subsequently, these formed atoms coalesce together to form metal clusters, and the ions attracted to the surfaces of these clusters are reduced further to aggregate to NPs. The formed particles are stabilized by a layer from the polymer matrix, thus preventing further coalescence of these NPs to larger particles [242, 243]. Synthesis procedures using microwave irradiation were also employed to accelerate the process. Microwave radiation of CMC and silver nitrates solution produced uniform AgNPs that were stable for 2 months at room temperature [244].

In situ: Cellulose and its derivatives can be chemically crosslinked into hydrogels, and AgNPs can further be incorporated into hydrogels matrix by in situ synthesis. CMC was converted to hydrogels using ECH as a cross linking agent. Two strategies were employed to obtain the CMC/AgNPs composite hydrogels: the first involved reaction of ECH with CMC in alkaline medium containing silver nitrate to synthesize AgNPs and form CMC networks simultaneously; the second entailed previous preparation of CMC hydrogel and reduction Ag+ ions into AgNPs within the swollen hydrogels. Both of CMC/AgNPs composite hydrogels showed uniform distribution of NPs in the hydrogels matrix, and the composite hydrogels obtained by the first strategy exhibited high antibacterial activity against Gram-positive and Gram-negative bacteria [237]. Fumaric acid was also used as a crosslinker to prepare the CMC/AgNPs composite hydrogels with the first strategy to render cotton fabrics for antibacterial property with the potential applications in wound dressings [245]. With the second strategy, hydrogels with CMC, PVA, and the crosslinker EGDE were fabricated, and AgNPs were incorporated by using trisodium citrate as a reducing agent under microwave radiation. The hydrogel matrix mainly provides steric protection to the Ag+ due to the polymeric network by direct bonding with these electron donor sites. The obtained composites hydrogels exhibited high antibacterial activity against urinary tract infection (UTI) pathogens [246]. CMC-poly(diallyldimethylammonium chloride) (DADMAC) hydrogels were fabricated by graft copolymerization of DADMAC onto CMC using APS as a free-radical initiator and MBA as a crosslinker. AgNPs or CuO NPs were incorporated into the hydrogels by immersing the CMC-poly(DADMAC) hydrogels into AgNO3 solution or copper sulfate solution and reducing or oxidizing to NPs in situ. The prepared composite hydrogels can be used in different medical fields, i.e., drug delivery and wound dressing as well as wound healing [247]. Semi-IPN hydrogels based on crosslinked PAM through an optimized rapid redox solution polymerization with MBA in presence of CMC were synthesized, and silver ions were in situ reduced using Azadirachta indica (Neem) plant extract under atmospheric conditions. The obtained pH-responsive composite hydrogels were suitable to safely transfer the drug through the stomach with acidic pH and release it successfully in the basic environment of the colon [248]. AgNPs can be transformed into Ag3PO4 NPs by the reaction of Ag and HPO42− to prepare Ag3PO4/cellulose composite hydrogels [249].

Layered double hydroxides (LDHs) which consist of brucite-like sheets containing both bivalent and trivalent cations were employed to prepare physically crosslinked CMC composite hydrogels by intercalating CMC into different LDHs. AgNPs/CMC-LDH composite hydrogels were prepared through in situ formation of AgNPs within the CMC-LDHs hydrogels. Figure 16a illustrated the formation of CMC-LDH hydrogels through co-precipitation by dropping solution of mixed M2+/Al3+ metal ions into alkali-CMC solution in order to precipitate LDH layers and intercalate CMC chains into LDHs. The electrostatic interaction between negative CMC and positive LDH sheets made LDHs act as inorganic crosslinkers in the composite hydrogels. Figure 16b represented the immobilization of AgNPs in the CMC-LDH hydrogels by in situ synthesis of AgNPs by the utilization of CMC as reducing and stabilizing agents. The silver ions are exchanged to the CMC-LDH networks firstly by anchoring through -COONa and -OH groups in CMC chains and then followed by reduction with the existing hydroxyl groups in CMC [31, 32, 33]. The LDH surface not only acts as a substrate to anchor and grow AgNPs but also is important in the stabilization of NPs through interactions between NPs and hydroxyl groups of the LDH surface [250]. AgNPs were well distributed within the AgNPs/CMC-LDHs composite hydrogels, and the hydrogels revealed a pH-dependent swelling behavior and good antibacterial activity to both Gram-negative and Gram-positive bacteria [251].
Fig. 16

The schematic representation of the formation of CMC-LDH hydrogels (a) and AgNPs/CMC-LDH composite hydrogels (b). (Reproduced from [251])

NC can also form the composite hydrogels with AgNPs by in situ reduction of Ag ions [252, 253]. The negatively charged surface carboxylate groups of TEMPO-oxidized NC provide high binding capability to Ag ions which triggers rapid gelation of the NC because transition metals are capable of resulting in carboxylate metal ion complex formation. Simultaneously, Ag+ was reduced slowly into AgNPs with prevalent hydroxyl groups on NC without additional reducing agents [252]. BC fibers are assembled by bundles of thinner cellulosic fibers with diameter sizes down to micro- and nanoscale. An extended network is observed via both intramolecular and intermolecular hydrogen bonds [254] enabling the production of sheets with high surface area and porosity. BC network has a very high affinity for water which results in hydrogel-like properties; therefore, BC hydrogel can embed the NPs to fabricate the composite hydrogels. GO-AgNPs/BC hydrogel microfibers were prepared with the microfluidic technology which exhibited a well-defined coaxial cable-like structure, with GO-AgNPs in the inner-core layer and BC hydrogel in the outer-shell layer. GO-AgNPs/BC hydrogel microfibers revealed efficient activity to sterilize both Gram-positive and Gram-negative bacterial strains with low cytotoxicity [255]. AgNPs/BC composite hydrogels could be obtained by UV light irradiation in situ with AgNPs photochemically deposited onto the BC gel network as well as chemically bonded to the cellulose fiber surfaces [256].

Ex situ: The super-macroporous polymer hydrogels based on HPC and PAM were obtained by UV irradiation of moderately frozen systems, using hydrogen peroxide as a source of radicals. H2O2 generated hydroxyl radicals during its photo-homolysis which reacted with the polymer molecules giving rise to macroradicals. The crosslinking occurred by intermolecular recombination of two macroradicals. AgNPs were immobilized in the channels of the gel by immersing a freeze-dried HPC cryogel in aqueous dispersion of AgNPs or incorporated into the polymer matrix by mixing of the AgNPs dispersion and HPC followed by freezing and subsequent crosslinking. The two types of composite hydrogels exhibited completely different releasing process of AgNPs; the gels containing AgNPs only in the channels could release them immediately by compression, while the gels with AgNPs embedded in the walls exhibited a slow release of Ag for months because AgNPs were physically entrapped within the dense polymer network. Thus, composite hydrogels with different release profiles could be obtained by different ex situ incorporation methods which were beneficial to controllable release of AgNPs [257]. Cellulose-based sponges were developed by freeze drying of regenerated cellulose gels and incorporated the prepared AgNPs by immersing the sponges into the AgNPs suspension. The composite sponges showed excellent antibacterial activity with prolonged release of AgNPs, high sorption of simulated wound fluids, and high water vapor transmission ability due to hydrophylicity of cellulose and porous structure, resulting in the cellulose-based sponges as promising wound dressing materials for fester and infected wounds [258]. AgNPs can also be coated with PEG, sodium dodecyl sulfate, and β-CD before loading into the cellulose hydrogels in order to improve the stability of the NPs and reduce the growth of the particles via trapping of seeds and steric repulsion [259].

4.2.2 ZnO NPs

ZnO NPs possess antibacterial activity to both Gram-positive and Gram-negative bacteria which may be related to the induction of oxidative stress due to generation of reactive oxygen species and the degradation of the membrane structure of the cell. They even have antibacterial activity against spores that are high-temperature-resistant and high-pressure-resistant [260]. Due to the lower cost, lack of color, and UV-blocking properties of ZnO NPs, they are used as alternatives to AgNPs to incorporate with cellulose hydrogels [261, 262]. Like AgNPs, ZnO NPs can be embedded into the cellulose hydrogels by in situ formation or ex situ process.

In situ: CMC hydrogels were prepared by crosslinking with ECH firstly, and ZnO NPs were formed in situ oxidation of the Zn2+ ions within swollen CMC hydrogels. Figure 17 represents in situ formation of ZnO NPs in CMC hydrogel network. Carboxylate groups in CMC easily bind to the Zn2+ cations in aqueous solutions via electrostatic interactions, and the zinc ions are oxidized to ZnO NPs with the basic agent. ZnO NPs with size range of 30–40 nm were well dispersed in the hydrogels matrix at low zinc nitrate concentration, whereas some aggregation and bigger particle sizes (50–65 nm) could be seen for the CMC/ZnO composite hydrogels at higher concentration. This procedure is facile and economically not requiring heat or any other tools for NP synthesis. The prepared composite hydrogels showed pH- and salt-sensitive swelling behaviors with excellent antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria [263]. The multifunctional carboxylic acids such as malic, succinic, and CA were used to crosslink CMC into hydrogels via esterification reaction between the OH group and COOH groups, and dehydration between the COOH groups and adjacent CMC molecules to give rise to strong hydrogen bonding during the thermal treatment [264].
Fig. 17

The schematic representation of in situ formation of ZnO NPs in CMC hydrogel network [263]

CMC can form complexes with Zn2+ due to its large number of coordinating functional groups in its molecular chains, and the precipitations of nuclei start as the concentrations of Zn2+ and OH ions exceed the critical values. The precipitated Zn(OH)2 can be transformed into the ZnO crystals via the simple chemical reaction by heat [265]. ZnO NPs/cellulose composite hydrogel particles were fabricated by using ZnCl2 aqueous solution as both the solvent of cellulose and the zinc source of ZnO nanoflakes. ZnCl2 aqueous solution can effectively dissolve cellulose, and reactive hydroxyl groups in the cellulose chains can accelerate the formation of ZnO nano-structures by reacting with Zn2+ to form Zn(OH)42−/cellulose complex through co-gelation process and transforming to ZnO nanocrystals at low temperature. ZnO nanoflakes are hexagonal structured nanoflakes with lamellar thickness of about 100 nm. Cellulose dissolved in ZnCl2 contributed not only to the growth of ZnO nanoflakes but also to restrain the formation of impurity phase [266]. Cellulose solution dissolved in NaOH/urea revealed that the sol-gel transition and intra- and intermolecular hydrogen bonds of cellulose tended to be increased as a result of its strong self-association tendency to cause aggregation and chain entanglements for the gelation [267]. ZnO NPs were grown in the network of cellulose hydrogels in situ to form the composite hydrogels [268]. Like AgNPs, ZnO was also incorporated into BC hydrogel-like pellicle by in situ synthesis of ZnO via solution plasma process without the addition of a reducing agent [269].

Ex situ: CMC was dissolved in distilled water and mixed with ZnO NPs to a homogenous solution; Fe3+ ion as a physical crosslinking agent was used to prepare ionic crosslinked CMC/ZnO NPs composite hydrogels by combination of metal coordination and ion exchange interaction between the carboxyl groups of CMC chains and Fe3+ cations. The pH-sensitive composite hydrogels showed high drug incorporation efficiency and a sustained release pattern. The release time of drugs from CMC/ZnO beads was prolonged because of a longer path to migrate from hydrogels containing ZnO NPs to the buffer solution, shown in Fig. 18. The prepared CMC/ZnO NPs composite hydrogel beads might function as oral drug delivery systems for the controlled delivery of drugs [270]. In order to control the stability of the ZnO NPs, it was loaded on mesoporous MCM-41 through impregnation. ZnO-impregnated MCM-41 was added into CMC solution and further crosslinked with CA to obtain the composite hydrogels. ZnO-MCM-41 highly increased the drug loading, and addition of ZnO-MCM-41 into CMC hydrogels caused a prolonged and continued release of drugs [271]. Both ZnO and ZnO2 NPs were loaded into the cellulose-chitosan hydrogels by dispersing the NPs into the polymer solutions before crosslinking. Cellulose and chitosan were crosslinked with triethyl orthoformate, which the primary amino group in chitosan and hydroxyl group in cellulose reacted with ethylformate, respectively. The composite hydrogels are potential new materials for tissue engineering applications with enhanced angiogenesis with zinc NPs, and it was proved that ZnO2-loaded hydrogels supported angiogenesis better than the ZnO-loaded hydrogels because of the difference in oxidation potential [272].
Fig. 18

The drug release of pristine CMC hydrogel and CMC/ZnO composite hydrogel [270]

4.3 Carbon Nanomaterials

Graphene and its derivates such as graphene oxide (GO) have been targeted on mechanically or electrically enhanced cellulose hydrogels as nanofillers. Specifically, GO shows the strong functionalities and processibilities due to the oxygen-containing functional groups on its basal planes and edges. The layered structure with oxygen-containing groups, i.e., hydroxyl, epoxide, and carboxyl groups, makes GO to be a favorable candidate for improving the mechanical strength of the cellulose hydrogels.

