Abstract
The controversy surrounding the transmission of COVID-19 in 2020 has revealed the need to better understand the airborne transmission route of respiratory viruses to establish appropriate strategies to limit their transmission. The effectiveness in protecting against COVID-19 has led to a high demand for face masks. This includes the single-use of non-degradable masks and Filtering Facepiece Respirators by a large proportion of the public, leading to environmental concerns related to waste management. Thus, nanocellulose-based membranes are a promising environmental solution for aerosol filtration due to their biodegradability, renewability, biocompatibility, high specific surface area, non-toxicity, ease of functionalization and worldwide availability. Although the technology for producing high-performance aerosol filter membranes from cellulose-based materials is still in its initial stage, several promising results show the prospects of the use of this kind of materials. This review focuses on the overview of nanocellulose-based filter media, including its processing, desirable characteristics and recent developments regarding filtration, functionalization, biodegradability, and mechanical behavior. The porosity control, surface wettability and surface functional groups resulting from the silylation treatment to improve the filtration capacity of the nanocellulose-based membrane is discussed. Future research trends in this area are planned to develop the air filter media by reinforcing the filter membrane structure of CNF with CNCs. In addition, the integration of sol–gel technology into the production of an air filter can tailor the pore size of the membrane for a viable physical screening solution in future studies.
Graphical abstract
Similar content being viewed by others
Introduction
Protection against airborne pathogens has been a major human health challenge since the emergence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in 2020 (Cheng et al. 2021). The main vector for community transmission of SARS-CoV-2 is respiratory droplets when an infected or asymptomatic patient sneezes, coughs or communicates with others (Konda et al. 2020). As a result, the use of face masks (medical grade or cloth) is becoming ubiquitous worldwide to act as barriers to prevent or limit the transmission of virus-containing droplets from an infected person to others in public spaces (Benson et al. 2021; Cheng et al. 2021). For example, several countries around the world have passed laws mandating the use of medical grade masks or cloth masks in public places and in the workplace to reduce the spread of viruses (Benson et al. 2021). This pandemic makes the face mask a national commodity. Worldwide, 129 billion masks are used each month, which corresponds to about 3 million masks used per minute (Prata et al. 2020; Wang et al. 2022). This growing demand for face masks due to the covid-19 pandemic is resulting in a large amount of waste, estimated at 3.4 million per day, leading to widespread contamination of the environment, (Benson et al. 2021) which can turn into a major wastes management problem (Binda et al. 2021; Fadare and Okoffo 2020). Despite the resulting non-biodegradability and high carbon footprint of petroleum-derived fibres, the filter layer of disposable masks is usually made of a melt-blown polypropylene (PP) nonwoven (Garcia et al. 2006). Furthermore, these synthetic fibre masks could take 450 years to fully decompose, slowly turning into microplastics while having a negative impact on marine life and even entering human food chains (Aragaw 2020; Fadare and Okoffo 2020; Ragusa et al. 2021; Wang et al. 2022). In the context of the crisis caused by the Covid-19 pandemic, nanocellulose-based materials from paper companies and agricultural waste can play a major role in providing a wide variety of cellulose-based products for the general public and healthcare workers (Garcia et al. 2006). This could at the same time limit the risk of shortages of personal protective equipment (PPE) due to the abundance and worldwide availability of cellulose sources.
Several studies have been performed on the development of a novel technology to improve the commercial availability and reduce the environmental concerns of the face mask and FFRs using filter membrane from cellulose-based materials produced via electrospinning technique (Bortolassi et al. 2019; Naragund and Panda 2020; Santos et al. 2020; Wibisono et al. 2020; Xie et al. 2021) and freeze-drying method (Liu et al. 2021a, b; Lu et al. 2018; Sim and Youn 2016; Ukkola et al. 2021; Xiong et al. 2021). Nanocellulose-based filter membranes are potential materials for trapping air pollutants due to their biocompatibility, high specific surface area, renewable nature, biodegradability, worldwide availability and ease of functionalization (Liu et al. 2021a, b; Ukkola et al. 2021). In addition, fibrous filters made of cellulose nanofibrils (CNF) are very effective in removing particulate matter from the air; however, their use remains a challenge due to the lack of studies evaluating moisture resistance treatment, mechanical behaviour as well as filtration performance (Bortolassi et al. 2019). Compared to the conventional non-woven microfibre filter (temporarily charged to allow electrostatic interaction with viruses/bacteria), the cellulose nanofibrils filter is now considered the most effective and durable physical filtering method for protection against air pollutants, due to its small pore size (Givehchi and Tan 2015), but its hydrophilicity and resulting high pressure drop remain a challenge. In addition, the requirement for low airflow resistance (pressure drop < 350 Pa for the N95 respirator) minimises energy consumption and avoids inward leakage of air during breathing, thus eliminating protection against pathogen entry into the airways (Wang et al. 2021). Therefore, significant efforts are needed to develop viable air filtration and purification technologies on nanocellulose-based materials, to tailor the pore size of the filter as well as to modify the functionality of the membrane surface to achieving high hydrophobicity and antibacterial/antiviral resistance.
This study presents a review of potential methods to develop a high performance, moisture resistant, highly breathable and biodegradable nanocellulose (combination of CNF and CNC) air filter membrane to replace the current synthetic non-woven air filter, thereby promoting cleaner production. Information on aerosol transmission of respiratory viruses, with a focus on SARS-CoV-2, will be presented. Then the structure, processing, classification and standard of commercial disposable masks will be discussed. The preparation, functionalization and performance of biodegradable cellulose and nanocellulose filter membranes are highlighted for their potential application in masks and FFRs.
Airborne transmission of respiratory viruses
Due to the high frequency of SARS-CoV-2 spread events in 2020, the controversy surrounding the transmission of COVID-19 has revealed the need to better understand the airborne transmission route of respiratory viruses (Cheng et al. 2021). This helps to establish appropriate strategies to limit the transmission of infections. Therefore, assessing the airborne behaviour of aerosols requires understanding their transmission mechanism. Traditionally, airborne transmission is defined as the inhalation of contagious aerosols smaller than 5 µm and primarily at a distance greater than 1 to 2 m from the patient as shown in Fig. 1 (Wang et al. 2021). Figure 1 shows that several parameters such as environmental factors (temperature, relative humidity, ultraviolet radiation, airflow and ventilation) and physico-chemical properties of aerosols including viral load, physical size, infectivity, pH, electrostatic charge, and air–liquid interfacial properties can affect the transport of virus-laden aerosols. Gravitational forces are applied to droplets (> 100 µm), which typically fall within a few meters of the infected person and are quickly cleared from the air, while aerosols remain airborne longer and can travel much further (Moschovis et al. 2021; Santos et al. 2022). After inhalation, the large virus-laden aerosols (5–100 µm) settle in the upper respiratory tract, while the smaller ones (< 5 µm) settle in both upper respiratory tracts and penetrate deep into the alveolar region of the lungs. The main mode of transmission of the SARS-CoV-2 virus responsible for the spread of COVID-19 has been identified as the inhalation of virus-laden aerosols by the World Health Organization (WHO) and the U.S. Center for Disease Control and Disease Prevention (CDC).
Studies on the particle size distribution of aerosol exhaled during coughing estimate particle sizes ranging from 0.1 to 900 µm, of which about 97% of the measured aerosols are smaller than 1 µm (Zayas et al. 2012). Fabian et al. (2011) demonstrated that an individual infected with the human rhinovirus (HRV) while breathing can exhale up to 7200 aerosol particles per liter of air. As the diameter of SARS-CoV-2 is estimated at 80–150 nm (Essa et al. 2021), an aerosol can potentially contain several virus particles and can remain suspended in the air for several hours. Furthermore, analysis of the spread SARS-CoV-2 shows that it can remain in breath-sized aerosols for more than 16 h while maintaining its structural integrity (Fears et al. 2020).
The first reason for surgical masks in hospitals was to prevent contamination of the wound by surgeons (the wearer) during surgery. Later, with the advent of respiratory infections, they were adopted to protect health care workers from contaminating patients. Leung et al. (2020) evaluated the effectiveness of the surgical mask in preventing contamination from respiratory droplets and aerosols with a particular focus on coronaviruses, influenza viruses and rhinoviruses on volunteers. The results show that the respiratory droplets and aerosols of individuals infected with the coronavirus were 30% and 40% higher, respectively, when the individuals did not use a mask. While wearing the surgical mask eliminates the presence of coronavirus in their respiratory aerosols or droplets (Fig. 2). This experimental method for evaluating the collection efficiency of surgical masks demonstrated the mask's ability to reduce human-to-human coronavirus contamination (World Health Organization 2020a). However, further testing protocols regarding the number of volunteers and the SARS-CoV-2 virus variant would be necessary to adapt the results to the real context.
