Combined Used of Rheology and LF-NMR for the Characterization of PVP-Alginates Gels Containing Liposomes
- 157 Downloads
This paper is based on the characterization of the rheological and Low Field NMR (LF-NMR) properties of an interpenetrated hydrogel made up by poly(N-vinyl-2-pyrrolidone) and sodium alginate. The final aim is to use the hydrogel as a delivery matrix for liposomes, widely used tools in the drug delivery field.
Rheology, LF-NMR, TEM, cryo-TEM, confocal laser scanning microscopy and release test were employed to characterize the interpenetrated hydrogel. Different theoretical approaches such as Flory, Chui, Scherer and Schurz theories were used to interpret the experimental results.
We found that the crosslinking mechanisms of the two polymers produced an anti-synergistic effect on the final mechanical properties of the interpenetrated hydrogel. Instead of creating a continuous network, alginate formed isolated, cross-linked, clusters embedded in a continuous network of poly(N-vinyl-2-pyrrolidone). Additionally, gel structure significantly influenced liposome delivery.
The rheological and LF-NMR characterization were confirmed and supported by the independent techniques TEM, cryo-TEM and release tests Thus, our findings reiterate the potentiality of both rheology and LF-NMR for the characterisation of soft materials such as interpenetrated polymeric networks.
Key wordsGel LF-NMR liposomes delivery rheology TEM
Drug delivery system
Dynamic Light Scattering
Frequency sweep test
Low Field Nuclear Magnetic Resonance
Laser Scanning Microscope
- NBD PE
Stress sweep test
Transmission electron microscopy
Acknowledgments and Disclosures
This work was supported by the Italian Ministry of Education (PRIN 2010–11 (20109PLMH2)), by Fondo di Ateneo FRA 2016 – Trieste University, BIOFLUO project, POR FESR 2014–2020, FVG, Italy. The authors would like to acknowledge the Danish National Research Foundation (DNRF122) and Villum Fonden (Grant No. 9301) for Intelligent Drug Delivery and Sensing Using Microcontainers and Nanomechanics (IDUN). Authors would like to acknowledge Prof. Leticia Hosta-Rigau and Dr. Maria Godoy Gallardo for the interesting discussions and the valuable inputs given to the investigation.
- 6.Kuijpers A, van Wachem P, van Luyn MJ, Engbers GH, Krijgsveld J, Zaat SA, et al. In vivo and in vitro release of lysozyme from cross-linked gelatin hydrogels: a model system for the delivery of antibacterial proteins from prosthetic heart valves. J Control Release. 2000;67:323–36.CrossRefPubMedGoogle Scholar
- 17.Marizza P, Abrami M, Keller SS, Posocco P, Laurini E, Goswami K, et al. Synthesis and characterization of UV photocrosslinkable hydrogels with poly(Nvinyl-2-pyrrolidone): determination of the network mesh size distribution. Journal of Polymeric Materials and Polymeric Biomaterials. 2016;65:516–25.CrossRefGoogle Scholar
- 24.Draper NR, Smith H. Applied regression analysis. John Wiley & Sons, Inc., New York, 1966.Google Scholar
- 26.Abrami M, Ascenzioni F, Di Domenico EG, Maschio M, Ventura A, Confalonieri M, Di Gioia S, Conese M, Dapas B, Grassi G, Grassi M. A novel approach based on low field nuclear magnetic resonance for the detection of the pathological components of sputum in cystic fibrosis patients. Magn. Reson. Med. 2018 in press, 22 AUG 2017, DOI: https://doi.org/10.1002/mrm.26876.
- 28.Flory PJ. Principles of polymer chemistry. Ithaca, USA: Cornell University, Press; 1953.Google Scholar
- 30.Schurz J, Rheology of polymer solutions of the network type. Prog Polym Sci, 1991;16:1991, 1–53, 1.Google Scholar