Normally, GO dispersion can be mixed with the cellulose solutions firstly and fabricated the GO/cellulose composite hydrogels further by crosslinking of cellulose. GO was mixed into cellulose dissolved in NaOH/PEG, and then the composite hydrogels were regenerated with the introduction of hydrochloric acid which neutralized NaOH and caused the reconnect and entanglement of cellulose chains by hydrogen bonds [273]. Both GO and cellulose dissolved in ionic liquids were mixed and regenerated using water as a coagulant to composite hydrogels which significantly enhanced mechanical strength and thermal stability [274]. CMC could be chemically crosslinked with CA in the presence of GO to obtain the GO/CMC composite hydrogels, and the introduction of GO also significantly improved the adsorption performances of the composite hydrogels toward dyes and heavy metals [275]. GO/CMC-g-PAA and GO/CMC-g-PAM composite hydrogels were fabricated by in situ copolymerization of monomers on CMC backbone with MBA as a crosslinker in the presence of GO as fillers [276, 277]. GO/CMC composite hydrogels via electron beam radiation-assisted polymerization with MBA as a crosslinking agent showed larger gel fraction, higher mechanical strength and swelling capabilities compared to those prepared by solution polymerization with ECH as a crosslinker [278]. Moreover, GO and the dissolved cellulose in the NaOH/urea were crosslinked with ECH; the incorporation of GO chemically increased the compressive strength of the composite hydrogels and significantly improved their adsorption capacities for the metal ions [279].

GO/CMC composite hydrogels physically crosslinked with Fe3+ and Ca2+ ions were prepared via the coordination between metal ions and the carboxyl groups in the CMC side chains. Due to the biocompatibility and the anionic-exchange properties of GO, the composite hydrogels revealed higher loading capacity and controlled release of the drugs [280, 281]. GO/CMC/PAM composite hydrogels with double networks consisting of ionically (Al3+) crosslinked CMC and covalently crosslinked PAM exhibited superior mechanical properties by combination of double networks and nanofiller reinforcement [282]. In order to decrease aggregation of GO, HPC was grafted onto GO before fabricating the composite hydrogels [283].

The recent emergence of three-dimensional (3D) graphene hydrogels has provided a promising avenue to explore the performance of 3D porous material on electrochemistry [284, 285]. GO/cellulose composite hydrogels could be fabricated by ball milling of the mixture of GO hydrogels and cellulose solution in the presence of hydrazine, template shaping, coagulating, and freeze drying. The hydrogen bond interactions and the shearing force collaboratively resulted in sufficient mixing of GO and cellulose and the subsequent formation of homogenous GO/cellulose hydrogels. It is a scalable preparation method of GO/cellulose composite hydrogels with application in supercapacitors.

GO could be incorporated into BC hydrogels with ex situ composites synthesis [286, 287, 288]; however intrinsically 3D structure of BC was broken [289]. In situ BC composites synthesis is becoming a main approach in which reinforcement materials are added to BC culture media at the beginning of the BC synthetic process. Microfibrils of BC become denser with time and produce a network structure that can trap various materials added to the BC synthetic media. The encaged materials become part of the BC fibril network, resulting in BC composites. GO/BC composite hydrogels were prepared by in situ biosynthesis of BC in graphene-dispersed culture medium. The addition of graphene reduced the crystallinity of BC without changing the entangled network structure [289, 290]. GO/BC composite hydrogels followed a non-Fickian diffusion mechanism in the drug release with good cell viability for drug delivery system [291].

Carbon nanotubes (CNTs) demonstrate very interesting properties because of sp2 hybridization of carbon-carbon bonds and the resultant cylindrical arrangement of the graphene sheets. In the realm of drug delivery, CNTs have gained tremendous attentions as promising nanocarriers, owing to their distinct characteristics, such as high surface area, enhanced cellular uptake, and the possibility to be easily conjugated with therapeutics, including both small molecules and biologics, displaying superior efficacy, enhanced specificity, and diminished side effects [292]. Carbon nanodots (C-dots) as new carbon nanomaterials have obtained increasing attentions for the applications of bioimaging, sensing, and catalysis fields, due to their exceptional properties such as highly fluorescent feature, low toxicity, excellent dispersibility in water, flexible functionalization, and good biocompatibility. C-dots possess numerous oxygen-containing functional groups on their surfaces such as hydroxyl groups, carboxyl groups, and epoxide groups, which indicate that C-dots have the promising potential application as physical crosslinkers in the preparation of NC hydrogels [293].

CNT/CMC composite hydrogels were fabricated simply by mixing CMC and CNTs at room temperature by ultrasonication; the strong hydrogen bonding as well as electrostatic interactions between acid groups of CNT and hydroxyl/carboxyl groups of CMC were believed to be the main reasons to form the composite hydrogels [294]. High-strength composite hydrogels were designed and synthesized by introducing CNTs into cellulose/NaOH/urea aqueous solution and chemically crosslinked by ECH [295]. Cellulose nanofibrils and BC were also used to fabricate the CNT/cellulose composite hydrogels [296, 297, 298, 299, 300].

5 Conclusions

Three categories of cellulose-based composite hydrogels were summarized in this chapter including synthetic polymer/cellulose, natural macromolecules/cellulose, and inorganics/cellulose composite hydrogels. The composite hydrogels combine the advantages of two components and obtain the new features for broadening applications especially in biomedical and tissue engineering, drug delivery, biosensors, and superabsorbent. It is feasible to incorporate some synthetic polymers with water-soluble cellulose derivatives to fabricate the synthetic polymer/cellulose composite hydrogels by chemical, physical, and ionic crosslinking. In situ free-radical polymerization of acrylate monomers onto cellulose derivatives is one of main methods to introduce synthetic polymers into cellulose-based hydrogels. Nanocellulose with high-aspect ratio can be physically entrapped in the polymer network as a filler or chemically crosslinked with the polymer matrix in order to improve the degradation and the mechanical strength of the composite hydrogels. Chitosan, alginate, starch, and extracellular matrix are popular natural macromolecules for the fabrication of natural macromolecules/cellulose composite hydrogels. Chitosan is the most important polysaccharide to form the composite hydrogels with cellulose by chemical crosslinking. Chitosan can crosslink with cellulose via crosslinkers such as epichlorohydrin or reaction between reactive groups in chitosan and cellulose derivatives. Inorganics/cellulose composite hydrogels are a kind of special hydrogels combining both inorganic and organic properties. Montmorillonite and other layered silicates can form the nanocomposite hydrogels with cellulose for applications of superabsorbent and controlled release of nutrients. Metallic nanoparticles with inherent antimicrobial properties such as Ag were also incorporated into the cellulose composite hydrogels via ex situ and in situ methods to render antimicrobial. Carbon nanomaterials such as graphene oxide can be incorporated into the cellulose hydrogels as fillers, and the composite hydrogels show potential applications in supercapacitors and biosensors. Cellulose-based composite hydrogels are attracting considerable attentions in both academic research and industrial application due to their excellent hybrid properties.