In addition, the shortage of FFRs and surgical masks during the COVID-19 emergency prompted the researcher to evaluate the filtration capacity of homemade reusable cloth masks. Previous results have shown that the filtration efficiency of these fabric masks can be achieved when several layers and specific combinations of different fabrics are used (Konda et al. 2020). For example, Konda et al. (2020) reported that the combination of fabrics (2–4 layers) including silk, muslin, flannel, cotton and various synthetic fabrics significantly improves filtration efficiency by 5 to 80% (for particle sizes < 300 nm) and 5% to 95% (for particle sizes > 300 nm) compared to a single fabric layer used. Although multi-layer fabric masks are a promising way of capturing particles, special rules must be adopted in their production to ensure filtration efficiency and breathability. Therefore, for the general public, face masks and respirators are used to reduce COVID-19 contamination by acting as a barrier to airborne pollutants, including airborne pathogens.
Performance and environmental impact of disposable masks and respirators
Materials and structure of disposable masks used against airborne transmission
Analysis of droplets emitted during normal human actions such as speech assessed by laser light scattering yields approximately 1000 droplets per second, and these particle emission rates can vary with the speed and intensity of the spoken sounds (Asadi et al. 2019). When wearing a surgical mask, laser light scattering reveals the absence of droplet emissions from the wearer (Bandiera et al. 2020). The mask therefore acts as a barrier to protect the wearer's mouth and nostrils from infected droplets.
Originally, the use of the face mask was to prevent the nose and mouth of the wearer from being exposed to fluids or large airborne droplets, as well as to contain their respiratory secretions (Benson et al. 2021). The unprecedented rapid spread of COVID-19 in 2020 prompted the WHO to recommend the use of PPE, personal hygiene, social distancing and testing to reduce the spread of the virus (World Health Organization 2020a). In communities, wearing a mask is one of the most effective tools for limiting human-to-human contamination. Global demand for face masks due to the COVID-19 pandemic is estimated at 4.3 billion per day and disposable commercial face masks currently use melt-blown polypropylene (PP) non-woven fabric as active layer due to their non-absorbent properties and ability to wick away moisture (Benson et al. 2021; Zhang et al. 2021). To overcome the shortage of surgical masks and FFRs, reusable cloth masks designed by several tailors are commonly used, although there is no scientific evidence of their effectiveness.
Since the beginning of the twentieth century, non-woven fibrous membranes such as polypropylene, sandpaper and, wool felt have been the most explored materials in the manufacture of masks for PPE (Dowd et al. 2020). This is due to the ability to maintain their structural integrity when subjected to high temperatures during autoclaving. The preparation of filter media for respirators and surgical masks is usually done with polypropylene (PP), but some other polymers such as polyethylene (PE), polyethylene terephthalate (PET), polyacrylonitrile (PAN), polylactic acid (PLA) and polyamide (PA) are also often used (Pullangott et al. 2021). Surgical mask manufacturing done with multi-layer non-woven filter media can be prepared via several technologies such as meltblown (M), electrospinning (E), spunbond (S) and their combinations (Fig. 3). The filtration efficiency of a mask regularly depends on the structure and types of non-woven fabrics used in its manufacture and these can vary, depending on the application. For instance, surgical masks are designed to effectively filter particles, such as bacteria larger than 1 micron (Allison et al. 2020). Their structure is made by spunbond–meltblown–spunbond designed to achieve high bacterial filtration efficiency (about 98%), acceptable breathability (differential pressure < 40 Pa/cm2) and hydrophobic surface (Tuñón-Molina et al. 2021; Wibisono et al. 2020). This filtration performance is the result of the combination of different functions of each of the three layers, as illustrated in Fig. 4a: the outer layer imposes hydrophobicity, while the middle and inner layers operate respectively as a filter membrane and an absorbent membrane to trap the virus and droplets emitted by the wearer (Wibisono et al. 2020). The main filter layer of the mask (the middle layer) is manufactured using meltblown technology, which involves the conventional manufacture of micro- or nanofibres from molten polymer extruded through tiny nozzles, blown at high speed (Fig. 4a).
Compared with the structure of surgical masks, the N95 respirator is made of four layers of membranes, as shown in Fig. 4b, but is more complex regarding its structure than a surgical mask (Forouzandeh et al. 2021). The N95 respirator also has a hydrophobic polypropylene (PP) membrane on its outer layer, followed by positively charged cellulose and polyester layers which attract bacteria and viruses via electrostatic interactions (Babaahmadi et al. 2021). Then, the fourth layer (inner layer) is made by spunbond or melt-blown technology (Table 1). Compared to surgical masks, N95 respirators are usually dedicated to healthcare personnel to prevent pathogen infection due to their tight fit, high filtration efficiency, and relatively high cost (Karmacharya et al. 2021). However, during respiration, humidity gradually reduces the effectiveness of the electrically charged filter media (Choi et al. 2021). Thus, according to the WHO, the surgical mask and N95 respirators should be worn for a maximum of 4 h and 8 h, respectively, to avoid self-contamination (World Health Organization 2020b).
The micro-scale of polypropylene fibre used to make respirator and surgical mask filters leads to inappropriate use as a physical screen against aerosolised infectious agents smaller than 300 nm (Choi et al. 2021; Davison 2012). Therefore, a melt-blown filter membrane is subjected to a high energy temporal electric field for electrostatic capacitance. In contrast to the physical sieving mechanism observed on the passive air filter membrane (Fig. 5b), the melt-blown microfibre membrane captures extremely small particles by the adsorption mechanism due to their electrostatic charge, as shown in Fig. 5a. In general, porous membranes are charged by turbocharging, corona charging and in-situ charging techniques to effectively trap particles (Tsai et al. 2002). Additionally, electrostatic air filters have the advantage of maintaining particle removal efficiency and low pressure drop under continuous air flow, when the membrane thickness changes (Chua et al. 2020). However, during human breathing, the moisture emitted reduces the electrostatic surface charge of the filter media, leading to a gradual loss of its adsorption capacity (Choi et al. 2021).
Standards and classification of disposable masks and respirators
Disposable face masks or (FFRs) are subject to various regulatory standards worldwide (Table 2) to control the quality of this kind of material available on the market and to ensure effective health protection for the public or staff. Therefore, in order to claim that your respirator or medical mask meets a certain standard, several physical properties and filtration performance are required (Table 2). According to the National Institute for Occupational Safety and Health (NIOSH) classification, there are three series of face masks, designated by the capital letter N, R or P, according to their resistance to oil, followed by the value of the filtration efficiency in case of exposure to oil-based aerosols, such as glycerine and lubricants (Shanmugam et al. 2021). The letter "N" is for non-oil resistant, "R" for moderately oil resistant and "P" for highly oil resistant. For example, the N95 series refers to a non-oil resistant mask with a filtration efficiency of 95% of airborne particles larger than 300 nm (Forouzandeh et al. 2021). In Europe, masks are labelled FFP2 and FFP3 and can filter up to 94% and 99% of aerosol particles respectively. The equivalent of FFP2 respirators are N95 (USA), P2 (Australia/New Zealand), KN95 (China), DS (Japan) and Korea first Class (Korea) (Zhang et al. 2021). For the protection of hospital staff, the N95 respirator is generally used to achieve a very tight face fit and high filtration efficiency of pathogenic aerosols emitted by infected patients (Tuñón-Molina et al. 2021).
Environmental impact of disposable facemasks
Although disposable masks are a viable solution to reduce the spread of SARS-CoV 2, the management of their wastes is a major environmental problem, as they are made from non-degradable polymeric materials. To date, due to difficulties in sorting and cleaning medical plastics such as surgical masks, their recyclability is limited and they are either subjected to inappropriate incineration or landfilled (Joseph et al. 2021) (Fig. 6a).
