Umran Aydemir Sezer

Semi-IPN chitosan/polyvinylpyrrolidone microspheres and films: sustained release and property optimisation.

Abstract A set of chitosan-polyvinylpyrrolidone (CH-PVP) microspheres were prepared as semi-inter penetrating networks (semi-IPN) and loaded with 5-fluorouracil. In vitro release studies showed faster release for semi-IPN microspheres compared to pure CH samples, and the total release was achieved in about 20–30 days, depending on the composition. In vitro cell studies were achieved against human breast adenocarcinoma cell line cells where adsorption of cells on microspheres with a significant decrease in their number was obtained. Meanwhile, the CH-PVP films, which were prepared with the same compositions as in the microspheres, demonstrated an increase in strength from 66 to 118 MPa as the PVP content was decreased. It can be concluded that the prepared CH-PVP semi-IPN microspheres are novel promising carriers compared to pure CH microspheres since it becomes possible to adjust stability and hydrophilicity of the microspheres as well as the release rates of the drugs from the microspheres by changing the ratio of CH/PVP composition.

Cellulose-Based Hydrogels as Biomaterials

Hydrogels are three-dimensional hydrophilic network structures that vary greatly in swelling/shrinkage properties against minor changes such as light density, solvent composition, ionic strength, pH, and temperature. Cellulose-based hydrogels are derived from natural sources which are biodegradable and S. Sezer (*) · Ü. A. Sezer Faculty of Medicine, Department of Pharmacology Medicine, Medical Device and Dermocosmetic Research and Application Laboratory, Süleyman Demirel University, Isparta, Turkey YETEM, Innovative Technologies Research and Application Center, Suleyman Demirel University, Isparta, Turkey e-mail: serdarsezer@sdu.edu.tr İ. Şahin · K. Öztürk · V. Şanko · Z. Koçer Institute of Chemical Technology, TUBITAK Marmara Research Center, Gebze, Kocaeli, Turkey # Springer International Publishing AG, part of Springer Nature 2018 Md. I. H. Mondal (ed.), Cellulose-Based Superabsorbent Hydrogels, Polymers and Polymeric Composites: A Reference Series, https://doi.org/10.1007/978-3-319-76573-0_40-1 1 low-immunologic. These hydrogels are produced in four different ways: those obtained directly from native cellulose (including bacterial cellulose), those derived from cellulose derivatives (methyl cellulose, carboxymethyl cellulose, hydroxy methyl cellulose, etc.), those obtained with other polymers as a composite, and finally those obtained from cellulose-inorganic hybrids. Cellulose hydrogels and its derivatives have many desirable properties such as high water retention capacity, high crystallinity, fine fiber network, easy formability, and high tensile strength. In addition, some cellulose derivatives exhibit intelligent behavior against physiological variables such as pH and ionic strength. Cellulosebased hydrogels have advantages such as better biocompatibility, less latent toxicity, and lower cost than the most synthetic polymer hydrogels. Because of these advantages, cellulose-based hydrogels are preferred to be used in industrial pharmaceutics and biomedical fields. This chapter will discuss applications of cellulose-based hydrogels in pharmaceutical industry and biomedical fields such as drug release systems, wound healing, and tissue engineering. In addition, future prospects on cellulose-based hydrogels will be addressed.