  1. 1.
    Silva AK, Richard C, Bessodes M, Scherman D, Merten OW (2009) Growth factor delivery approaches in hydrogels. Biomacromolecules 10(1):9–18PubMedCrossRefGoogle Scholar
  2. 2.
    Chang CY, Zhang LN (2011) Cellulose-based hydrogels: present status and application prospects. Carbohydr Polym 84(1):40–53CrossRefGoogle Scholar
  3. 3.
    Fekete T, Borsa J, Takács E, Wojnárovits L (2016) Synthesis of cellulose-based superabsorbent hydrogels by high-energy irradiation in the presence of crosslinking agent. Radiat Phys Chem 118:114–119CrossRefGoogle Scholar
  4. 4.
    Wang WB, Wang AQ (2010) Nanocomposite of carboxymethyl cellulose and attapulgite as a novel ph-sensitive superabsorbent: synthesis, characterization and properties. Carbohydr Polym 82(1):83–91CrossRefGoogle Scholar
  5. 5.
    Gao XY, Cao Y, Song XF, Zhang Z, Zhuang XL, He CL, Chen XS (2014) Biodegradable, ph-responsive carboxymethyl cellulose/poly(acrylic acid) hydrogels for oral insulin delivery. Macromol Biosci 14(4):565–575PubMedCrossRefGoogle Scholar
  6. 6.
    Bajpai AK, Mishra A (2004) Ionizable interpenetrating polymer networks of carboxymethyl cellulose and polyacrylic acid: evaluation of water uptake. J Appl Polym Sci 93(5):2054–2065CrossRefGoogle Scholar
  7. 7.
    Wang WB, Wang AQ (2011) Preparation, swelling, and stimuli-responsive characteristics of superabsorbent nanocomposites based on carboxymethyl cellulose and rectorite. Polym Adv Technol 22(12):1602–1611CrossRefGoogle Scholar
  8. 8.
    Mohy Eldin MS, El-Sherif HM, Soliman EA, Elzatahry AA, Omer AM (2011) Polyacrylamide-grafted carboxymethyl cellulose: smart pH-sensitive hydrogel for protein concentration. J Appl Polym Sci 122:469–479CrossRefGoogle Scholar
  9. 9.
    Said HM, Abd Alla SGA, El-Naggar AWM (2004) Synthesis and characterization of novel gels based on carboxymethyl cellulose/acrylic acid prepared by electron beam irradiation. React Funct Polym 61(3):397–404CrossRefGoogle Scholar
  10. 10.
    Abd El-Mohdy HL (2015) Radiation initiated synthesis of 2-acrylamidoglycolic acid grafted carboxymethyl cellulose as pH-sensitive hydrogel. Polym Eng Sci 54(12):2753–2761CrossRefGoogle Scholar
  11. 11.
    Abdel Ghaffar AM, El-Arnaouty MB, Abdel Baky AA, Shama SA (2016) Radiation-induced grafting of acrylamide and methacrylic acid individually onto carboxymethyl cellulose for removal of hazardous water pollutants. Des Monomers Polym 19(8):706–718CrossRefGoogle Scholar
  12. 12.
    Vimala K, Samba Sivudu K, Murali Mohan Y, Sreedhar B, Mohana RK (2009) Controlled silver nanoparticles synthesis in semi-hydrogel networks of poly(acrylamide) and carbohydrates: a rational methodology for antibacterial application. Carbohydr Polym 75(3):463–471CrossRefGoogle Scholar
  13. 13.
    Fekete T, Borsa J, Takács E, Wojnárovits L (2016) Synthesis of carboxymethylcellulose/ acrylic acid hydrogels with superabsorbent properties by radiation-initiated crosslinking. Radiat Phys Chem 124:135–139CrossRefGoogle Scholar
  14. 14.
    Wang WB, Wang Q, Wang AQ (2011) pH-responsive carboxymethylcellulose-g-poly (sodium acrylate)/polyvinylpyrrolidone semi-IPN hydrogels with enhanced responsive and swelling properties. Macromol Res 19(1):57–65CrossRefGoogle Scholar
  15. 15.
    Salama A (2015) Carboxymethyl cellulose-g-poly(acrylic acid)/calcium phosphate as a multifunctional hydrogel composite. Mater Lett 157:243–247CrossRefGoogle Scholar
  16. 16.
    Mandal B, Ray SK (2016) Removal of safranine t and brilliant cresyl blue dyes from water by carboxy methyl cellulose incorporated acrylic hydrogels: isotherms, kinetics and thermodynamic study. J Taiwan Inst Chem Eng 60:313–327CrossRefGoogle Scholar
  17. 17.
    Maswal M, Chat OA, Dar AA (2015) Rheological characterization of multi-component hydrogel based on carboxymethyl cellulose: insight into its encapsulation capacity and release kinetics towards ibuprofen. Colloid Polym Sci 293(6):1723–1735CrossRefGoogle Scholar
  18. 18.
    Malik NS, Ahmad M, Minhas MU (2017) Cross-linked beta-cyclodextrin and carboxymethyl cellulose hydrogels for controlled drug delivery of acyclovir. PLoS One 12(2):e0172727. Scholar
  19. 19.
    Zhu LX, Qiu JH, Sakai E, Ito K (2017) Rapid recovery double cross-linking hydrogel with stable mechanical properties and high resilience triggered by visible light. ACS Appl Mater Interfaces 9(15):13593–13601PubMedCrossRefGoogle Scholar
  20. 20.
    El-Din HMN, Alla SGA, El-Naggar AWM (2010) Swelling and drug release properties of acrylamide/carboxymethyl cellulose networks formed by gamma irradiation. Radiat Phys Chem 79(6):725–730CrossRefGoogle Scholar
  21. 21.
    Maziad NA, FIA EF, El-Kelesh NA, El-Hamouly SH, Zeid IF, Gayed HM (2016) Radiation synthesis and characterization of super absorbent hydrogels for controlled release of some agrochemicals. J Radioanal Nucl Chem 307(1):513–521CrossRefGoogle Scholar
  22. 22.
    Li N, Chen GX, Chen W, Huang JH, Tian JF, Wan XF, He MH, Zhang HF (2017) Multivalent cations-triggered rapid shape memory sodium carboxymethyl cellulose/polyacrylamide hydrogels with tunable mechanical strength. Carbohydr Polym 178:159–165PubMedCrossRefGoogle Scholar
  23. 23.
    Wu SP, Yu F, Dong H, Cao XD (2017) A hydrogel actuator with flexible folding deformation and shape programming via using sodium carboxymethyl cellulose and acrylic acid. Carbohydr Polym 173:526–534PubMedCrossRefGoogle Scholar
  24. 24.
    Vasile C, Bumbu GG, Dumitriu RP, Staikos G (2004) Comparative study of the behavior of carboxymethyl cellulose-g-poly(N-isopropylacrylamide) copolymers and their equivalent physical blends. Eur Polym J 40(6):1209–1215CrossRefGoogle Scholar
  25. 25.
    Ekici S (2011) Intelligent poly(N-isopropylacrylamide)-carboxymethyl cellulose full interpenetrating polymeric networks for protein adsorption studies. J Mater Sci 46(9):2843–2850CrossRefGoogle Scholar
  26. 26.
    Don TM, Huang ML, Chiu AC, Kuo KH, Chiu WY, Chiu LH (2008) Preparation of thermo-responsive acrylic hydrogels useful for the application in transdermal drug delivery systems. Mater Chem Phys 107(2–3):266–273CrossRefGoogle Scholar
  27. 27.
    Dutta S, Samanta P, Dhara D (2016) Temperature, pH and redox responsive cellulose based hydrogels for protein delivery. Int J Biol Macromol 87:92–100PubMedCrossRefGoogle Scholar
  28. 28.
    Patenaude M, Hoare T (2012) Injectable, mixed natural-synthetic polymer hydrogels with modular properties. Biomacromolecules 13(2):369–378PubMedCrossRefGoogle Scholar
  29. 29.
    Tran TH, Okabe H, Hidaka Y, Hara K (2017) Removal of metal ions from aqueous solutions using carboxymethyl cellulose/sodium styrene sulfonate gels prepared by radiation grafting. Carbohydr Polym 157:335–343PubMedCrossRefGoogle Scholar
  30. 30.
    Pourjavadi A, Ghasemzadeh H, Mojahedi F (2010) Swelling properties of CMC-g-poly (AAM-co-AMPS) superabsorbent hydrogel. J Appl Polym Sci 113(6):3442–3449CrossRefGoogle Scholar
  31. 31.
    Lam YC, Joshi SC, Tan BK (2007) Thermodynamic characteristics of gelation for methyl-cellulose hydrogels. J Therm Anal Calorim 87(2):475–482CrossRefGoogle Scholar
  32. 32.
    Zhang YL, Gao CJ, Li XL, Xu C, Zhang Y, Sun ZM, Liu Y, Gao JP (2014) Thermosensitive methyl cellulose-based injectable hydrogels for post-operation anti-adhesion. Carbohydr Polym 101:171–178PubMedCrossRefGoogle Scholar
  33. 33.
    Bortolin A, Aouada FA, Mattoso LHC, Ribeiro C (2013) Nanocomposite PAAm/methyl cellulose/montmorillonite hydrogel: evidence of synergistic effects for the slow release of fertilizers. J Agric Food Chem 61(31):7431–7439PubMedCrossRefGoogle Scholar
  34. 34.
    Aouada FA, Pan ZL, Orts WJ, Mattoso LHC (2009) Removal of paraquat pesticide from aqueous solutions using a novel adsorbent material based on polyacrylamide and methylcellulose hydrogels. J Appl Polym Sci 114(4):2139–2148CrossRefGoogle Scholar
  35. 35.
    Chen Q, Zhu L, Su XY, An HY (2011) Preparation and swelling dynamics research on polyacrylamide/methyl cellulose semi-interpenetrating polymer networks. Sci Technol Rev 29(29):38–43Google Scholar
  36. 36.
    Rassu M, Alzari V, Nuvoli D, Nuvoli L, Sanna D, Sanna V, Malucelli G, Mariani A (2017) Semi-interpenetrating polymer networks of methyl cellulose and polyacrylamide prepared by frontal polymerization. J Polym Sci A Polym Chem 55(7):1268–1274CrossRefGoogle Scholar
  37. 37.
    Stalling SS, Akintoye SO, Nicoll SB (2009) Development of photocrosslinked methylcellulose hydrogels for soft tissue reconstruction. Acta Biomater 5(6):1911–1918PubMedCrossRefGoogle Scholar
  38. 38.
    Samanta S, Das S, Layek RK, Chatterjee DP, Nandi AK (2012) Polythiophene-g-poly(dimethylaminoethyl methacrylate) doped methyl cellulose hydrogel behaving like a polymeric and logic gate. Soft Matter 8(22):6066–6072CrossRefGoogle Scholar
  39. 39.
    Das R, Pal S (2013) Hydroxypropyl methyl cellulose grafted with polyacrylamide: application in controlled release of 5-amino salicylic acid. Colloids Surf B Biointerfaces 110:236–241PubMedCrossRefGoogle Scholar
  40. 40.
    Das R, Panda AB, Pal S (2012) Synthesis and characterization of a novel polymeric hydrogel based on hydroxypropyl methyl cellulose grafted with polyacrylamide. Cellulose 19(3):933–945CrossRefGoogle Scholar
  41. 41.
    Xiao YL, Xia CC, Duan GY, Zhao XD (2011) Preparation and characterization of thermo-sensitive hydroxypropylmethyl cellulose/poly(N-isopropylacrylamide) hydrogel. Adv Mater Res 194-196:773–776CrossRefGoogle Scholar
  42. 42.
    Davaran S, Rashidi MR, Khani A (2007) Synthesis of chemically cross-linked hydroxypropyl methyl cellulose hydrogels and their application in controlled release of 5-amino salicylic acid. Drug Dev Ind Pharm 33(8):881–887PubMedCrossRefGoogle Scholar
  43. 43.
    Velickova E, Petrov P, Tsvetanov C, Kuzmanova S, Cvetkovska M, Winkelhausen E (2010) Entrapment of saccharomyces cerevisiae cells in u.V. Crosslinked hydroxyethylcellulose/ poly (ethylene oxide) double-layered gels. React Funct Polym 70(11):908–915CrossRefGoogle Scholar
  44. 44.
    Plungpongpan K, Koyanukkul K, Kaewvilai A, Nootsuwan N, Kewsuwan P, Laobuthee A (2013) Preparation of pvp/mhec blended hydrogels via gamma irradiation and their calcium ion uptaking and releasing ability. Energy Procedia 34:775–781CrossRefGoogle Scholar
  45. 45.
    Li QJ, Gong JX, Zhang JF (2015) Rheological properties and microstructures of hydroxyethyl cellulose/poly(acrylic acid) blend hydrogels. J Macromol Sci Part B Phys 54(9):1132–1143CrossRefGoogle Scholar
  46. 46.
    Wang JL, Wang WB, Zheng YA, Wang AQ (2011) Effects of modified vermiculite on the synthesis and swelling behaviors of hydroxyethyl cellulose-g-poly(acrylic acid)/vermiculite superabsorbent nanocomposites. J Polym Res 18(3):401–408CrossRefGoogle Scholar
  47. 47.
    Peng ZY, Chen FG (2010) Synthesis and properties of temperature-sensitive hydrogel based on hydroxyethyl cellulose. Int J Polym Mater 59(6):450–461CrossRefGoogle Scholar
  48. 48.
    Yamashita S, Hiroki A, Taguchi M (2014) Radiation-induced change of optical property of hydroxypropyl cellulose hydrogel containing methacrylate compounds: as a basis for development of a new type of radiation dosimeter. Radiat Phys Chem 101:53–58CrossRefGoogle Scholar
  49. 49.
    Marsano E, Bianchi E, Sciutto L (2003) Microporous thermally sensitive hydrogels based on hydroxypropyl cellulose crosslinked with poly-ethyleneglicol diglycidyl ether. Polymer 44(22):6835–6841CrossRefGoogle Scholar
  50. 50.
    Lei M, Hu JW, Lu MG, Tu YY, Chen X, Li YW, Lin SD, Li F, Hu SY (2016) Alkynyl-functionalization of hydroxypropyl cellulose and thermoresponsive hydrogel thereof prepared with P (NIPAAm-co-HEMAPCL). Carbohydr Polym 137:433–440CrossRefGoogle Scholar