These single-use masks, discarded in the environment after use, are transported by rainwater to rivers where they enter the marine environment, adding to the presence of other plastics. Several authors have highlighted in recent years the environmental concern related to surgical masks, made of synthetic materials, as a potential source of microplastic pollution in the ecosystem (DYBAS, 2021; Fadare and Okoffo 2020; Mghili et al. 2022) as illustrated on Fig. 7. In 2020, the marine conservation organisation OceanAsia estimated that 1.56 billion pieces of plastic waste from discarded masks entered the marine environment (DYBAS, 2021). These large quantities of the new type of plastic waste from the mismanagement of discarded masks have a negative impact on marine wildlife and eventually enter human food chains, as they slowly turn into microplastics and can take up to 450 years to break down completely (Aragaw 2020; Fadare and Okoffo 2020). For example, Mghili et al. (2022) studied quantitatively and qualitatively the waste of respiratory masks on five Moroccan beaches during the period from February to June 2021. The results reported the presence of approximately 321 protective masks with a predominance of disposable masks (single-use masks) evaluated at 96.27%. Furthermore, Allison et al. (2020) demonstrated that during the COVID-19 pandemic, if everyone wore a disposable face mask in the UK, contaminated plastic waste per year would increase by up to 66,000 tons. According to Babaahmadi et al. (2021), the global plastic waste resulting from the disposal of synthetic masks should be estimated at 4.1 million tons per year (estimating the weight of a mask at 3 g), of which nearly 80% is disposed of in the marine environment. Another major risk is that these microplastics can pass from the environment to living organisms, including mammals (Ragusa et al. 2021). As evidence, Ragusa et al. (2021) analysed five human placenta samples from consenting pregnant women by Raman Microspectroscopy. The results revealed the presence of 12 microplastic fragments between 5 and 10 microns in size, three of which were identified as PP. In addition, Aragaw, (2020), pointed out that the easy ingestion of masks by organisms such as fish in the aquatic environment can have a significant impact on the food chain and degrade human health. Further research is therefore urgently needed to provide environmentally friendly and biodegradable alternative materials with high filtration performance, while leading to an effective waste management system that can provide a sustainable solution to plastic pollution (Fig. 6b).
Cellulose is the most promising material to partially or completely replace petroleum-based fibers for disposable membrane air filters, for several reasons, including its low cost, abundance, renewability, biodegradability, strong mechanical properties, low density, tunable aspect ratio, and ease of processing and functionalization (Ukkola et al. 2021). Therefore, the development of disposable masks from cellulose-based nanofibres with a filtration capacity comparable to that of N95 respirators and surgical masks may ease the burden of the medical mask shortage and promote cleaner production.
Biodegradable air filter media for facemasks
Due to their multiple advantages, such as corrosion resistance, and adjustable chemical functionality, polymeric materials have been widely used throughout the world, resulting in the production of a large amount of plastic waste, causing serious environmental problems (Aragaw 2020; Hassan et al. 2022; Shanmugam et al. 2021). Environmental concerns generated by the extensive use of biostable (non-degradable) materials have led researchers to turn to biodegradable (hydrolytically and enzymatically degradable) materials such as biopolymers for various applications (Babaahmadi et al. 2021). The degradation process of biopolymers takes place in two steps: enzymatic or hydrolytic cleavage of the sensitive bonds, followed by the complete erosion of the polymer structure (Nair and Laurencin 2007). As a result, biodegradable materials decompose over time, through natural biological processes, into water, non-toxic gases and carbonaceous soil (Leja and Lewandowicz 2010). To date, biodegradable natural polymers have been widely recommended as alternative materials for making packaging films (Li et al. 2020), filtration membranes (Ahne et al. 2019; Liu et al. 2021a; Patil et al. 2021; Ukkola et al. 2021; Xiong et al. 2021), and, in the medical sector (Afshar et al. 2019; Dodero et al. 2020; Venkatesan et al. 2017), for tissue engineering, promoting sustainable solutions. For example, since 2020, with the urgency of the COVID-19 pandemic, several sources of biopolymers, such as cellulose, alginate, poly(lactic acid) (PLA), gelatine, chitosan, chitin, poly(vinyl alcohol) (PVA), polyhydroxyalkanoates (PHA) and their mixtures are frequently used in the manufacture of filter membranes and face masks as viable and sustainable solutions (Essa et al. 2021; Li et al. 2018; Liu et al. 2021a, b; Xie et al. 2021), as shown in Table 3. The fibre diameter, porosity and filtration efficiency of the electrospun filter membrane are the result of the electrospinning (Santos et al. 2019). Liu et al. (Liu et al. 2021a, b) investigated the effect of Ag nanoparticle (AgNP) content and ultrasonication time of poly (ε-caprolactone) (PCL)/zein/Ag nanoparticle (AgNP) mixture on the filtration capacity, biodegradability, mechanical and antimicrobial/antiviral performance of the air filter membrane prepared by ultrasonication followed by electrospinning. The results show that the filter membrane prepared with 1% AgNP and 30 min of ultrasound before the electrospinning process achieved a filtration efficiency of more than 97% for 0.3, 0.5 and 1.0 mm particles, as well as high antiviral and antibacterial efficiencies. In addition, according to Li et al. (2018), the nanoporous PLA/chitosan nanoparticles fibrous membrane prepared by one-step electrospinning with a chitosan:PLA mass ratio of 2.5: 8 achieves high filtration capacity compared to the N95 respirator (98.99% filtration efficiency and pressure drop (147.60 Pa)) and high antibacterial activity of 99.5% and 99.4% against Staphylococcus aureus and Escherichia coli, respectively. This filter membrane achieves 100% of removal efficiency when used in a confined space artificially polluted with cigarettes for 30 min, which may be related to the high specific surface area of the nanofibres and the small through-pore size of the nanofibre membranes. (Ahne et al. 2019) prepared cellulose acetate (CA) filter membranes via an electrospinning process with different CA concentrations (10–30%), deposition time (5–30 min), applied voltage (8–12 kV) and collector distance (10-15 cm) to evaluate the effect of parameters on fibre size. The results show that the filter media deposited for 30 min developed the highest filtration efficiency (about 99.8%), while the highest quality factor (QF) of 0.05 Pa−−1 was obtained from the deposition time of 5 min, voltage of 8 kV, needle tip-collector distance of 12.5 cm and CA concentration of 20%.
Nanocellulose-based filter membrane
Preparation and properties of nanocellulose
Due to its versatility, biodegradability and ability to substitute petroleum-based fibres for nanoporous membranes (Lu et al. 2018), cellulose is a potential material for disposable membrane air filters. Cellulose can be extracted from lignocellulosic biomass and accounts for more than 90% of plant material and 40–45% of wood (Correia et al. 2015; Haldar and Purkait 2020; Garcia et al. 2021; Stanislas et al. 2020). It is embedded in the complex network of hemicellulose and lignin and its fibrous structure plays an essential role in the structural integrity of plant cell walls (Phuong et al. 2022), as shown in Fig. 8.
The macromolecular separation of lignocellulosic compounds is known as the pulping process including delignification which is the breaking of chemical bonds of photolignin (lignin "in situ") due to the solubilisation of the lignin fragments in an organic solvent in the case of the organosolv method or in an alkaline solvent in the case of the soda and kraft methods (Correia et al. 2015). Nanocellulose is a one-dimensional cellulosic material in the nanometer range that is usually prepared from lignocellulosic fibres and can also be extracted from bacteria, algae and tunicates (Garcia et al. 2021). Depending on the expected properties and application, cellulose pulp fibres are subjected to mechanical disintegration to obtain cellulose nanofibres (CNF) or to treatment by acid hydrolysis to obtain cellulose nanocrystals (CNCs), as shown in Fig. 7 and Table 4. Nanocellulose technology gives the filter membrane a high mechanical filtration capacity and the possibility to make them smart materials by their functionalization (Alavi 2019). Unlike nanocellulose filter membranes, cellulose pulp filters form relatively large pores due to their micrometric width, which results in low filtration efficiency against airborne aerosols (Garcia et al. 2021). In addition, the size of the nanocellulose (nanoscale, Table 4) and its high specific surface area (up to 101.8 m2/g) (Jiang and Hsieh 2015) provide a thin filter media with a high porosity (Liu et al. 2021a) and better breathability, as well as an ability to capture and absorb small particles (Chua et al. 2020; Sim and Youn 2016).
