Comparative study on temperature/pH sensitive xylan-based hydrogels: their properties and drug controlled release

Temperature/pH dual-responsive hydrogels were prepared by the grafting copolymerization of xylan possessing different functional groups with N-isopropylacrylamide and acrylamide using N, N'-methylenebis-acrylamide as a cross-linker and 2,2-dimethoxy-2-phenylacetophenone as a photoinitiator via ultraviolet irradiation. The influence of xylan and glycidyl methacrylate-modified xylan (GMAX) as the raw materials on the mechanical properties of hydrogels was comparatively investigated. Hydrogels were characterized by SEM, FTIR, TGA and XRD. The prepared hydrogels demonstrated a rapid phase transition temperature around 35 degrees C. The cumulative release rate of acetylsalicylic acid for xylan-based hydrogels and GMAX-based hydrogels reached to 77.5% and 84.2% in the intestinal fluid, respectively. GMAX-based hydrogels had a drug encapsulation efficiency of 95.21% and low drug release rate in gastric fluid. NIH3T3 cells in GMAX-based hydrogels had the high cell viability by MTT essay. Therefore, GMAX-based hydrogels had the good biocompatibility which make them promising in biomedical applications, especially as intestinal-targeted drug carriers.