  51. 51.
    Xu FJ, Zhu Y, Liu FS, Nie J, Ma J, Yang WT (2010) Comb-shaped conjugates comprising hydroxypropyl cellulose backbones and low-molecular-weight poly (N-isopropylacryamide) side chains for smart hydrogels: synthesis, characterization, and biomedical applications. Bioconjug Chem 21(3):456–464PubMedCrossRefGoogle Scholar
  52. 52.
    Hoo SP, Loh QL, Yue ZL, Fu J, Tan TTY, Choong C, Chan PPY (2013) Preparation of a soft and interconnected macroporous hydroxypropyl cellulose methacrylate scaffold for adipose tissue engineering. J Mater Chem B 1(24):3107–3117CrossRefGoogle Scholar
  53. 53.
    Zamarripa-Cerón JL, García-Cruz JC, Martínez-Arellano AC, Castro-Guerrero CF, Martín MEÁS, Morales-Cepeda AB (2016) Heavy metal removal using hydroxypropyl cellulose and polyacrylamide gels, kinetical study. J Appl Polym Sci 133(15):43285. Scholar
  54. 54.
    Castro-Guerrero CF, Morales-Cepeda A, Rivera-Armenta J, Mendoza-Martínez A, Álvarez-Castillo A (2008) Gels from acrylic acid and hydroxypropyl cellulose via free radical polymerization. E-Polymers 8(1):1697–1704CrossRefGoogle Scholar
  55. 55.
    George J, Sabapathi SN, Siddaramaiah (2015) Water soluble polymer-based nanocomposites containing cellulose nanocrystals. In: Eco-friendly polymer nanocomposites. Springer, New Delhi, pp 259–293Google Scholar
  56. 56.
    De France KJ, Hoare T, Cranston ED (2017) Review of hydrogels and aerogels containing nanocellulose. Chem Mater 29(11):4609–4631CrossRefGoogle Scholar
  57. 57.
    Tummala GK, Joffre T, Rojas R, Persson C, Mihranyan A (2017) Strain-induced stiffening of nanocellulose-reinforced poly(vinyl alcohol) hydrogels mimicking collagenous soft tissues. Soft Matter 13(21):3936–3945PubMedCrossRefGoogle Scholar
  58. 58.
    Chen X, Chen CT, Zhang H, Huang Y, Yang JZ, Sun DP (2017) Facile approach to the fabrication of 3D cellulose nanofibrils (CNFs) reinforced poly (vinyl alcohol) hydrogel with ideal biocompatibility. Carbohydr Polym 173:547–555PubMedCrossRefGoogle Scholar
  59. 59.
    Han JQ, Lei TZ, Wu QL (2013) Facile preparation of mouldable polyvinyl alcohol-borax hydrogels reinforced by well-dispersed cellulose nanoparticles: physical, viscoelastic and mechanical properties. Cellulose 20(6):2947–2958CrossRefGoogle Scholar
  60. 60.
    Abitbol T, Johnstone T, Quinn TM, Gray DG (2011) Reinforcement with cellulose nanocrystals of poly (vinyl alcohol) hydrogels prepared by cyclic freezing and thawing. Soft Matter 7(6):2373–2379CrossRefGoogle Scholar
  61. 61.
    Gonzalez JS, Ludueña LN, Ponce A, Alvarez VA (2014) Poly(vinyl alcohol)/cellulose nanowhiskers nanocomposite hydrogels for potential wound dressings. Mater Sci Eng C 34:54–61CrossRefGoogle Scholar
  62. 62.
    Xu ZY, Li JY, Zhou H, Jiang XD, Yang C, Wang F, Pan YY, Li NN, Li XY, Shi LN, Shi XM (2016) Morphological and swelling behavior of cellulose nanofiber (CNF)/poly(vinyl alcohol) (PVA) hydrogels: poly(ethylene glycol) (PEG) as porogen. RSC Adv 6(49):43626–43633CrossRefGoogle Scholar
  63. 63.
    Tummala GK, Rojas R, Mihranyan A (2016) Poly(vinyl alcohol) hydrogels reinforced with nanocellulose for ophthalmic applications: general characteristics and optical properties. J Phys Chem B 120(51):13094–13101PubMedCrossRefGoogle Scholar
  64. 64.
    Tummala GK, Joffre T, Lopes VR, Liszka A, Buznyk O, Ferraz N, Persson C, Griffith M, Mihranyan A (2016) Hyperelastic nanocellulose-reinforced hydrogel of high water content for ophthalmic applications. ACS Biomater Sci Eng 2(11):2072–2079CrossRefGoogle Scholar
  65. 65.
    Mckee JR, Appel EA, Seitsonen J, Kontturi E, Scherman OA, Ikkala O (2014) Healable, stable and stiff hydrogels: combining conflicting properties using dynamic and selective three-component recognition with reinforcing cellulose nanorods. Adv Funct Mater 24(18):2706–2713CrossRefGoogle Scholar
  66. 66.
    Mihranyan A (2013) Viscoelastic properties of cross-linked polyvinyl alcohol and surface-oxidized cellulose whisker hydrogels. Cellulose 20(3):1369–1376CrossRefGoogle Scholar
  67. 67.
    Anirudhan TS, Rejeena SR (2014) Poly (acrylic acid-co-acrylamide-co-2-acrylamido −2-methyl-1-propanesulfonic acid)-grafted nanocellulose/poly (vinyl alcohol) composite for the in vitro gastrointestinal release of amoxicillin. J Appl Polym Sci 131(17):40699. Scholar
  68. 68.
    Zhou YM, Fu SY, Zhang LL, Zhan HY, Levit MV (2014) Use of carboxylated cellulose nanofibrils-filled magnetic chitosan hydrogel beads as adsorbents for Pb(II). Carbohydr Polym 101:75–82PubMedCrossRefGoogle Scholar
  69. 69.
    Yue YY, Han JQ, Han GP, French AD, Qi YD, Wu QL (2016) Cellulose nanofibers reinforced sodium alginate-polyvinyl alcohol hydrogels: core-shell structure formation and property characterization. Carbohydr Polym 147:155–164PubMedCrossRefGoogle Scholar
  70. 70.
    Kobe R, Yoshitani K, Teramoto Y (2016) Fabrication of elastic composite hydrogels using surface-modified cellulose nanofiber as a multifunctional crosslinker. J Appl Polym Sci 133(4):42906. Scholar
  71. 71.
    Kobe R, Iwamoto S, Endo T, Yoshitani K, Teramoto Y (2016) Stretchable composite hydrogels incorporating modified cellulose nanofiber with dispersibility and polymerizability: mechanical property control and nanofiber orientation. Polymer 97:480–486CrossRefGoogle Scholar
  72. 72.
    Hebeish A, Farag S, Sharaf S, Shaheen TI (2014) Thermal responsive hydrogels based on semi interpenetrating network of poly(NIPAm) and cellulose nanowhiskers. Carbohydr Polym 102:159–166PubMedCrossRefGoogle Scholar
  73. 73.
    Wei JG, Chen YF, Liu HZ, Du CG, Yu HL, Zhou ZX (2016) Thermo-responsive and compression properties of tempo-oxidized cellulose nanofiber-modified pnipam hydrogels. Carbohydr Polym 147:201–207PubMedCrossRefGoogle Scholar
  74. 74.
    Wei JG, Chen YF, Liu HZ, Du CG, Yu HL, Ru J, Zhou ZX (2016) Effect of surface charge content in the tempo-oxidized cellulose nanofibers on morphologies and properties of poly (N -isopropylacrylamide)-based composite hydrogels. Ind Crop Prod 92:227–235CrossRefGoogle Scholar
  75. 75.
    Larsson E, Boujemaoui A, Malmstrom E, Carlmark A (2015) Thermoresponsive cryogels reinforced with cellulose nanocrystals. RSC Adv 5(95):77643–77650CrossRefGoogle Scholar
  76. 76.
    Zhou CJ, Wu QL, Yue YY, Zhang QG (2011) Application of rod-shaped cellulose nanocrystals in polyacrylamide hydrogels. J Colloid Interface Sci 353(1):116–123PubMedCrossRefGoogle Scholar
  77. 77.
    Zhou CJ, Wu QL, Zhang QG (2011) Dynamic rheology studies of in situ polymerization process of polyacrylamide-cellulose nanocrystal composite hydrogels. Colloid Polym Sci 289(3):247–255CrossRefGoogle Scholar
  78. 78.
    Yang J, Han CR, Duan JF, Ma MG, Zhang XM, Xu F, Sun RC (2013) Synthesis and characterization of mechanically flexible and tough cellulose nanocrystals- polyacrylamide nanocomposite hydrogels. Cellulose 20(1):227–237CrossRefGoogle Scholar
  79. 79.
    Yang J, Zhao JJ, Zhang XM (2014) Modification of cellulose nanocrystal-reinforced composite hydrogels: effects of co-crosslinked and drying treatment. Cellulose 21(5):3487–3496CrossRefGoogle Scholar
  80. 80.
    Yang J, Han CR, Duan JF, Ma MG, Zhang XM, Xu F, Sun RC, Xie XM (2012) Studies on the properties and formation mechanism of flexible nanocomposite hydrogels from cellulose nanocrystals and poly (acrylic acid). J Mater Chem 22(42):22467–22480CrossRefGoogle Scholar
  81. 81.
    Yang J, Zhao JJ, Xu F, Sun RC (2013) Revealing strong nanocomposite hydrogels reinforced by cellulose nanocrystals: insight into morphologies and interactions. ACS Appl Mater Interfaces 5(24):12960–12967PubMedCrossRefGoogle Scholar
  82. 82.
    Yang J, Han CR, Xu F, Sun RC (2014) Simple approach to reinforce hydrogels with cellulose nanocrystals. Nanoscale 6(11):5934–5943PubMedCrossRefGoogle Scholar
  83. 83.
    Yuan NX, Xu L, Zhang L, Ye HW, Zhao JH, Liu Z, Rong JH (2016) Superior hybrid hydrogels of polyacrylamide enhanced by bacterial cellulose nanofiber clusters. Mat Sci Eng C 67:221–230CrossRefGoogle Scholar
  84. 84.
    Yang J, Xu F (2017) Synergistic reinforcing mechanisms in cellulose nanofibrils composite hydrogels: interfacial dynamics, energy dissipation, and damage resistance. Biomacromolecules 18(8):2623–2632PubMedCrossRefGoogle Scholar
  85. 85.
    Yang J, Han CR, Zhang XM, Xu F, Sun RC (2014) Cellulose nanocrystals mechanical reinforcement in composite hydrogels with multiple cross-links: correlations between dissipation properties and deformation mechanisms. Macromolecules 47(12):4077–4086CrossRefGoogle Scholar
  86. 86.
    Mohamad N, Amin MCIM, Pandey M, Ahmad N, Rajab NF (2014) Bacterial cellulose/acrylic acid hydrogel synthesized via electron beam irradiation: accelerated burn wound healing in an animal model. Carbohydr Polym 114:312–320PubMedCrossRefGoogle Scholar
  87. 87.
    Amin MCIM, Ahmad N, Halib N, Ahmad I (2012) Synthesis and characterization of thermo- and ph-responsive bacterial cellulose/acrylic acid hydrogels for drug delivery. Carbohydr Polym 88(2):465–473CrossRefGoogle Scholar
  88. 88.
    Wen YB, Zhu XH, Gauthier DE, An XY, Cheng D, Ni YH, Yin LH (2015) Development of poly(acrylic acid)/nanofibrillated cellulose superabsorbent composites by ultraviolet light induced polymerization. Cellulose 22(4):2499–2506CrossRefGoogle Scholar
  89. 89.
    Bajpai SK, Pathak V, Soni B, Mohan YM (2014) CNWs loaded poly(SA) hydrogels: effect of high concentration of CNWs on water uptake and mechanical properties. Carbohydr Polym 106:351–358PubMedCrossRefGoogle Scholar
  90. 90.
    Di Z, Shi ZJ, Ullah MW, Li SX, Yang G (2017) A transparent wound dressing based on bacterial cellulose whisker and poly (2-hydroxyethyl methacrylate). Int J Biol Macromol 105:638–644PubMedCrossRefGoogle Scholar
  91. 91.
    Karaaslan MA, Tshabalala MA, Yelle DJ, Buschle-Diller G (2011) Nanoreinforced biocompatible hydrogels from wood hemicelluloses and cellulose whiskers. Carbohydr Polym 86(1):192–201CrossRefGoogle Scholar
  92. 92.
    Volynets B, Nakhoda H, Ghalia MA, Dahman Y (2017) Preparation and characterization of poly (2-hydroxyethyl methacrylate) grafted bacterial cellulose using atom transfer radical polymerization. Fibers Polym 18(5):859–867CrossRefGoogle Scholar
  93. 93.
    Shen XP, Shamshina JL, Paula B, Gurau G, Rogers RD (2016) Hydrogels based on cellulose and chitin: fabrication, properties, and applications. Green Chem 47(9):53–75CrossRefGoogle Scholar
  94. 94.
    Han S, Wang T, Yang L, Li B (2017) Building a bio-based hydrogel via electrostatic and host-guest interactions for realizing dual-controlled release mechanism. Int J Biol Macromol 105:377–384PubMedCrossRefGoogle Scholar
  95. 95.
    Wang YP, Qian JM, Zhao N, Liu T, Xu WJ, Suo AL (2017) Novel hydroxyethyl chitosan/cellulose scaffolds with bubble-like porous structure for bone tissue engineering. Carbohydr Polym 167:44–51PubMedCrossRefGoogle Scholar
  96. 96.
    Li N, Bai RB (2005) Copper adsorption on chitosan-cellulose hydrogel beads: behaviors and mechanisms. Sep Purif Technol 42(3):237–247CrossRefGoogle Scholar
  97. 97.
    Essawy HA, Ghazy MBM, Abd El-Hai F, Mohamed MF (2016) Superabsorbent hydrogels via graft polymerization of acrylic acid from chitosan-cellulose hybrid and their potential in controlled release of soil nutrients. Int J Biol Macromol 89:144–151PubMedCrossRefGoogle Scholar
  98. 98.
    Kaihara S, Suzuki Y, Fujimoto K (2011) In situ synthesis of polysaccharide nanoparticles via polyion complex of carboxymethyl cellulose and chitosan. Colloids Surf B Biointerfaces 85(2):343–348PubMedCrossRefGoogle Scholar
  99. 99.