Preparation of nanocellulose-based filter membrane
Nanocellulose-based filter media, which could replace petroleum-based masks and respirators (FFP2 or FFP3 for European Standards and N95 or N99 for US standards) in the filtration of airborne viruses, have been intensively developed recently around the world as an environmentally friendly solution (Liu et al. 2021a, b; Ukkola et al. 2021; Wang et al. 2019b). The preparation of cellulose nanofibrils (CNF) from cellulosic materials has several advantages such as high specific surface area, easy functionalization and high mechanical strength (Correia et al. 2016; Stanislas et al. 2022, 2020; Xiong et al. 2021), which improves the capture efficiency of small particles due to the nanoscale of the pores (Ukkola et al. 2021). Recently, CNF have been used to prepare filter media by the freeze-drying method for face masks (Mao et al. 2008; Segetin et al. 2007; Sim and Youn 2016; Ukkola et al. 2021), water decontamination (Sehaqui et al. 2016; Wang et al. 2020), battery separator (Sim et al. 2015), coating layers (Bai et al. 2019), transparent devices (Wang et al. 2020) and vehicle exhaust treatment (Liu et al. 2021a, b), as shown in Table 5. In addition, the cellulose nanofibre filter can be made by mixing it with cellulose pulp (filter pulp/CNF) (Alexandrescu et al. 2016), pulp and PET (filter pulp/PET/CNF) (Sim and Youn 2016), corrugated paper (corrugated filter paper/CNF) (Xiong et al. 2021), and filter paper (FP/CNF filter) (Wang et al. 2019b) for air filtration applications. Despite the hydrophilic character of cellulose-based materials which must be taken into account, all these previous studies strongly recommend their application in active layers of FFRs and masks, acting as a barrier against airborne aerosol contamination (Table 5). That hydrophilic character of nanocellulosic materials is a major problem in relation to their application in face masks, as on contact with moisture, the fibre absorbs water, which could alter the structure and performance of the filter due to the low water resistance and swelling of the fibre (Stanislas et al. 2021a, b; Stanislas et al. 2021a, b). The wet mask can promote the growth of bacteria and fungi, as well as an increase of the risk of virus penetration (Zhou et al. 2020). Therefore, modification of the properties of the cellulose-based filter membrane by hydrophobic and antibacterial treatment is necessary to prevent self-contamination of the face mask user and to maintain the filtration performance and structural integrity of cellulose-based masks.
Functionalization of nanocellulose-based filter membrane
The use of non-woven material to reduce the rapid spread of SARS-CoV-2 through the filtration barrier is a promising solution in the community despite the inability of the mask to kill the viruses, which become an additional source of contamination after disposal (Zhou et al. 2020). However, the integration of the simultaneous properties of hydrophobicity, filtration capacity and antivirus/antibacterial in a mask, particularly in a nanocellulose-based mask, offers a guarantee of effectiveness, long-term use and easy post-treatment. The abundant presence of hydroxyl groups in the cellulose structure offers the possibility of functionalization (Alavi 2019). Carboxyl, amino, sulphate, aldehyde, thiol and phosphate groups are the most commonly used functional groups for the functionalization of cellulose, as shown in Fig. 9. In the case of the nanocellulose-based mask, silylation and cationisation treatments are more appropriate to achieve both high hydrophobicity properties (contact angle with water reaching 154.2°) (Liu et al. 2021a) and permanent ionic charges (Choi et al. 2021) for antiviral performance (Fig. 9).
During filtration, bioaerosols such as fungi, viruses and bacteria usually adhere to the surface of the filter and remain viable, posing a risk of secondary contamination as they can reproduce inside of the filter membrane (Chua et al. 2020). This accumulation of bioaerosols can lead to an increase in filter pressure drop due to clogged pore. Therefore, the development of an air filter with antimicrobial/antiviral properties for face masks is strongly recommended by authors (Choi et al. 2021; Li et al. 2018). Several antimicrobial agents (such as metal and metal oxide nanoparticles, natural products and organometallic structures) have been used by researchers to make respiratory masks with antimicrobial activity, ie., to eliminate viruses or bacteria or fungi in contact with the mask (Zhou et al. 2020), as reported in Table 6.
Furthermore, during the transmission of droplets across the filter membrane, hydrophobicity plays an important role in enhancing the interfacial energy barrier (Aydin et al. 2020), as shown in Fig. 10. When filters are impacted by high velocity droplets, some of them immediately crash through the pores, while another part is transmitted. In general, this process involves energy costs related to shear stresses and interfacial energies that can be influenced by droplet viscosity, filter type and filter porosity (Aydin et al. 2020).
Recently, hydrophobic modification of filter membranes has received considerable attention due to their moisture resistance properties, which can be summarised in two points: firstly, chemical resistance, as well as resistance to water absorption, can be achieved after hydrophobic treatment (Liu et al. 2021a, b) and secondly, hydrophobic treatment allows more water vapour channels to be created through pores, with low surface energy and more reactive binding sites (Zhai et al. 2020). Silane agents (Table 5), such as hexadecyltrimethoxysilane (HDTMS) and methyltrimethoxysilane (MTMS), are commonly used to prepare a CNF filter membrane, improving the hydrophobicity of the nanoporous membrane and promoting the cross-link of CNF (Liu et al. 2021a, b; Ukkola et al. 2021), thereby significantly improving the filtration capacity and mechanical performance of the material. Furthermore, in the preparation of cellulose-based microporous (Lu et al. 2018) and nanoporous (Liu et al. 2021a, b) filters, tert-butyl alcohol (TBA) has proven to be an effective chemical hydrophobic modification technique. The inclusion of TBA in the cellulose fibre suspension promotes the separation of the microfibrils, which results in the formation of a regular spider web-like pore architecture during the freeze-drying process (Ma et al. 2019). This is attributed to the intermolecular bonding created between the TBA molecule and the surface of the microfibrils through hydrogen bonding interactions, which leads to hydrophobic surfaces of the microfibrils by introducing tert-butyl groups (Lu et al. 2018). Therefore, as illustrated in Fig. 11, the self-association behaviour of the microfibrils may be limited by the chemical steric obstruction effect of tert-butyl groups. Figure 11 shows that increasing the TBA content enhances the hindering effect of TBA on ice crystal growth, resulting in the structural transformation of the crystal from a thick to a thin needle-like shape.
Performance of nanocellulose filter membrane
Masks and respirators are primarily used as a barrier for industrially generated particulate matter (PM) (diameter < 10 µm) and contaminated aerosols, such as the new SARS-CoV 2 virus (diameter between 80–150 nm), while maintaining acceptable breathability (pressure drop < 350 Pa for N95 respirator), mechanical properties and moisture resistance (Tuñón-Molina et al. 2021). Due to the shortage of commercial disposable masks and respirators during the COVID-19 pandemic and their non-biodegradability, several researchers attempted to use nanotechnology (Table 5) to design an alternative nanoporous membrane from available biodegradable materials to meet the demand. The results show that cellulose-based materials (cellulose pulp, NFC and CNC) (Table 7) are a promising source of air filter membranes produced by electrospinning or freeze-drying, although the challenge remains to develop a uniform pore size, while maintaining a relatively low pressure drop and high moisture resistance. A significant improvement in the mechanical properties of the polymer-based electrospun membrane by introducing CNCs has been reported in previous studies (El Miri et al. 2015; Santos et al. 2022; Peresin et al. 2010; Zhang et al. 2019). For instance, Santos et al. (2022) demonstrated that the inclusion of CNCs as a reinforcing agents in the production of electrospun PAN/CNCs aerosol filter membranes significantly improves mechanical strength (tensile strength and elastic modulus) and filtration performance, compared to pristine PAN membrane. By replacing the PAN polymer with 20 wt. % of CNCs, the filtration performance of the membrane has increased, showing potential of the material to be used as an active filter layer in the manufacture of FFRs. Table 7 shows the comparable performance of the air filter membrane made from cellulose-based materials.
Conclusions and prospects
This study discusses potential methods for preparing a high-performance, moisture-resistant and highly breathable nanocellulose air filter membrane as an environmentally friendly solution. The worldwide availability, renewable nature, adjustable aspect ratio, ease of processing and functionalisation, strong mechanical properties, biodegradability of cellulose justify its growing interest in the production of disposable air filters to replace petroleum-based membranes. The high filtration performance (high filtration efficiency and low pressure drop) of the nanocellulose-based air filter justifies the growing interest of researchers in this material as an alternative solution to the shortage of medical masks for a cleaner solution. However, the challenge of manufacturing biodegradable masks from nanocellulose-based materials lies in the ability to design a filter membrane with a uniform pore size that is relatively smaller than the diameter of the coronavirus (50–200 nm), while retaining their breathability, mechanical properties and resistance to moisture, like commercial disposable masks. The hydrophilic nature of nanocelluloses is a major challenge for their application in air filtration. Therefore, the use of silane coupling agents or tert-butyl alcohol has proven to be effective in improving their moisture resistance. In addition, the antibacterial/viral treatment of the nanocellulose air filter is essential against self-contamination of the mask user as well as clogging of the filter pores when the pathogen attaches to the filter surface. Although the above properties are necessary for the effectiveness of the aerosol protection capability of nanocellulose-based air filters, little research has simultaneously incorporated antibacterial and hydrophobic treatment, as well as evaluated the impact of the porous membrane production process on their mechanical properties.