    Benghanem S, Chetouani A, Elkolli M, Bounekhel M, Benachour D (2017) Grafting of oxidized carboxymethyl cellulose with hydrogen peroxide in presence of cu(II) to chitosan and biological elucidation. Biocybern Biomed Eng 37(1):94–102CrossRefGoogle Scholar
  100. 100.
    Jiang XL, Zhao Y, Peng YF, Han BQ, Li ZY, Li XH, Liu WS (2016) Preparation, characterization and feasibility study of dialdehyde carboxymethyl cellulose as a novel crosslinking reagent. Carbohydr Polym 137:632–641PubMedCrossRefGoogle Scholar
  101. 101.
    Weng LH, Le HC, Lin JY, Golzarian J (2011) Doxorubicin loading and eluting characteristics of bioresorbable hydrogel microspheres: in vitro study. Int J Pharm 409(1–2):185–193PubMedCrossRefGoogle Scholar
  102. 102.
    Weng LH, Rostambeigi N, Zantek ND, Rostamzadeh P, Bravo M, Carey J, Golzarian J (2013) An in situ forming biodegradable hydrogel-based embolic agent for interventional therapies. Acta Biomater 9(9):8182–8191PubMedCrossRefGoogle Scholar
  103. 103.
    Fan LH, Tan C, Wang LB, Pan XR, Cao M, Wen F, Xie WG, Nie M (2013) Preparation, characterization and the effect of carboxymethylated chitosan–cellulose derivatives hydrogels on wound healing. J Appl Polym Sci 128(5):2789–2796CrossRefGoogle Scholar
  104. 104.
    Kimura S, Isobe N, Wada M, Kuga S, Ko JH, Kim UJ (2011) Enzymatic hydrolysis of chitosan-dialdehyde cellulose hydrogels. Carbohydr Polym 83(4):1850–1853CrossRefGoogle Scholar
  105. 105.
    Yoshii F, Zhao L, Wach RA, Nagasawa N, Mitomo H, Kume T (2003) Hydrogels of polysaccharide derivatives crosslinked with irradiation at paste-like condition. Nucl Instrum Methods Phys Res B 208:320–324CrossRefGoogle Scholar
  106. 106.
    Hiroki A, Tran HT, Nagasawa N, Yagi T, Tamada M (2009) Metal adsorption of carboxymethyl cellulose/carboxymethyl chitosan blend hydrogels prepared by gamma irradiation. Radiat Phys Chem 78(12):1076–1080CrossRefGoogle Scholar
  107. 107.
    Wach RA, Mitomo H, Nagasawa N, Yoshii F (2003) Radiation crosslinking of carboxymethylcellulose of various degree of substitution at high concentration in aqueous solutions of natural pH. Radiat Phys Chem 68(5):771–779CrossRefGoogle Scholar
  108. 108.
    Zhao L, Mitomo H, Nagasawa N, Yoshii F, Kume T (2003) Radiation synthesis and characteristic of the hydrogels based on carboxymethylated chitin derivatives. Carbohydr Polym 51(2):169–175CrossRefGoogle Scholar
  109. 109.
    Yan LF, Qian F, Zhu QS (2001) Interpolymer complex polyampholytic hydrogel of chitosan and carboxymethyl cellulose (CMC): synthesis and ion effect. Polym Int 50(12):1370–1374CrossRefGoogle Scholar
  110. 110.
    Wang M, Xu L, Zhai ML, Peng J, Li JQ, Wei GS (2008) Gamma-ray radiation-induced synthesis and Fe(III) ion adsorption of carboxymethylated chitosan hydrogels. Carbohydr Polym 74(3):498–503CrossRefGoogle Scholar
  111. 111.
    Wach RA, Mitomo H, Yoshii F (2004) ESR investigation on gamma-irradiated methylcellulose and hydroxyethylcellulose in dry state and in aqueous solution. J Radioanal Nucl Chem 261(1):113–118CrossRefGoogle Scholar
  112. 112.
    Barros SC, da Silva AA, Costa DB, Cesarino I, Costa CM, Lanceros-Méndez S, Pawlicka A, Silva MM (2014) Thermo-sensitive chitosan-cellulose derivative hydrogels: swelling behaviour and morphologic studies. Cellulose 21(6):4531–4544CrossRefGoogle Scholar
  113. 113.
    Barros SC, da Silva AA, Costa DB, Costa CM, Lanceros-Méndez S, Maciavello MNT, Ribelles JLG, Sentanin F, Pawlicka A, Silva MM (2015) Thermal-mechanical behaviour of chitosan-cellulose derivative thermoreversible hydrogel films. Cellulose 22(3):1911–1929CrossRefGoogle Scholar
  114. 114.
    Yan SF, Yin JB, Tang L, Chen XS (2011) Novel physically crosslinked hydrogels of carboxymethyl chitosan and cellulose ethers: structure and controlled drug release behavior. J Appl Polym Sci 119(4):2350–2358CrossRefGoogle Scholar
  115. 115.
    Bhattarai N, Gunn J, Zhang MQ (2010) Chitosan-based hydrogels for controlled, localized drug delivery. Adv Drug Deliv Rev 62(1):83–99PubMedCrossRefGoogle Scholar
  116. 116.
    Vashist A, Gupta YK, Ahmad S (2012) Interpenetrating biopolymer network based hydrogels for an effective drug delivery system. Carbohydr Polym 87(2):1433–1439CrossRefGoogle Scholar
  117. 117.
    Kim MH, An S, Won K, Kim HJ, Lee SH (2012) Entrapment of enzymes into cellulose-biopolymer composite hydrogel beads using biocompatible ionic liquid. J Mol Catal B Enzym 75:68–72CrossRefGoogle Scholar
  118. 118.
    Liu Z, Wang HS, Liu C, Jiang YJ, Yu G, Mu XD, Wang XY (2012) Magnetic cellulose-chitosan hydrogels prepared from ionic liquids as reusable adsorbent for removal of heavy metal ions. Chem Commun 48(59):7350–7352CrossRefGoogle Scholar
  119. 119.
    Wang YY, Hong CT, Chiu WT, Fang JY (2001) In vitro and in vivo evaluations of topically applied capsaicin and nonivamide from hydrogels. Int J Pharm 224(1–2):89–104PubMedCrossRefGoogle Scholar
  120. 120.
    Mitsumata T, Suemitsu Y, Fujii K, Fujii T, Taniguchi T, Koyama K (2003) pH-response of chitosan, κ-carrageenan, carboxymethyl cellulose sodium salt complex hydrogels. Polymer 44(23):7103–7111CrossRefGoogle Scholar
  121. 121.
    Gaihre B, Jayasuriya AC (2016) Fabrication and characterization of carboxymethyl cellulose novel microparticles for bone tissue engineering. Mater Sci Eng C 69:733–743CrossRefGoogle Scholar
  122. 122.
    Lai YL, Annadurai G, Huang FC, Lee JF (2008) Biosorption of Zn(II) on the different ca-alginate beads from aqueous solution. Bioresour Technol 99(14):6480–6487PubMedCrossRefGoogle Scholar
  123. 123.
    Dewangan T, Tiwari A, Bajpai AK (2011) Removal of chromium(VI) ions by adsorption onto binary biopolymeric beads of sodium alginate and carboxymethyl cellulose. J Dispers Sci Technol 32(8):1075–1082CrossRefGoogle Scholar
  124. 124.
    Dewangan T, Tiwari A, Bajpai AK (2010) Adsorption of hg(II) ions onto binary biopolymeric beads of carboxymethyl cellulose and alginate. J Dispers Sci Technol 31(6):844–851CrossRefGoogle Scholar
  125. 125.
    Agarwal T, Narayana SNGH, Pal K, Pramanik K, Giri S, Banerjee I (2015) Calcium alginate-carboxymethyl cellulose beads for colon-targeted drug delivery. Int J Biol Macromol 75:409–417PubMedCrossRefGoogle Scholar
  126. 126.
    Banerjee S, Singh S, Bhattacharya SS, Chattopadhyay P (2013) Trivalent ion cross-linked pH sensitive alginate-methyl cellulose blend hydrogel beads from aqueous template. Int J Biol Macromol 57:297–307PubMedCrossRefGoogle Scholar
  127. 127.
    Thi HAM, Van NT, Van VML (2013) Biochemical studies on the immobilized lactase in the combined alginate-carboxymethyl cellulose gel. Biochem Eng J 74(7):81–87Google Scholar
  128. 128.
    Thomas M, Naikoo GA, Sheikh MUD, Bano M, Khan F (2016) Effective photocatalytic degradation of Congo red dye using alginate/carboxymethyl cellulose/TiO2, nanocomposite hydrogel under direct sunlight irradiation. J Photochem Photobiol A 327:33–43CrossRefGoogle Scholar
  129. 129.
    Wang Q, Wang WB, Wu J, Wang AQ (2012) Effect of attapulgite contents on release behaviors of a pH sensitive carboxymethyl cellulose-g-poly(acrylic acid)/attapulgite/ sodium alginate composite hydrogel bead containing diclofenac. J Appl Polym Sci 124(6):4424–4432Google Scholar
  130. 130.
    Chiaoprakobkij N, Sanchavanakit N, Subbalekha K, Pavasant P, Phisalaphong M (2011) Characterization and biocompatibility of bacterial cellulose/alginate composite sponges with human keratinocytes and gingival fibroblasts. Carbohydr Polym 85(3):548–553CrossRefGoogle Scholar
  131. 131.
    Park MS, Lee DJ, Hyun JH (2015) Nanocellulose-alginate hydrogel for cell encapsulation. Carbohydr Polym 116:223–228PubMedCrossRefGoogle Scholar
  132. 132.
    Kirdponpattara S, Khamkeaw A, Sanchavanakit N, Pavasant P, Phisalaphong M (2015) Structural modification and characterization of bacterial cellulose-alginate composite scaffolds for tissue engineering. Carbohydr Polym 132:146–155PubMedCrossRefGoogle Scholar
  133. 133.
    Shao W, Liu H, Liu XF, Wang SX, Wu JM, Zhang R, Min MH, Huang M (2015) Development of silver sulfadiazine loaded bacterial cellulose/sodium alginate composite films with enhanced antibacterial property. Carbohydr Polym 132:351–358PubMedCrossRefGoogle Scholar
  134. 134.
    Shi XN, Zheng YD, Wang C, Yue LN, Qiao K, Wang GJ, Wang LN, Quan HY (2015) Dual stimulus responsive drug releasing under the interaction of ph value and pulsatile electric field for bacterial cellulose/sodium alginate/multi-walled carbon nanotubes hybrid hydrogel. RSC Adv 5(52):41820–41829CrossRefGoogle Scholar
  135. 135.
    Kim JH, Park S, Kim H, Kim HJ, Yang YH, Kim YH, Jung SK, Kan E, Lee SH (2017) Alginate/bacterial cellulose nanocomposite beads prepared using gluconacetobacter xylinus and their application in lipase immobilization. Carbohydr Polym 157:137–145PubMedCrossRefGoogle Scholar
  136. 136.
    Kirdponpattara S, Phisalaphong M (2013) Bacterial cellulose-alginate composite sponge as a yeast cell carrier for ethanol production. Biochem Eng J 77:103–109CrossRefGoogle Scholar
  137. 137.
    Mohamed MA (2012) Swelling characteristics and application of gamma-radiation on irradiated SBR-carboxymethylcellulose (CMC) blends. Arab J Chem 5(2):207–211CrossRefGoogle Scholar
  138. 138.
    Bhattacharya SS, Ghosh AK, Banerjee S, Chattopadhyay P, Ghosh A (2012) Al3+ ion cross-linked interpenetrating polymeric network microbeads from tailored natural polysaccharides. Int J Biol Macromol 51(5):1173–1184PubMedCrossRefGoogle Scholar
  139. 139.
    Kim MS, Park SJ, Gu BK, Kim CH (2012) Ionically crosslinked alginate–carboxymethyl cellulose beads for the delivery of protein therapeutics. Appl Surf Sci 262(13):28–33CrossRefGoogle Scholar
  140. 140.
    Swamy BY, Yun YS (2015) In vitro release of metformin from iron (III) cross-linked alginate-carboxymethyl cellulose hydrogel beads. Int J Biol Macromol 77:114–119PubMedCrossRefGoogle Scholar
  141. 141.
    Tsirigotis-Maniecka M, Gancarz R, Wilk KA (2017) Polysaccharide hydrogel particles for enhanced delivery of hesperidin: fabrication, characterization and in vitro evaluation. Colloids Surf A Physicochem Eng Asp 532:48–56CrossRefGoogle Scholar
  142. 142.
    Ren HX, Gao ZM, Wu DJ, Jiang JH, Sun YM, Luo CW (2016) Efficient Pb(II) removal using sodium alginate-carboxymethyl cellulose gel beads: preparation, characterization, and adsorption mechanism. Carbohydr Polym 137:402–409PubMedCrossRefGoogle Scholar
  143. 143.
    Işiklan N (2006) Controlled release of insecticide carbaryl from sodium alginate, sodium alginate/gelatin, and sodium alginate/sodium carboxymethyl cellulose blend beads crosslinked with glutaraldehyde. J Appl Polym Sci 99(4):1310–1319CrossRefGoogle Scholar
  144. 144.
    Al-Kahtani AA, Sherigara BS (2014) Controlled release of diclofenac sodium through acrylamide grafted hydroxyethyl cellulose and sodium alginate. Carbohydr Polym 104(104):151–157PubMedCrossRefGoogle Scholar
  145. 145.
    Chang CY, Duan B, Zhang LN (2009) Fabrication and characterization of novel macroporous cellulose-alginate hydrogels. Polymer 50(23):5467–5473CrossRefGoogle Scholar
  146. 146.
    Bang S, Ko YG, Kim WII, Cho D, Park WH, Kwon OH (2017) Preventing postoperative tissue adhesion using injectable carboxymethyl cellulose-pullulan hydrogels. Int J Biol Macromol 105:886–893PubMedCrossRefGoogle Scholar
  147. 147.
    Pathak VM, Kumar N (2017) Dataset on the superabsorbent hydrogel synthesis with SiO2 nanoparticle and role in water restoration capability of agriculture soil. Data Brief 13:291–294PubMedPubMedCentralCrossRefGoogle Scholar
  148. 148.
    Gomes RF, de Neto A, Antonio C, Pereira AGB, Muniz EC, Fajardo AR, Rodrigues FHA (2015) Fast dye removal from water by starch-based nanocomposites. J Colloid Interface Sci 454:200–209PubMedCrossRefGoogle Scholar
  149. 149.
    Spagnol C, Rodrigues FHA, Pereira AGB, Fajardo AR, Rubira AF, Muniz EC (2012) Superabsorbent hydrogel nanocomposites based on starch-g-poly(sodium acrylate) matrix filled with cellulose nanowhiskers. Cellulose 19(4):1225–1237CrossRefGoogle Scholar
  150. 150.
    Liu ZJ, Huang HH (2016) Preparation and characterization of cellulose composite hydrogels from tea residue and carbohydrate additives. Carbohydr Polym 147:226–233PubMedCrossRefGoogle Scholar
  151. 151.
    Hu XY, Wang J, Huang HH (2013) Impacts of some macromolecules on the characteristics of hydrogels prepared from pineapple peel cellulose using ionic liquid. Cellulose 20:2923–2933CrossRefGoogle Scholar
  152. 152.
    Michailova V, Titeva S, Kotsilkova R, Krusteva E, Minkov E (2001) Influence of hydrogel structure on the processes of water penetration and drug release from mixed hydroxypropylmethyl cellulose/thermally pregelatinized waxy maize starch hydrophilic matrices. Int J Pharm 222(1):7–17PubMedCrossRefGoogle Scholar
  153. 153.
    Nagasawa N, Yagi T, Kume T, Yoshii F (2004) Radiation crosslinking of carboxymethyl starch. Carbohydr Polym 58(2):109–113CrossRefGoogle Scholar
  154. 154.
    Othman Z, Hassan O, Hashim K (2015) Physicochemical and thermal properties of gamma-irradiated sago (metroxylon sagu) starch. Radiat Phys Chem 109:48–53CrossRefGoogle Scholar
  155. 155.
    Basri SN, Zainuddin N, Hashim K, Yusof NA (2016) Preparation and characterization of irradiated carboxymethyl sago starch-acid hydrogel and its application as metal scavenger in aqueous solution. Carbohydr Polym 138:34–40PubMedCrossRefGoogle Scholar
  156. 156.
    Senna MM, Mostafa AEKB, Mahdy SR, El-Naggar AWM (2016) Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation. Nucl Instrum Methods Phys Res B 386:22–29CrossRefGoogle Scholar
  157. 157.
    Tan HL, Wong YY, Muniyandy S, Hashim K, Pushpamalar J (2016) Carboxymethyl sago pulp/carboxymethyl sago starch hydrogel: effect of polymer mixing ratio and study of controlled drug release. J Appl Polym Sci 133(28):43652. Scholar
  158. 158.
    Fekete T, Borsa J, Takács E, Wojnárovits L (2017) Synthesis of carboxymethylcellulose/ starch superabsorbent hydrogels by gamma-irradiation. Chem Cent J 11:46PubMedPubMedCentralCrossRefGoogle Scholar
  159. 159.
    Liu SM, Luo WC, Huang HH (2016) Characterization and behavior of composite hydrogel prepared from bamboo shoot cellulose and β-cyclodextrin. Int J Biol Macromol 89:527–534PubMedCrossRefGoogle Scholar
  160. 160.
    Badruddoza AZM, Tay ASH, Tan PY, Hidajat K, Uddin MS (2011) Carboxymethyl-β-cyclodextrin conjugated magnetic nanoparticles as nano-adsorbents for removal of copper ions: synthesis and adsorption studies. J Hazard Mater 185(2–3):1177–1186PubMedCrossRefGoogle Scholar
  161. 161.
    Goto H, Furusho Y, Yashima E (2007) Supramolecular control of unwinding and rewinding of a double helix of oligoresorcinol using cyclodextrin/adamantane system. J Am Chem Soc 129(1):109–112PubMedCrossRefGoogle Scholar
  162. 162.
    Zhang LZ, Zhou JP, Zhang LN (2013) Structure and properties of β-cyclodextrin/ cellulose hydrogels prepared in naoh/urea aqueous solution. Carbohydr Polym 94(1):386–393PubMedCrossRefGoogle Scholar
  163. 163.
    Ghorpade VS, Yadav AV, Dias RJ (2016) Citric acid crosslinked cyclodextrin/ hydroxypropylmethyl cellulose hydrogel films for hydrophobic drug delivery. Int J Biol Macromol 93:75–86PubMedCrossRefGoogle Scholar
  164. 164.
    Ghorpade VS, Yadav AV, Dias RJ (2017) Citric acid crosslinked β -cyclodextrin/ carboxymethylcellulose hydrogel films for controlled delivery of poorly soluble drugs. Carbohydr Polym 164:339–348PubMedCrossRefGoogle Scholar
  165. 165.
    Rodriguez-Tenreiro C, Alvarez-Lorenzo C, Rodriguez-Perez A, Concheiro A, Torres-Labandeira JJ (2006) New cyclodextrin hydrogels cross-linked with diglycidylethers with a high drug loading and controlled release ability. Pharm Res 23(1):121–130PubMedCrossRefGoogle Scholar
  166. 166.
    Pinho E, Henriques M, Soares G (2014) Cyclodextrin/cellulose hydrogel with gallic acid to prevent wound infection. Cellulose 21(6):4519–4530CrossRefGoogle Scholar
  167. 167.
    Medronho B, Duarte H, Alves L, Antunes FE, Romano A, Valente AJM (2016) The role of cyclodextrin-tetrabutyl ammonium complexation on the cellulose dissolution. Carbohydr Polym 140:136–143PubMedCrossRefGoogle Scholar
  168. 168.
    Medronho B, Duarte H, Magalhães S, Alves L, Valente AJM, Romano A (2017) From a new cellulose solvent to the cyclodextrin induced formation of hydrogels. Colloids Surf A Physicochem Eng Asp 532:548–555CrossRefGoogle Scholar
  169. 169.
    Duan JF, Zhang XJ, Jiang JX, Han CR, Yang J, Liu LJ, Lan HY, Huang DZ (2014) The synthesis of a novel cellulose physical gel. J Nanomater 2014:312696CrossRefGoogle Scholar
  170. 170.
    Sun N, Wang T, Yan XF (2017) Self-assembled supermolecular hydrogel based on hydroxyethyl cellulose: formation, in vitro release and bacteriostasis application. Carbohydr Polym 172:49–59PubMedCrossRefGoogle Scholar
  171. 171.
    Lin N, Dufresne A (2013) Supramolecular hydrogels from in situ host-guest inclusion between chemically modified cellulose nanocrystals and cyclodextrin. Biomacromolecules 14(3):871–880PubMedCrossRefGoogle Scholar
  172. 172.
    Mourtas S, Aggelopoulos CA, Klepetsanis P, Tsakiroglou CD, Antimisiaris SG (2009) Complex hydrogel systems composed of polymers, liposomes, and cyclodextrins: implications of composition on rheological properties and aging. Langmuir 25(15):8480–8488PubMedCrossRefGoogle Scholar
  173. 173.
    Kato N, Tanaka T, Nakagawa S, Morohoshi T, Hiratani K, Ikeda T (2007) Control of virulence factor expression in opportunistic pathogens using cyclodextrin immobilized gel. J Incl Phenom Macrocycl Chem 57(1–4):419–423CrossRefGoogle Scholar
  174. 174.
    Pose-Vilarnovo B, Rodríguez-Tenreiro C, dos JFR S, Vázquez-Doval J, Concheiro A, Alvarez-Lorenzo C, Torres-Labandeira JJ (2004) Modulating drug release with cyclodextrins in hydroxypropyl methylcellulose gels and tablets. J Control Release 94(2–3):351–363PubMedCrossRefGoogle Scholar
  175. 175.
    Theocharis AD, Skandalis SS, Gialeli C, Karamanos NK (2016) Extracellular matrix structure. Adv Drug Deliv Rev 97:4–27PubMedCrossRefGoogle Scholar
  176. 176.
    Badylak SF (2007) The extracellular matrix as a biologic scaffold material. Biomaterials 28(25):3587–3593PubMedCrossRefGoogle Scholar
  177. 177.
    Gelse K, Pöschl E, Aigner T (2003) Collagens-structure, function, and biosynthesis. Adv Drug Deliv Rev 55(12):1531–1546PubMedCrossRefGoogle Scholar
  178. 178.
    Kanth SV, Ramaraj A, Rao JR, Nair BU (2009) Stabilization of type I collagen using dialdehyde cellulose. Process Biochem 44(8):869–874CrossRefGoogle Scholar
  179. 179.
    Pietrucha K, Safandowska M (2015) Dialdehyde cellulose-crosslinked collagen and its physicochemical properties. Process Biochem 50(12):2105–2111CrossRefGoogle Scholar
  180. 180.
    Cheng YM, Lu JT, Liu SL, Zhao P, Lu GZ, Chen JH (2014) The preparation, characterization and evaluation of regenerated cellulose/collagen composite hydrogel films. Carbohydr Polym 107:57–64PubMedCrossRefGoogle Scholar
  181. 181.
    Li HL, Wu B, Mu CD, Lin W (2011) Concomitant degradation in periodate oxidation of carboxymethyl cellulose. Carbohydr Polym 84(3):881–886CrossRefGoogle Scholar
  182. 182.
    Tan H, Wu B, Li CP, Mu CD, Li HL, Lin W (2015) Collagen cryogel cross-linked by naturally derived dialdehyde carboxymethyl cellulose. Carbohydr Polym 129:17–24PubMedCrossRefGoogle Scholar
  183. 183.
    Pei Y, Wang XY, Huang WH, Liu P, Zhang LN (2013) Cellulose-based hydrogels with excellent microstructural replicationability and cytocompatibility for microfluidic devices. Cellulose 20(4):1897–1909CrossRefGoogle Scholar
  184. 184.
    Dai J, Yang H, Yan H, Shangguan YG, Zheng Q, Cheng RS (2011) Phosphate adsorption from aqueous solutions by disused adsorbents: chitosan hydrogel beads after the removal of copper(II). Chem Eng J 166(3):970–977CrossRefGoogle Scholar
  185. 185.
    Wang JL, Wei LG, Ma YC, Li KL, Li MH, Yu YC, Wang L, Qiu HH (2013) Collagen/cellulose hydrogel beads reconstituted from ionic liquid solution for cu(II) adsorption. Carbohydr Polym 98(1):736–743PubMedCrossRefGoogle Scholar
  186. 186.
    Cai ZJ, Yang G (2015) Bacterial cellulose/collagen composite: characterization and first evaluation of cytocompatibility. J Appl Polym Sci 120(5):2938–2944Google Scholar
  187. 187.
    Fontes de Sousa Moraes PR, Saska S, Barud H, Saska S, Barud H, LRD L, VDCA M, AMDG P, SJL R, AMM G (2016) Bacterial cellulose/collagen hydrogel for wound healing. Mater Res-Ibero-Am J 19(1):106–116Google Scholar
  188. 188.
    Lin YK, Chen KH, Ou KL, Liu M (2011) Effects of different extracellular matrices and growth factor immobilization on biodegradability and biocompatibility of macroporous bacterial cellulose. J Bioact Compat Polym 26(5):508–518CrossRefGoogle Scholar
  189. 189.
    Yang Q, Ma H, Dai ZW, Wang JF, Dong SW, Shen JJ, Dong J (2017) Improved thermal and mechanical properties of bacterial cellulose with the introduction of collagen. Cellulose 24(9):3777–3787CrossRefGoogle Scholar
  190. 190.
    Sampath UGTM, Ching YC, Cheng HC, Singh R, Lin PC (2017) Preparation and characterization of nanocellulose reinforced semi-interpenetrating polymer network of chitosan hydrogel. Cellulose 24(5):2215–2228CrossRefGoogle Scholar
  191. 191.
    Gunathilake TMSU, Ching YC, Cheng HC (2017) Enhancement of curcumin bioavailability using nanocellulose reinforced chitosan hydrogel. Polymers 9(2):64. Scholar
  192. 192.
    Yang H, Sheikhi A, van de Ven TG (2016) Reusable green aerogels from crosslinked hairy nanocrystalline cellulose and modified chitosan for dye removal. Langmuir 32(45):11771–11779PubMedCrossRefGoogle Scholar
  193. 193.
    Sukul M, Ventura RD, Bae SH, Choi HJ, Lee SY, Lee BT (2017) Plant-derived oxidized nanofibrillar cellulose-chitosan composite as an absorbable hemostat. Mater Lett 197:150–155CrossRefGoogle Scholar
  194. 194.
    Lai C, Zhang SJ, Chen XC, Sheng LY (2014) Nanocomposite films based on tempo–mediated oxidized bacterial cellulose and chitosan. Cellulose 21(4):2757–2772CrossRefGoogle Scholar
  195. 195.
    Spagnol C, Rodrigues FHA, Pereira AGB, Fajardo AR, Rubira AF, Muniz EC (2012) Superabsorbent hydrogel composite made of cellulose nanofibrils and chitosan-graft- poly(acrylic acid). Carbohydr Polym 87(3):2038–2045CrossRefGoogle Scholar
  196. 196.
    Rao KM, Kumar A, Han SS (2017) Polysaccharide based bionanocomposite hydrogels reinforced with cellulose nanocrystals: drug release and biocompatibility analyses. Int J Biol Macromol 101:165–171CrossRefGoogle Scholar
  197. 197.
    Ul-Islam M, Khan T, Park JK (2012) Water holding and release properties of bacterial cellulose obtained by in situ and ex situ modification. Carbohydr Polym 88(2):596–603CrossRefGoogle Scholar
  198. 198.
    Kim HJ, Jin JN, Kan E, Kim KJ, Lee SH (2017) Bacterial cellulose-chitosan composite hydrogel beads for enzyme immobilization. Biotechnol Bioprocess Eng 22(1):89–94CrossRefGoogle Scholar
  199. 199.
    Jia YY, Wang XH, Huo MM, Zhai XL, Li F, Zhong C (2017) Preparation and characterization of a novel bacterial cellulose/chitosan bio-hydrogel. Nanomater Nanotechno 7. Scholar
  200. 200.
    Mohammed N, Grishkewich N, Waeijen HA, Berry RM, Tam KC (2016) Continuous flow adsorption of methylene blue by cellulose nanocrystal-alginate hydrogel beadsin fixed bed columns. Carbohydr Polym 136:1194–1202PubMedCrossRefGoogle Scholar
  201. 201.
    Mohammed N, Grishkewich N, Berry RM, Tam KC (2015) Cellulose nanocrystal-alginate hydrogel beads as novel adsorbents for organic dyes in aqueoussolutions. Cellulose 22(6):3725–3738CrossRefGoogle Scholar