Furthermore, the production of the filter membrane with a high porosity contributes to the reduction of the mechanical performance of the membrane. Therefore, the insertion of cellulose nanocrystals (CNCs) into the cellulose nanofibrils (CNF) filter membrane can help maintain the mechanical integrity of the membrane structure while achieving high porosity. In addition, the idea of incorporating sol–gel technology into the production of the cellulose nanofibre filter membrane to tailor the pore size (slightly smaller than the diameter of the viruses/bacteria) could be a viable physical screening solution for future studies.
References
Afshar S, Rashedi S, Nazockdast H, Ghazalian M (2019) Preparation and characterization of electrospun poly(lactic acid)-chitosan core-shell nanofibers with a new solvent system. Int J Biol Macromol 138:1130–1137. https://doi.org/10.1016/j.ijbiomac.2019.07.053
Ahne J, Li Q, Croiset E, Tan Z (2019) Electrospun cellulose acetate nanofibers for airborne nanoparticle filtration. Text Res J 89(15):3137–3149. https://doi.org/10.1177/0040517518807440
Akhtar S, Shahzad K, Mushtaq S, Ali I, Rafe MH, Fazal-ul-Karim SM (2019) Antibacterial and antiviral potential of colloidal Titanium dioxide (TiO2) nanoparticles suitable for biological applications. Mater Res Express 6(10):105409
Alavi M (2019) Modifications of microcrystalline cellulose (MCC), nanofibrillated cellulose (NFC), and nanocrystalline cellulose (NCC) for antimicrobial and wound healing applications. E-Polymers 19(1):103–119
Alexandrescu L, Syverud K, Nicosia A, Santachiara G, Fabrizi A, Belosi F (2016) Airborne nanoparticles filtration by means of cellulose nanofibril based materials. J Biomater Nanobiotechnol 07(01):29–36. https://doi.org/10.4236/jbnb.2016.71004
Al-Hazeem N (2021) Manufacture of fibroustructure facemask to protect against coronavirus using electrospinning. Medico Res Chronicles 8(2):103–110. https://doi.org/10.26838/medrech.2021.8.2.480
Allison AL, Ambrose-Dempster E, Aparsi TD, Bawn M, Casas Arredondo M, Chau C, Chandler K, Dobrijevic D, Hailes H, Lettieri P (2020) The environmental dangers of employing single-use face masks as part of a COVID-19 exit strategy.
Aragaw TA (2020) Surgical face masks as a potential source for microplastic pollution in the COVID-19 scenario. Mar Pollut Bull 159(July):111517. https://doi.org/10.1016/j.marpolbul.2020.111517
Asadi S, Wexler AS, Cappa CD, Barreda S, Bouvier NM, Ristenpart WD (2019) Aerosol emission and superemission during human speech increase with voice loudness. Sci Rep 9:1–10. https://doi.org/10.1038/s41598-019-38808-z
Aydin O, Emon B, Cheng S, Hong L, Chamorro LP (2020) Performance of fabrics for home-made masks against the spread of COVID-19 through droplets : a quantitative mechanistic study. Extreme Mech Lett 40:100924. https://doi.org/10.1016/j.eml.2020.100924
Babaahmadi V, Amid H, Naeimirad M, Ramakrishna S (2021) Biodegradable andmultifunctional surgical facemasks: A briefreviewon demands during COVID-19 pandemic, recent developments, and future perspectives. Sci Total Environ 798:149233
Bai L, Liu Y, Bossa N, Ding A, Ren N, Li G, Liang H, Wiesner MR (2018) Incorporation of cellulose nanocrystals (CNCs) into the polyamide layer of thin-film composite (TFC) nanofiltration membranes for enhanced separation performance and antifouling properties. Environ Sci Technol 52(19):11178–11187. https://doi.org/10.1021/acs.est.8b04102
Bai L, Liu Y, Ding A, Ren N, Li G, Liang H (2019) Surface coating of UF membranes to improve antifouling properties: a comparison study between cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs). Chemosphere 217:76–84. https://doi.org/10.1016/j.chemosphere.2018.10.219
Bandiera L, Pavar G, Pisetta G, Otomo S, Mangano E, Seckl JR, Digard P, Molinari E, Menolascina F, Viola IM (2020) Face coverings and respiratory tract droplet dispersion. R Soc Open Sci 7(12):201663
Benson NU, Fred-Ahmadu OH, Bassey DE, Atayero AA (2021) COVID-19 pandemic and emerging plastic-based personal protective equipment waste pollution and management in Africa. J Environ Chem Eng 9(3):105222. https://doi.org/10.1016/j.jece.2021.105222
Binda G, Bellasi A, Spanu D, Pozzi A, Cavallo D, Bettinetti R (2021) Evaluating the environmental impacts of personal protective equipment use by the general population during the COVID-19 pandemic: a case study of lombardy (northern Italy). Environ - MDPI 8(4):33. https://doi.org/10.3390/ENVIRONMENTS8040033
Borkow G, Zhou SS, Page T, Gabbay J (2010) A novel anti-influenza copper oxide containing respiratory face mask. PLoS ONE 5(6):e11295
Bortolassi ACC, Nagarajan S, de Araújo Lima B, Guerra VG, Aguiar ML, Huon V, Soussan L, Cornu D, Miele P, Bechelany M (2019) Efficient nanoparticles removal and bactericidal action of electrospun nanofibers membranes for air filtration. Mater Sci Eng C 102(April):718–729. https://doi.org/10.1016/j.msec.2019.04.094
Cheng Y, Ma N, Witt C, Rapp S, Wild PS, Andreae MO, Pöschl U, Su H (2021) Face masks effectively limit the probability of SARS-CoV-2 transmission. Science 372(6549):1339–1343. https://doi.org/10.1126/science.abg6296
Choi S, Jeon H, Jang M, Kim H, Shin G, Koo JM, Lee M, Sung HK, Eom Y, Yang H, Jegal J, Park J, Oh DX, Hwang SY (2021) Biodegradable efficient, and breathable multi-use face mask filter. Advanced Science 8:2003155. https://doi.org/10.1002/advs.202003155
Chua MH, Cheng W, Goh SS, Kong J, Li B, Lim JYC, Mao L, Wang S, Xue K, Yang L, Ye E, Zhang K, Chet W, Cheong D, Tan H, Li Z, Tan BH (2020) Face masks in the new COVID-19 normal: materials, testing, and perspectives. Research. https://doi.org/10.34133/2020/7286735
Correia VDC, Curvelo AADS, Marabezi K, Almeida AEFDZ, Savastano Junior H (2015) Bamboo cellulosic pulp produced by the ethanol/water process for reinforcement applications. Ciência Florestal 25:127–135
Correia VDC, dos Santos V, Sain M, Santos SF, Leão AL, Savastano Junior H (2016) Grinding process for the production of nanofibrillated cellulose based on unbleached and bleached bamboo organosolv pulp. Cellulose 23(5):2971–2987. https://doi.org/10.1007/s10570-016-0996-9
Davison AM (2012) Pathogen inactivation and filtration efficacy of a new anti-microbial and anti-viral surgical facemask and N95 against dentistry-associated microorganisms. Int Dentistry Australasian Edition 7(1):36–42
de Amorim JDP, de Souza KC, Duarte CR, da Silva Duarte I, de AssisSalesRibeiro F, Silva GS, de Farias PMA, Stingl A, Costa AFS, Vinhas GM, Sarubbo LA (2020) Plant and bacterial nanocellulose: production, properties and applications in medicine, food, cosmetics, electronics and engineering A review. Environ Chem Lett 18(3):851–869. https://doi.org/10.1007/s10311-020-00989-9
de Santos RPO, Ramos LA, Frollini E (2019) Cellulose and/or lignin in fiber-aligned electrospun PET mats: the influence on materials end-properties. Cellulose 26(1):617–630. https://doi.org/10.1007/s10570-018-02234-7
de Santos RPO, Hao J, Frollini E, SavastanoJunior H, Rutledge GC (2022) Aerosol filtration performance of electrospun membranes comprising polyacrylonitrile and cellulose nanocrystals. J Membr Sci 650(225):120392. https://doi.org/10.1016/j.memsci.2022.120392
Dodero A, Scarfi S, Pozzolini M, Vicini S, Alloisio M, Castellano M (2020) Alginate-based electrospun membranes containing zno nanoparticles as potential wound healing patches: biological, mechanical, and physicochemical characterization. ACS Appl Mater Interfaces 12(3):3371–3381. https://doi.org/10.1021/acsami.9b17597
Dowd KO, Nair KM, Forouzandeh P, Mathew S, Grant J, Moran R, Bartlett J, Bird J, Pillai SC (2020) Face masks and respirators in the fight against the covid-19 pandemic : a review of current materials. Adv Future Perspectives 15:3363
Dybas C (2021) Surgical masks on the beach. Oceanography 34(1):12–14
El Miri N, Abdelouahdi K, Zahouily M, Fihri A, Barakat A, Solhy A, El Achaby M (2015) Bio-nanocomposite films based on cellulose nanocrystals filled polyvinyl alcohol/chitosan polymer blend. J Appl Polym Sci 132(22):1–13. https://doi.org/10.1002/app.42004
Essa WK, Yasin SA, Saeed IA, Ali GAM (2021) Nanofiber-based face masks and respirators as COVID-19 protection: a review. Membranes 11(4):1–14. https://doi.org/10.3390/membranes11040250
Fabian P, Brain J, Houseman EA, Gern J, Milton DK (2011) Origin of exhaled breath particles from healthy and human rhinovirus-infected subjects. J Aerosol Med Pulm Drug Deliv 24(3):137–147
Fadare OO, Okoffo ED (2020) Science of the Total Environment Covid-19 face masks : a potential source of microplastic fi bers in the environment. Sci Total Environ 737:140279. https://doi.org/10.1016/j.scitotenv.2020.140279
Fears AC, Klimstra WB, Duprex P, Weaver SC, Plante JA, Aguilar PV (2020) Persistence of severe acute respiratory syndrome coronavirus 2 in aerosol suspensions. Emerg Infect Dis 26(9):1678–1685
Forouzandeh P, O’Dowd K, Pillai SC (2021) Face masks and respirators in the fight against the COVID-19 pandemic: an overview of the standards and testing methods. Saf Sci 133:104995. https://doi.org/10.1016/j.ssci.2020.104995
French AD (2017) Glucose, not cellobiose, is the repeating unit of cellulose and why that is important. Cellulose 24(11):4605–4609. https://doi.org/10.1007/s10570-017-1450-3
Garcia RA, Cloutier A, Riedl B (2006) Dimensional stability of MDF panels produced from heat-treated fibres. Holzforschung 60(3):278–284. https://doi.org/10.1515/HF.2006.045
Garcia RA, Stevanovic T, Berthier J, Njamen G, Tolnai B, Achim A (2021) Cellulose, nanocellulose, and antimicrobial materials for the manufacture of disposable face masks: a review. Bioresources Com 2(2):4321–4353
Givehchi R, Tan Z (2015) The effect of capillary force on airborne nanoparticle filtration. J Aerosol Sci 83:12–24. https://doi.org/10.1016/j.jaerosci.2015.02.001
Haldar D, Purkait MK (2020) Micro and nanocrystalline cellulose derivatives of lignocellulosic biomass: a review on synthesis, applications and advancements. Carbohydr Polym 250(June):116937. https://doi.org/10.1016/j.carbpol.2020.116937
Hang X, Peng H, Song H, Qi Z, Miao X, Xu W (2015) Antiviral activity of cuprous oxide nanoparticles against Hepatitis C Virus in vitro. J Virol Methods 222:150–157
Hassan IA, Younis A, Al Ghamdi MA, Almazroui M, Basahi JM, El-Sheekh MM, Abouelkhair EK, Haiba NS, Alhussaini MS, Hajjar D, Abdel Wahab MM, El Maghraby DM (2022) Contamination of the marine environment in Egypt and Saudi Arabia with personal protective equipment during COVID-19 pandemic: a short focus. Sci Total Environ 810:152046. https://doi.org/10.1016/j.scitotenv.2021.152046
He H, Gao M, Illés B, Molnar K (2020) 3D Printed and electrospun, transparent, hierarchical polylactic acid mask nanoporous filter. Int J Bioprinting 6(4):1–9. https://doi.org/10.18063/ijb.v6i4.278
Huy TQ, Thanh NTH, Thuy NT, Van Chung P, Hung PN, Le A-T, Hanh NTH (2017) Cytotoxicity and antiviral activity of electrochemical–synthesized silver nanoparticles against poliovirus. J Virol Methods 241:52–57
Jiang F, Hsieh YL (2015) Cellulose nanocrystal isolation from tomato peels and assembled nanofibers. Carbohydr Polym 122:60–68. https://doi.org/10.1016/j.carbpol.2014.12.064
Joseph B, James J, Kalarikkal N, Thomas S (2021) Advanced industrial and engineering polymer research recycling of medical plastics. Adv Industrial Eng Polymer Res 4(3):199–208. https://doi.org/10.1016/j.aiepr.2021.06.003
Karmacharya M, Kumar S, Gulenko O, Cho Y-K (2021) Advances in Facemasks during the COVID-19 Pandemic Era. ACS Appl Bio Mater 4(5):3891–3908. https://doi.org/10.1021/acsabm.0c01329
Kelly EO, Arora A, Pirog S, Ward J, Clarkson PJ (2021) cloth face masks and assessing the accuracy of fit checking. PLoS One 16:1–14. https://doi.org/10.1371/journal.pone.0245688
Konda A, Prakash A, Moss GA, Schmoldt M, Grant GD, Guha S (2020) Aerosol filtration efficiency of common fabrics used in respiratory cloth masks. ACS Nano. https://doi.org/10.1021/acsnano.0c03252
Korsunsky Boris (2019) Summary K093161 actiprotect UF N95 respirator. Phys Teacher 57(5):345–345. https://doi.org/10.1119/1.5098932
Leja K, Lewandowicz G (2010) Polymer biodegradation and biodegradable polymers - A review. Pol J Environ Stud 19(2):255–266
Leung NHL, Chu DKW, Shiu EYC, Chan KH, McDevitt JJ, Hau BJP, Yen HL, Li Y, Ip DKM, Peiris JSM, Seto WH, Leung GM, Milton DK, Cowling BJ (2020) Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med 26(5):676–680. https://doi.org/10.1038/s41591-020-0843-2
Li H, Wang Z, Zhang H, Pan Z (2018) Nanoporous PLA/(Chitosan Nanoparticle) composite fibrous membranes with excellent air filtration and antibacterial performance. Polymers 10(10):10–12. https://doi.org/10.3390/polym10101085
Li S, Ma Y, Ji T, Sameen DE, Ahmed S, Qin W, Dai J, Li S, Liu Y (2020) Cassava starch/carboxymethylcellulose edible films embedded with lactic acid bacteria to extend the shelf life of banana. Carbohydr Polym 248:116805. https://doi.org/10.1016/j.carbpol.2020.116805
Liao M, Liu H, Wang X, Hu X, Huang Y, Liu X, Brenan K, Mecha J, Nirmalan M, Lu JR (2021) ScienceDirect A technical review of face mask wearing in preventing respiratory COVID-19 transmission. Curr Opin Colloid Interface Sci 52:101417. https://doi.org/10.1016/j.cocis.2021.101417
Limited IT (2019) 510(k) Summary K192105 Innonix Antiviral Child Mask.