  202. 202.
    Suratago T, Taokaew S, Kanjanamosit N, Kanjanaprapakul K, Burapatana V, Phisalaphong M (2015) Development of bacterial cellulose/alginate nanocomposite membrane for separation of ethanol-water mixtures. J Ind Eng Chem 32:305–312CrossRefGoogle Scholar
  203. 203.
    Leppiniemi J, Lahtinen P, Paajanen A, Mahlberg R, Metsä-Kortelainen S, Pinomaa T, Pajari H, Vikholm-Lundin I, Pursula P, Hytönen VP (2017) 3D-printable bioactivated Nanocellulose-alginate hydrogels. ACS Appl Mater Interfaces 9(26):21959–21970PubMedCrossRefGoogle Scholar
  204. 204.
    Naseri N, Deepa B, Mathew AP, Oksman K, Girandon L (2016) Nanocellulose- based interpenetrating polymer network (IPN) hydrogels for cartilage applications. Biomacromolecules 17(11):3714–3723PubMedCrossRefGoogle Scholar
  205. 205.
    Lin N, Geze A, Wouessidjewe D, Huang J, Dufresne A (2016) Biocompatible double-membrane hydrogels from cationic cellulose nanocrystals and anionic alginate as complexing drugs Codelivery. ACS Appl Mater Interfaces 8(11):6880–6889PubMedCrossRefGoogle Scholar
  206. 206.
    Dai QZ, Kadla JF (2009) Effect of Nanofillers on Carboxymethyl cellulose/ hydroxyethyl cellulose hydrogels. J Appl Polym Sci 114(3):1664–1669CrossRefGoogle Scholar
  207. 207.
    Mckee JR, Hietala S, Seitsonen J, Laine J, Kontturi E, Ikkala O (2014) Thermoresponsive Nanocellulose hydrogels with tunable mechanical properties. ACS Macro Lett 3(3):266–270CrossRefGoogle Scholar
  208. 208.
    Yang X, Bakaic E, Hoare T, Cranston ED (2013) Injectable polysaccharide hydrogels reinforced with cellulose nanocrystals: morphology, rheology, degradation, and Cytotoxicityv. Biomacromolecules 14(12):4447–4455PubMedCrossRefGoogle Scholar
  209. 209.
    Zhou YM, Fu SY, Zhang LL, Zhan HY (2013) Superabsorbent nanocomposite hydrogels made of carboxylated cellulose nanofibrils and CMC-g-p(AA-co-AM). Carbohydr Polym 97(2):429–435PubMedCrossRefGoogle Scholar
  210. 210.
    Nakayama A, Kakugo A, Gong JP, Osada Y, Takai M, Erata T, Kawano S (2004) High mechanical strength double-network hydrogel with bacterial cellulose. Adv Funct Mater 14(11):1124–1128CrossRefGoogle Scholar
  211. 211.
    Wang WH, Zhang XW, Teng AG, Liu AJ (2017) Mechanical reinforcement of gelatin hydrogel with nanofiber cellulose as a function of percolation concentration. Int J Biol Macromol 103:226–233PubMedCrossRefGoogle Scholar
  212. 212.
    Li WC, Lan Y, Guo R, Zhang Y, Xue W, Zhang YM (2015) In vitro and in vivo evaluation of a novel collagen/cellulose nanocrystals scaffold for achievingthe sustained release of basic fibroblast growth factor. J Biomater Appl 29(6):882–893PubMedCrossRefGoogle Scholar
  213. 213.
    Mathew AP, Oksman K, Pierron D, Harmad MF (2012) Crosslinked fibrous composites based on cellulose nanofibers and collagen with in situ pHinduced fibrillation. Cellulose 19(1):139–150CrossRefGoogle Scholar
  214. 214.
    Mathew AP, Oksman K, Pierron D, Harmand MF (2013) Biocompatible fibrous networks of cellulose Nanofibres and collagen crosslinked using Genipin: potential as artificial ligament/tendons. Macromol Biosci 13(3):289–298PubMedCrossRefGoogle Scholar
  215. 215.
    Lu TH, Li Q, Chen WS, Yu HP (2014) Composite aerogels based on dialdehyde nanocellulose and collagen for potential applicationsas wound dressing and tissue engineering scaffold. Compos Sci Technol 94:132–138CrossRefGoogle Scholar
  216. 216.
    Mauricio MR, da Coster PG, Haraguchi SK, Guilherme MR, Muniz EC, Rubira AF (2015) Synthesis of a microhydrogel composite from cellulose nanowhiskers and starch for drugdelivery. Carbohydr Polym 115:715–722PubMedCrossRefGoogle Scholar
  217. 217.
    Chiu CW, Lin JJ (2012) Self-assembly behavior of polymer-assisted clays. Prog Polym Sci 37(3):406–444CrossRefGoogle Scholar
  218. 218.
    Zafar R, Zia KM, Tabasum S, Jabeen F, Noreen A, Zuber M (2016) Polysaccharide based bionanocomposites, properties and applications: a review. Int J Biol Macromol 92:1012–1024PubMedCrossRefGoogle Scholar
  219. 219.
    Liu Y, Wang WB, Jin YL, Wang AQ (2011) Adsorption behavior of methylene blue from aqueous solution by the hydrogel CompositesBased on Attapulgite. Sep Sci Technol 46(5):858–868CrossRefGoogle Scholar
  220. 220.
    Bao Y, Ma JZ, Li N (2011) Synthesis and swelling behaviors of sodium carboxymethyl cellulose-g-poly(AA-co-AM-co-AMPS)/MMT superabsorbent hydrogel. Carbohydr Polym 84(1):76–82CrossRefGoogle Scholar
  221. 221.
    Bao Y, Ma JZ, Sun YG (2012) Swelling behaviors of organic/inorganic composites based on various cellulose derivatives and inorganic particles. Carbohydr Polym 88(2):589–595CrossRefGoogle Scholar
  222. 222.
    Fan XW, Xia CJ, Advincula RC (2003) Intercalation of polymerization initiators into montmorillonite platelets: free radical vs. anionic initiator clays. Colloids Surf A Physicochem Eng Asp 219(1–3):75–86CrossRefGoogle Scholar
  223. 223.
    Uthirakumar P, Nahm KS, Hahn YB, Lee YS (2004) Preparation of polystyrene/ montmorillonite nanocomposites using a new radical initiator- montmorillonite hybrid via in situ intercalative polymerization. Eur Polym J 40(11):2437–2444CrossRefGoogle Scholar
  224. 224.
    Karadag E, Nalbantoglu A, Kundakci S, Uzum OB (2014) Highly swollen polymer/clay composite sorbent-based AAm/AMPS hydrogels and semi-IPNsComposed of Carboxymethyl cellulose and montmorillonite and cross-linked by PEGDA. Polym-Plast Technol Eng 53(1):54–64CrossRefGoogle Scholar
  225. 225.
    Bortolin A, Serafim AR, Aouada FA, Mattoso LHC, Ribeiro C (2016) Macro- and micronutrient simultaneous slow release from highly Swellable nanocomposite hydrogels. J Agric Food Chem 64(16):3133–3140PubMedCrossRefGoogle Scholar
  226. 226.
    Ozkahraman B, Acar I, Emik S (2011) Removal of Cu2+ and Pb2+ ions using CMC based Thermoresponsive nanocomposite hydrogel. Clean: Soil Air Water 39(7):658–664Google Scholar
  227. 227.
    Peng N, Hu DN, Zeng J, Li Y, Liang L, Chang CY (2016) Superabsorbent cellulose-clay nanocomposite hydrogels for highly efficient removal of dye in water. ACS Sustain Chem Eng 4(12):7217–7224CrossRefGoogle Scholar
  228. 228.
    Anirudhan TS, Tharun AR (2012) Preparation and adsorption properties of a novel interpenetrating polymer network (IPN) containing carboxyl groups for basic dye from aqueous media. Chem Eng J 181:761–769CrossRefGoogle Scholar
  229. 229.
    Abu-Jdayil B, Ghannam M (2014) The modification of rheological properties of sodium bentonite-water dispersions with low viscosity CMC polymer effect. Energy Source Part A 36(10):1037–1048CrossRefGoogle Scholar
  230. 230.
    Li JF, Lu JH, Li YM (2009) Carboxylmethylcellulose/bentonite composite gels: water sorption behavior and controlled release of herbicide. J Appl Polym Sci 112(1):261–268CrossRefGoogle Scholar
  231. 231.
    Huang B, Liu MX, Zhou CR (2017) Cellulose-halloysite nanotube composite hydrogels for curcumin delivery. Cellulose 24(7):2861–2875CrossRefGoogle Scholar
  232. 232.
    Del Buffa S, Rinaldi E, Carretti E, Ridi F, Bonini M (2016) Injectable composites via functionalization of 1D nanoclays and biodegradable coupling with a polysaccharide hydrogel. Colloids Surf B: Biointerfaces 145:562–566PubMedCrossRefGoogle Scholar
  233. 233.
    Dai HJ, Huang HH (2017) Enhanced swelling and responsive properties of pineapple peel Carboxymethyl cellulose-g-poly(acrylic acid-co-acrylamide) superabsorbent hydrogel by the introduction of Carclazyte. J Agric Food Chem 65(3):565–574PubMedCrossRefGoogle Scholar
  234. 234.
    Xu J, Meng YZ, Li RKY, Xu Y, Rajulu AV (2003) Preparation and properties of poly(vinyl alcohol)-vermiculite nanocomposites. J Polym Sci B Polym Phys 41(7):749–755CrossRefGoogle Scholar
  235. 235.
    Wang WB, Wang J, Kang YR, Wang AQ (2011) Synthesis, swelling and responsive properties of a new composite hydrogel based on hydroxyethyl cellulose and medicinal stone. Compos Part B Eng 42(4):809–818CrossRefGoogle Scholar
  236. 236.
    AshaRani PV, Mun GLK, Hande MP, Valiyaveettil S (2009) Cytotoxicity and genotoxicity of silver nanoparticles in human cells. ACS Nano 3(2):279–290PubMedCrossRefGoogle Scholar
  237. 237.
    Hebeish A, Hashem M, Abd El-Hady MM, Sharaf S (2013) Development of CMC hydrogels loaded with silver nano-particles for medical applications. Carbohydr Polym 92(1):407–413PubMedCrossRefGoogle Scholar
  238. 238.
    Park MVDZ, Neigh AM, Vermeulen JP, de la LJJ F, Verharen HW, Briede JJ, van Loveren H, de Jong WH (2011) The effect of particle size on the cytotoxicity, inflammation, developmental toxicity and genotoxicity of silver nanoparticles. Biomaterials 32(36):9810–9817PubMedCrossRefGoogle Scholar
  239. 239.
    Mohan YM, Vimala K, Thomas V, Varaprasad K, Sreedhar B, Bajpai SK, Raju KM (2010) Controlling of silver nanoparticles structure by hydrogel networks. J Colloid Interface Sci 342(1):73–82CrossRefGoogle Scholar
  240. 240.
    Rangelova N, Aleksandrov L, Angelova T, Georgieva N, Muller R (2014) Preparation and characterization of SiO2/CMC/ag hybrids with antibacterial properties. Carbohydr Polym 101:1166–1175PubMedCrossRefGoogle Scholar
  241. 241.
    Hebeish AA, El-Rafie MH, Abdel-Mohdy FA, Abdel-Halim ES, Emam HE (2010) Carboxymethyl cellulose for green synthesis and stabilization of silver nanoparticles. Carbohydr Polym 82(3):933–941CrossRefGoogle Scholar
  242. 242.
    Abdel-Halim ES, Alanazi HH, Al-Deyab SS (2015) Utilization of hydroxypropyl carboxymethyl cellulose in synthesis of silver nanoparticles. Int J Biol Macromol 75:467–473PubMedCrossRefGoogle Scholar
  243. 243.
    Goia DV (2004) Preparation and formation mechanisms of uniform metallic particles in homogeneous solutions. J Mater Chem 14(4):451–458CrossRefGoogle Scholar
  244. 244.
    Chen J, Wang J, Zhang X, Jin YL (2008) Microwave-assisted green synthesis of silver nanoparticles by carboxymethyl cellulose sodium and silver nitrate. Mater Chem Phys 108(2–3):421–424CrossRefGoogle Scholar
  245. 245.
    Bozaci E, Akar E, Ozdogan E, Demir A, Altinisik A, Seki Y (2015) Application of carboxymethylcellulose hydrogel based silver nanocomposites on cotton fabrics for antibacterial property. Carbohydr Polym 134:128–135PubMedCrossRefGoogle Scholar
  246. 246.
    Alshehri SM, Aldalbahi A, Al-Hajji AB, Chaudhary AA, Panhuis MIH, Alhokbany N, Ahamad T (2016) Development of carboxymethyl cellulose-based hydrogel and nanosilver composite as antimicrobial agents for UTI pathogens. Carbohydr Polym 138:229–236PubMedCrossRefGoogle Scholar
  247. 247.
    Hebeish A, Sharaf S (2015) Novel nanocomposite hydrogel for wound dressing and other medical applications. RSC Adv 5(125):103036–103046CrossRefGoogle Scholar
  248. 248.
    Gulsonbi M, Parthasarathy S, Raj KB, Jaisankar V (2016) Green synthesis, characterization and drug delivery applications of a novel silver/carboxymethylcellulose - poly(acrylamide) hydrogel nanocomposite. Ecotoxicol Environ Saf 134:421–426PubMedCrossRefGoogle Scholar
  249. 249.
    Wang QY, Cai J, Zhang LN (2014) In situ synthesis of Ag3PO4/cellulose nanocomposites with photocatalytic activities under sunlight. Cellulose 21(5):3371–3382CrossRefGoogle Scholar
  250. 250.
    Nocchetti M, Donnadio A, Ambrogi V, Andreani P, Bastianini M, Pietrella D, Latterini L (2013) Ag/AgCl nanoparticle decorated layered double hydroxides: synthesis, characterization and antimicrobial properties. J Mater Chem B 1(18):2383–2393CrossRefGoogle Scholar
  251. 251.
    Yadollahi M, Namazi H, Aghazadeh M (2015) Antibacterial carboxymethyl cellulose/ag nanocomposite hydrogels cross-linked with layered double hydroxides. Int J Biol Macromol 79:269–277PubMedCrossRefGoogle Scholar