Listyanda RF, Wildan MW, Ilman MN (2020) Preparation and characterization of cellulose nanocrystal extracted from ramie fibers by sulfuric acid hydrolysis. Heliyon 6(11):e05486. https://doi.org/10.1016/j.heliyon.2020.e05486
Liu T, Cai C, Ma R, Deng Y, Tu L, Fan Y, Lu D (2021a) Super-hydrophobic cellulose nanofiber air filter with highly efficient filtration and humidity resistance. ACS Appl Mater Interfaces 13(20):24032–24041. https://doi.org/10.1021/acsami.1c04258
Liu Y, Li S, Lan W, Hossen A, Qin W (2021b) Electrospun antibacterial and antiviral poly ( ε -caprolactone )/ zein / Ag bead-on-string membranes and its application in air fi ltration. Mater Today Adv 12:100173. https://doi.org/10.1016/j.mtadv.2021.100173
Lu Z, Su Z, Song S, Zhao Y, Ma S, Zhang M (2018) Toward high-performance fibrillated cellulose-based air filter via constructing spider-web-like structure with the aid of TBA during freeze-drying process. Cellulose 25(1):619–629. https://doi.org/10.1007/s10570-017-1561-x
Ma S, Zhang M, Yang B, Song S, Nie J, Lu P (2019) Preparation of cellulosic air filters with controllable pore structures via organic solvent-based freeze casting: the key role of fiber dispersion and pore size. BioResources 13(3):5894–5908. https://doi.org/10.15376/biores.13.3.5894-5908
Mao J, Grgic B, Finlay WH, Kadla JF, Kerekes RJ (2008) Wood pulp based filters for removal of sub-micrometer aerosol particles. Nord Pulp Pap Res J 23(4):420–425. https://doi.org/10.3183/npprj-2008-23-04-p420-425
Melayil KR, Mitra SK (2021) Wetting, adhesion, and droplet impact on face masks. Am Chem Soc. https://doi.org/10.1021/acs.langmuir.0c03556
Meléndez-Villanueva MA, Morán-Santibañez K, Martínez-Sanmiguel JJ, Rangel-López R, Garza-Navarro MA, Rodríguez-Padilla C, Zarate-Triviño DG, Trejo-Ávila LM (2019) Virucidal activity of gold nanoparticles synthesized by green chemistry using garlic extract. Viruses 11(12):1111. https://doi.org/10.3390/v11121111
Mghili B, Analla M, Aksissou M (2022) Face masks related to COVID-19 in the beaches of the moroccan mediterranean: an emerging source of plastic pollution. Mar Pollut Bull 174:113181. https://doi.org/10.1016/j.marpolbul.2021.113181
Mohammed N, Grishkewich N, Tam KC (2018) Cellulose nanomaterials: Promising sustainable nanomaterials for application in water/wastewater treatment processes. Environ Sci Nano 5(3):623–658. https://doi.org/10.1039/c7en01029j
Moschovis PP, Yonker LM, Shah J, Singh D, Demokritou P, Kinane TB (2021) Aerosol transmission of SARS-CoV-2 by children and adults during the COVID-19 pandemic. Pediatr Pulmonol 56(6):1389–1394. https://doi.org/10.1002/ppul.25330
Nair LS, Laurencin CT (2007) Biodegradable polymers as biomaterials. Progress in Polymer Sci (oxford) 32(8–9):762–798. https://doi.org/10.1016/j.progpolymsci.2007.05.017
Naragund VS, Panda PK (2020) Electrospinning of cellulose acetate nanofiber membrane using methyl ethyl ketone and N N-Dimethylacetamide as solvents. Mater Chem Phys 240:122147. https://doi.org/10.1016/j.matchemphys.2019.122147
Pandit P, Maity S, Singha K, Uzun M (2021) Potential biodegradable face mask to counter environmental impact of. Clean Eng Technol 4:100218. https://doi.org/10.1016/j.clet.2021.100218
Patil NA, Gore PM, Jaya Prakash N, Govindaraj P, Yadav R, Verma V, Shanmugarajan D, Patil S, Kore A, Kandasubramanian B (2021) Needleless electrospun phytochemicals encapsulated nanofibre based 3-ply biodegradable mask for combating COVID-19 pandemic. Chem Eng J 416:129152. https://doi.org/10.1016/j.cej.2021.129152
Peresin MS, Habibi Y, Vesterinen AH, Rojas OJ, Pawlak JJ, Seppälä JV (2010) Effect of moisture on electrospun nanofiber composites of poly(vinyl alcohol) and cellulose nanocrystals. Biomacromol 11(9):2471–2477. https://doi.org/10.1021/bm1006689
Phuong HT, Thoa NK, Tuyet PTA, Van QN, Hai YD (2022) Cellulose nanomaterials as a future. Sustain Renew Mater Crystals 12(1):106. https://doi.org/10.3390/cryst12010106
Prata JC, Silva ALP, Walker TR, Duarte AC, Rocha-Santos T (2020) COVID-19 Pandemic Repercussions on the Use and Management of Plastics. Environ Sci Technol 54(13):7760–7765. https://doi.org/10.1021/acs.est.0c02178
Prather KA, Wang CC, Schooley RT (2020) Reducing transmission of SARS-CoV-2. Science 368(6498):1422–1424
Pullangott G, Kannan USG, Kiran DV, Maliyekkal SM (2021) A comprehensive review on antimicrobial face masks: an emerging weapon in fighting pandemics. RSC Adv 11(12):6544–6576. https://doi.org/10.1039/d0ra10009a
Ragusa A, Svelato A, Santacroce C, Catalano P, Notarstefano V, Carnevali O, Papa F, Ciro M, Rongioletti A, Baiocco F, Draghi S, Amore ED, Rinaldo D, Matta M, Giorgini E (2021) Plasticenta : first evidence of microplastics in human placenta. Environ Int 146:106274. https://doi.org/10.1016/j.envint.2020.106274
Richardson healthcare (2022) N95 Particulate Respirator White face mask with head strap. 44(0), 1–10. https://www.richardsonhealthcare.com/n95-particulate-respirator-white-face-mask-head-strap/
Saliu F, Veronelli M, Raguso C, Barana D, Galli P, Lasagni M (2021) The release process of microfibers: from surgical face masks into the marine environment. Environ Adv 4:100042. https://doi.org/10.1016/j.envadv.2021.100042
Santos RPDO, Ramos LA, Frollini E (2020) Bio-based electrospun mats composed of aligned and nonaligned fi bers from cellulose nanocrystals, castor oil, and recycled PET. Int J Biol Macromol 163:878–887. https://doi.org/10.1016/j.ijbiomac.2020.07.064
Segetin M, Jayaraman K, Xu X (2007) Harakeke reinforcement of soil-cement building materials: manufacturability and properties. Build Environ 42(8):3066–3079. https://doi.org/10.1016/j.buildenv.2006.07.033
Sehaqui H, Michen B, Marty E, Schaufelberger L, Zimmermann T (2016) Functional cellulose nanofiber filters with enhanced flux for the removal of humic acid by adsorption. ACS Sustain Chem Eng 4(9):4582–4590. https://doi.org/10.1021/acssuschemeng.6b00698
Sen B, Paul S, Bhowmik KK, Pradhan SN (2020) Development of novel respiratory face masks prepared from banana stem fiber against bio-aerosols: an eco-friendly approach. Lett Appl NanoBioSci 10(1):1993–2002
Shanmugam V, Babu K, Garrison TF, Capezza AJ, Olsson RT, Ramakrishna S, Hedenqvist MS, Singha S, Bartoli M, Giorcelli M (2021) Potential natural polymer-based nanofibres for the development of facemasks in countering viral outbreaks. J Appl Polymer Sci 138:1–19. https://doi.org/10.1002/app.50658
Sim K, Youn HJ (2016) Preparation of porous sheets with high mechanical strength by the addition of cellulose nanofibrils. Cellulose 23(2):1383–1392. https://doi.org/10.1007/s10570-016-0865-6
Sim K, Ryu J, Youn HJ (2015) Structural characteristics of nanofibrillated cellulose mats: effect of preparation conditions. Fibers Polym 16(2):294–301. https://doi.org/10.1007/s12221-015-0294-4
Stanislas TT, Tendo JF, Ojo EB, Ngasoh OF, Onwualu PA, Njeugna E, Savastano Junior H (2020) Production and characterization of pulp and nanofibrillated cellulose from selected tropical plants. J Nat Fibers 00(00):1–17. https://doi.org/10.1080/15440478.2020.1787915
Stanislas TT, Komadja GC, Ngasoh OF, Obianyo II, Tendo JF, Onwualu PA, Savastano Junior H (2021a) Performance and durability of cellulose pulp-reinforced extruded earth-based composites. Arab J Sci Eng. https://doi.org/10.1007/s13369-021-05698-1
Stanislas TT, Tendo JF, Teixeira RS, Ojo EB, Komadja GC, Kadivar M, Savastano Junior H (2021b) Effect of cellulose pulp fibres on the physical, mechanical, and thermal performance of extruded earth-based materials. J Build Eng 39(July):102259. https://doi.org/10.1016/j.jobe.2021.102259