  252. 252.
    Dong H, Snyder JF, Tran DT, Leadore JL (2013) Hydrogel, aerogel and film of cellulose nanofibrils functionalized with silver nanoparticles. Carbohydr Polym 95(2):760–767PubMedCrossRefGoogle Scholar
  253. 253.
    Yang JZ, Liu XL, Huang LY, Sun DP (2013) Antibacterial properties of novel bacterial cellulose nanofiber containing silver nanoparticles. Chin J Chem Eng 21(12):1419–1424CrossRefGoogle Scholar
  254. 254.
    Li Y, Lin ML, Davenport JW (2011) Ab initio studies of cellulose I: crystal structure, intermolecular forces, and interactions with water. J Phys Chem C 115(23):11533–11539CrossRefGoogle Scholar
  255. 255.
    Chen CT, Zhang T, Dai BB, Zhang H, Chen X, Yang JZ, Liu J, Sun DP (2016) Rapid fabrication of composite hydrogel microfibers for Weavable and sustainable antibacterial applications. ACS Sustain Chem Eng 4(12):6534–6542CrossRefGoogle Scholar
  256. 256.
    Pal S, Nisi R, Stoppa M, Licciulli A (2017) Silver-functionalized bacterial cellulose as antibacterial membrane for wound-healing applications. ACS Omega 2:3632–3639PubMedCentralCrossRefPubMedGoogle Scholar
  257. 257.
    Petrov P, Petrova E, Tsvetanov CB (2009) UV-assisted synthesis of super-macroporous polymer hydrogels. Polymer 50(5):1118–1123CrossRefGoogle Scholar
  258. 258.
    Gustaite S, Kazlauske J, Bobokalonov J, Perni S, Dutschk V, Liesiene J, Prokopovich P (2015) Characterization of cellulose based sponges for wound dressings. Colloids Surf A Physicochem Eng Asp 480:336–342CrossRefGoogle Scholar
  259. 259.
    Mekkawy AI, El-Mokhtar MA, Nafady NA, Yousef N, Hamad MA, El-Shanawany SM, Ibrahim EH, Elsabahy M (2017) In vitro and in vivo evaluation of biologically synthesized silver nanoparticles for topical applications: effect of surface coating and loading into hydrogels. Int J Nanomedicine 12:759–777PubMedPubMedCentralCrossRefGoogle Scholar
  260. 260.
    Zhang LL, Ding YL, Povey M, York D (2008) ZnO nanofluids - a potential antibacterial agent. Prog Nat Sci 18(8):939–944CrossRefGoogle Scholar
  261. 261.
    El Shafei A, Abou-Okeil A (2011) ZnO/carboxymethyl chitosan bionano-composite to impart antibacterial and UV protection for cotton fabric. Carbohydr Polym 83(2):920–925CrossRefGoogle Scholar
  262. 262.
    Perelshtein I, Ruderman E, Perkas N, Tzanov T, Beddow J, Joyce E, Mason TJ, Blanes M, Molla K, Patlolla A (2013) Chitosan and chitosan-ZnO-based complex nanoparticles: formation, characterization, and antibacterial activity. J Mater Chem B 1(14):1968–1976CrossRefGoogle Scholar
  263. 263.
    Yadollahi M, Gholamali I, Namazi H, Aghazadeh M (2015) Synthesis and characterization of antibacterial carboxymethyl cellulose/ZnO nanocomposite hydrogels. Int J Biol Macromol 74:136–141PubMedCrossRefGoogle Scholar
  264. 264.
    Fei JQ, Gu LX (2002) PVA/PAA thermo-crosslinking hydrogel fiber: preparation and pH-sensitive properties in electrolyte solution. Eur Polym J 38(8):1653–1658CrossRefGoogle Scholar
  265. 265.
    Hashem M, Sharaf S, Abd El-Hady MM, Hebeish A (2013) Synthesis and characterization of novel carboxymethyl cellulose hydrogels and carboxymethyl cellulolse-hydrogel-ZnO-nanocomposites. Carbohydr Polym 95(1):421–427PubMedCrossRefGoogle Scholar
  266. 266.
    Li XB, Zhang X, Li LC, Huang LL, Zhang W, Ye JD, Hong JG (2016) Preparation of nano-ZnO/regenerated cellulose composite particles via co-gelation and low-temperature hydrothermal synthesis. Mater Lett 175:122–125CrossRefGoogle Scholar
  267. 267.
    Cai J, Zhang L (2006) Unique gelation behavior of cellulose in NaOH/urea aqueous solution. Biomacromolecules 7(1):183–189PubMedCrossRefGoogle Scholar
  268. 268.
    Qin C, Li SJ, Jiang GQ, Jun CB, Guo YL, Li JW, Zhang B, Han SY (2017) Preparation of flower-like ZnO nanoparticles in a cellulose hydrogel microreactor. Bioresources 12(2):3182–3191CrossRefGoogle Scholar
  269. 269.
    Janpetch N, Saito N, Rujiravanit R (2016) Fabrication of bacterial cellulose-ZnO composite via solution plasma process for antibacterial applications. Carbohydr Polym 148:335–344PubMedCrossRefGoogle Scholar
  270. 270.
    Zare-Akbari Z, Farhadnejad H, Furughi-Nia B, Abedin S, Yadollahi M, Khorsand-Ghayeni M (2016) PH-sensitive bionanocomposite hydrogel beads based on carboxymethyl cellulose/ZnO nanoparticle as drug carrier. Int J Biol Macromol 93:1317–1327PubMedCrossRefGoogle Scholar
  271. 271.
    Rakhshaei R, Namazi H (2017) A potential bioactive wound dressing based on carboxymethyl cellulose/ZnO impregnated MCM-41 nanocomposite hydrogel. Mater Sci Eng C Mater Biol Appl 73:456–464PubMedCrossRefGoogle Scholar
  272. 272.
    Ahtzaz S, Nasir M, Shahzadi L, Amir W, Anjum A, Arshad R, Iqbal F, Chaudhry AA, Yar M, Rehman IU (2017) A study on the effect of zinc oxide and zinc peroxide nanoparticles to enhance angiogenesis-pro-angiogenic grafts for tissue regeneration applications. Mater Des 132:409–418CrossRefGoogle Scholar
  273. 273.
    Wan CC, Li J (2016) Graphene oxide/cellulose aerogels nanocomposite: preparation, pyrolysis, and application for electromagnetic interference shielding. Carbohydr Polym 150:172–179PubMedCrossRefGoogle Scholar
  274. 274.
    Xu MM, Huang QB, Wang XH, Sun RC (2015) Highly tough cellulose/graphene composite hydrogels prepared from ionic liquids. Ind Crop Prod 70:56–63CrossRefGoogle Scholar
  275. 275.
    Liu JJ, Chu HJ, Wei HL, Zhu HZ, Wang G, Zhu J, He J (2016) Facile fabrication of carboxymethyl cellulose sodium/graphene oxide hydrogel microparticles for water purification. RSC Adv 6(55):50061–50069CrossRefGoogle Scholar
  276. 276.
    Wang ZM, Ning AM, Xie PH, Gao GQ, Xie LX, Li X, Song AD (2017) Synthesis and swelling behaviors of carboxymethyl cellulose-based superabsorbent resin hybridized with graphene oxide. Carbohydr Polym 157:48–56PubMedCrossRefGoogle Scholar
  277. 277.
    Varaprasad K, Jayaramudu T, Sadiku ER (2017) Removal of dye by carboxymethyl cellulose, acrylamide and graphene oxide via a free radical polymerization process. Carbohydr Polym 164:186–194PubMedCrossRefGoogle Scholar
  278. 278.
    Sung Y, Kim TH, Lee B (2016) Syntheses of carboxymethylcellulose/graphene nanocomposite superabsorbent hydrogels with improved gel properties using electron beam radiation. Macromol Res 24(2):143–151CrossRefGoogle Scholar
  279. 279.
    Chen X, Zhou SK, Zhang LM, You TT, Xu F (2016) Adsorption of heavy metals by graphene oxide/cellulose hydrogel prepared from NaOH/urea aqueous solution. Materials 9(7):582PubMedCentralCrossRefGoogle Scholar
  280. 280.
    Rasoulzadeh M, Namazi H (2017) Carboxymethyl cellulose/graphene oxide bio-nanocomposite hydrogel beads as anticancer drug carrier agent. Carbohydr Polym 168:320–326PubMedCrossRefGoogle Scholar
  281. 281.
    Wang R, Shou D, Lv O, Kong Y, Deng LH, Shen J (2017) pH-controlled drug delivery with hybrid aerogel of chitosan, carboxymethyl cellulose and graphene oxide as the carrier. Int J Biol Macromol 103:248–253PubMedCrossRefGoogle Scholar
  282. 282.
    Zhang HJ, Zhai DD, He Y (2014) Graphene oxide/polyacrylamide/carboxymethyl cellulose sodium nanocomposite hydrogel with enhanced mechanical strength: preparation, characterization and the swelling behavior. RSC Adv 4(84):44600–44609CrossRefGoogle Scholar
  283. 283.
    Liu XY, Zhou YF, Nie WY, Song LY, Chen PP (2015) Fabrication of hydrogel of hydroxypropyl cellulose (HPC) composited with graphene oxide and its application for methylene blue removal. J Mater Sci 50(18):6113–6123CrossRefGoogle Scholar
  284. 284.
    Hao N, Zhang X, Zhou Z, Hua R, Zhang Y, Liu Q, Qian J, Li H, Wang K (2017) AgBr nanoparticles/3D nitrogen-doped graphene hydrogel for fabricating all-solid-state luminol-electrochemiluminescence Escherichia coli aptasensors. Biosens Bioelectron 97:377–383PubMedCrossRefGoogle Scholar
  285. 285.
    Jiang M, Zhang JL, Qiao F, Zhang RY, Xing LB, Zhou J, Cui HY, Zhuo SP (2016) Self-assembled reduced graphene hydrogels by facile chemical reduction using acetaldehyde oxime for electrode materials in supercapacitors. RSC Adv 6(54):48276–48282CrossRefGoogle Scholar
  286. 286.
    Feng YY, Zhang XQ, Shen YT, Yoshino K, Feng W (2012) A mechanically strong, flexible and conductive film based on bacterial cellulose/graphene nanocomposite. Carbohydr Polym 87(1):644–649CrossRefGoogle Scholar
  287. 287.
    Shao W, Wang SX, Liu H, Wu JM, Zhang R, Min HH, Huang M (2016) Preparation of bacterial cellulose/graphene nanosheets composite films with enhanced mechanical performances. Carbohydr Polym 138:166–171PubMedCrossRefGoogle Scholar
  288. 288.
    Ramani D, Sastry TP (2014) Bacterial cellulose-reinforced hydroxyapatite functionalized graphene oxide: a potential osteoinductive composite. Cellulose 21(5):3585–3595CrossRefGoogle Scholar
  289. 289.
    Luo HL, Xiong GY, Yang ZW, Raman SR, Si HJ, Wan YZ (2014) A novel three-dimensional graphene/bacterial cellulose nanocomposite prepared by in situ biosynthesis. RSC Adv 4(28):14369–14372CrossRefGoogle Scholar
  290. 290.
    Si HJ, Luo HL, Xiong GY, Yang ZW, Raman SR, Guo RS, Wan YZ (2014) One-step in situ biosynthesis of graphene oxide-bacterial cellulose nanocomposite hydrogels. Macromol Rapid Commun 35(19):1706–1711PubMedCrossRefGoogle Scholar
  291. 291.
    Luo HL, Ao HY, Li G, Li W, Xiong GY, Zhu Y, Wan YZ (2017) Bacterial cellulose/ graphene oxide nanocomposite as a novel drug delivery system. Curr Appl Phys 17(2):249–254CrossRefGoogle Scholar
  292. 292.
    Wong BS, Yoong SL, Jagusiak A, Panczyk T, Ho HK, Ang WH, Pastorin G (2013) Carbon nanotubes for delivery of small molecule drugs. Adv Drug Deliv Rev 65(15):1964–2015PubMedCrossRefGoogle Scholar
  293. 293.
    Hu Y, Li YZ, Wang D, Zhou WY, Dong XM, Zhou SY, Wang CY, Yang ZH (2017) Highly flexible polymer-carbon dot-ferric ion nanocomposite hydrogels displaying super stretchability, ultrahigh toughness, good self-recovery and shape memory performance. Eur Polym J 95:482–490CrossRefGoogle Scholar
  294. 294.
    Mandal B, Das D, Rameshbabu AP, Dhara S, Pal S (2016) A biodegradable, biocompatible transdermal device derived from carboxymethyl cellulose and multi-walled carbon nanotubes for sustained release of diclofenac sodium. RSC Adv 6(23):19605–19611CrossRefGoogle Scholar
  295. 295.
    Zhang YP, Huang R, Peng S, Ma ZC (2015) MWCNTs/cellulose hydrogels prepared from NaOH/urea aqueous solution with improved mechanical properties. J Chem 2015:1–8Google Scholar
  296. 296.
    Wang M, Anoshkin IV, Nasibulin AG, Ras RHA, Nonappa LJ, Kauppinen EI, Ikkala O (2016) Electrical behaviour of native cellulose nanofibril/carbon nanotube hybrid aerogels under cyclic compression. RSC Adv 6(92):89051–89056PubMedPubMedCentralCrossRefGoogle Scholar
  297. 297.
    Yan ZY, Chen SY, Wang HP, Wang BA, Jiang JM (2008) Biosynthesis of bacterial cellulose/multi-walled carbon nanotubes in agitated culture. Carbohydr Polym 74(3):659–665CrossRefGoogle Scholar
  298. 298.
    Junka K, Guo JQ, Filpponen I, Laine J, Rojas OJ (2014) Modification of cellulose Nanofibrils with luminescent carbon dots. Biomacromolecules 15(3):876–881PubMedCrossRefGoogle Scholar
  299. 299.
    Kim YH, Park S, Won K, Kim HJ, Sang HL (2013) Bacterial cellulose-carbon nanotube composite as a biocompatible electrode for the direct electron transfer of glucose oxidase. J Chem Technol Biotechnol 88(6):1067–1070CrossRefGoogle Scholar
  300. 300.
    Liu SM, Zheng YD, Sun Y, Su L, Yue LN, Wang YS, Feng JX, Fan JS (2016) An oxygen tolerance conductive hydrogel anode membrane for use in a potentially implantable glucose fuel cell. RSC Adv 6(114):112971–112980CrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Pulp & Paper EngineeringSouth China University of TechnologyGuangzhouChina

Personalised recommendations