Stanislas TT, Komadja GC, Nafu YR, Mahamat AA, Mejouyo PWH, Tendo JF, Njeugna E, Onwualu PA, Savastano Junior H (2022) Potential of raffia nanofibrillated cellulose as a reinforcement in extruded earth-based materials. Case Stud Constr Mater. https://doi.org/10.1016/j.cscm.2022.e00926
Steward NG, Lau FCN, Kung TW, Lo LY, Ryan DJ, Borstel WV (2018) Composition for use in decreasing the transmission of human pathogens. US Patent 2:1–28
Tavakolian M, Jafari SM, van de Ven TGM (2020) A Review on surface-functionalized cellulosic nanostructures as biocompatible antibacterial materials. Nano-Micro Lett 12(1):1–23. https://doi.org/10.1007/s40820-020-0408-4
Tcharkhtchi A, Abbasnezhad N, Seydani MZ, Zirak N, Farzaneh S, Shirinbayan M (2021) Bioactive Materials An overview of filtration efficiency through the masks: mechanisms of the aerosols penetration. Bioact Mater 6(1):106–122. https://doi.org/10.1016/j.bioactmat.2020.08.002
Toivonen MS, Kaskela A, Rojas OJ, Kauppinen EI, Ikkala O (2015) Ambient-dried cellulose nanofi bril aerogel membranes with high tensile strength and their use for aerosol collection and templates for transparent. Flexible Devices. https://doi.org/10.1002/adfm.201502566
Tsai PP, Schreuder-Gibson H, Gibson P (2002) Different electrostatic methods for making electret filters. J Electrost 54(3–4):333–341
Tuñón-Molina A, Takayama K, Redwan EM, Uversky VN, Andrés J, Serrano-Aroca Á (2021) Protective face masks: current status and future trends. ACS Appl Mater Interfaces 13(48):56725–56751. https://doi.org/10.1021/acsami.1c12227
Ukkola J, Lampim M, Laitinen O, Vainio T, Kangasluoma J, Liimatainen H, Siivola E, Pet T (2021) High-performance and sustainable aerosol filters based on hierarchical and crosslinked nanofoams of cellulose nanofibers. J Clean Product 310:127498. https://doi.org/10.1016/j.jclepro.2021.127498
Venkatesan J, Lee JY, Kang DS, Anil S, Kim SK, Shim MS, Kim DG (2017) Antimicrobial and anticancer activities of porous chitosan-alginate biosynthesized silver nanoparticles. Int J Biol Macromol 98:515–525. https://doi.org/10.1016/j.ijbiomac.2017.01.120
Wang Z, Zhang W, Yu J, Zhang L, Liu L, Zhou X, Huang C, Fan Y (2019) Preparation of nanocellulose / filter paper ( NC / FP ) composite membranes for high-performance filtration. Cellulose 26(2):1183–1194. https://doi.org/10.1007/s10570-018-2121-8
Wang Z, Hao L, Yang F, Wei Q (2020) Mesoporous silica membranes silylated by fluorinated and non-fluorinated alkylsilanes for the separation of methyl tert-butyl ether from water. Membranes 10(4):70. https://doi.org/10.3390/membranes10040070
Wang CC, Prather KA, Sznitman J, Jimenez JL, Lakdawala SS, Tufekci Z, Marr LC (2021) Airborne transmission of respiratory viruses. Science 373:6558. https://doi.org/10.1126/science.abd9149
Wang L, Gao Y, Xiong J, Shao W, Cui C, Sun N, Zhang Y, Chang S, Han P, Liu F, He J (2022) Biodegradable and high-performance multiscale structured nanofiber membrane as mask filter media via poly ( lactic acid ) electrospinning. J Colloid Interface Sci 606:961–970. https://doi.org/10.1016/j.jcis.2021.08.079
Wibisono Y, Fadila CR, Saiful S (2020) Facile Approaches of polymeric face masks reuse and reinforcements for micro-aerosol droplets and viruses filtration : a review. Polymers 12:2516
World Health Organization (2020a) Mask use in the context of COVID-19. December.
World Health Organization (2020b) Rational use of personal protective equipment for COVID-19 and considerations during severe shortages: interim guidance, 23 December 2020b. December, 2. https://www.who.int/publications/i/item/rational-use-of-personal-protective-equipment-for-coronavirus-disease-(covid-19)-and-considerations-during-severe-shortages
Xie X, Zheng Z, Wang X, Lee Kaplan D (2021) Low-density silk nanofibrous aerogels: fabrication and applications in air filtration and oil/water purification. ACS Nano 15(1):1048–1058. https://doi.org/10.1021/acsnano.0c07896
Xiong Z, Lin J, Li X, Bian F, Wang J (2021) Hierarchically structured nanocellulose-implanted air filters for high-e ffi ciency particulate matter removal. ACS Appl Mater Inter. https://doi.org/10.1021/acsami.1c01286
Xu EG, Ren ZJ (2021) Preventing masks from becoming the next plastic problem. Front Environ Sci Eng 15(6):6–8. https://doi.org/10.1007/s11783-021-1413-7
Zayas G, Chiang MC, Wong E, Macdonald F, Lange CF, Senthilselvan A, King M (2012) Cough aerosol in healthy participants : fundamental knowledge to optimize droplet-spread infectious respiratory disease management. BMC Pulmonary Med 12:1–12
Zhai X, Wang X, Zhang J, Yang Z, Sun Y, Li Z, Huang X, Holmes M, Gong Y, Povey M, Shi J, Zou X (2020) Extruded low density polyethylene-curcumin film: a hydrophobic ammonia sensor for intelligent food packaging. Food Packag Shelf Life 26:100595. https://doi.org/10.1016/j.fpsl.2020.100595
Zhang Q, Li Q, Young TM, Harper DP, Wang S (2019) A novel method for fabricating an electrospun polyvinyl alcohol/cellulose nanocrystals composite nanofibrous filter with low air resistance for high-efficiency filtration of particulate matter. ACS Sustain Chem Eng. https://doi.org/10.1021/acssuschemeng.9b00605
Zhang Z, Ji D, He H, Ramakrishna S (2021) Electrospun ultrafine fibers for advanced face masks. Mater Sci Eng R 143:100594. https://doi.org/10.1016/j.mser.2020.100594
Zhou J, Hu Z, Zabihi F, Chen Z, Zhu M (2020) Progress and perspective of antiviral protective material. Adv Fiber Mater 2(3):123–139. https://doi.org/10.1007/s42765-020-00047-7
Acknowledgments
The authors would like to thank the French Ministry of Europe and Foreign Affairs under the "Make Our Planet Great Again (MOPGA 4) Visiting Fellowship Program for Young Researchers", No. mopga-postdoc-4—0855611545 support TIDO TIWA Stanislas. The FAPESP, State of São Paulo Research Foundation, Brazil Process No. 2017/19549-3 also support Rachel Passos de OLIVEIRA SANTOS, for which the authors are grateful. The Brazilian National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnologico) supported Holmer Savastano Junior : {PQ CNPq 307723/2017–8/}, for which the authors are grateful.
Funding
The authors would like to thank the French Ministry of Europe and Foreign Affairs under the "Make Our Planet Great Again (MOPGA 4) Visiting Fellowship Program for Young Researchers", No. mopga-postdoc-4—0855611545 support TIDO TIWA Stanislas. The FAPESP, State of São Paulo Research Foundation, Brazil Process No. 2017/19549–3 also support Rachel Passos de OLIVEIRA SANTOS, for which the authors are grateful. The Brazilian National Council for Scientific and Technological Development (Conselho Nacional de Desenvolvimento Científico e Tecnologico) supported Holmer Savastano Junior: {PQ CNPq 307723/2017–8/}, for which the authors are grateful.
Author information
Authors and Affiliations
Contributions
I declare that all the authors had a significant participation in the development of this work. TTS: Conceptualization, investigation, writing- original draft; KB: Supervision, writing- review & editing, funding acquisition; RPdeOS: Visualization, writing- review & editing; CO-P: Supervision, writing- review & editing, funding acquisition; HSJ: Visualization, writing- review & editing, funding acquisition; M-AA: Conceptualization, supervision, writing- review & editing, funding acquisition.
Corresponding author
Ethics declarations
Conflict of interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Stanislas, T.T., Bilba, K., de Oliveira Santos, R.P. et al. Nanocellulose-based membrane as a potential material for high performance biodegradable aerosol respirators for SARS-CoV-2 prevention: a review. Cellulose 29, 8001–8024 (2022). https://doi.org/10.1007/s10570-022-04792-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10570-022-04792-3