Crosslinking of gelatin-based drug carriers by genipin induces changes in drug kinetic profiles in vitro

Hydrogels are extensively studied as carrier matrices for the controlled release of bioactive molecules. The aim of this study was to design gelatin-based hydrogels crosslinked with genipin and study the impact of crosslinking temperature (5, 15 or 25°C) on gel strength, microstructure, cytocompatibility, swelling and drug release. Gels crosslinked at 25°C exhibited the highest Flory-Rehner crosslink density, lowest swelling ratio and the slowest release of indomethacin (Idn, model anti-inflammatory drug). Diffusional exponents (n) indicated non-Fickian swelling kinetics while drug transport was anomalous. Hydrogel biocompatibility, in vitro cell viability, cell cycle experiments with AH-927 and HaCaT cell lines indicated normal cell proliferation without any effect on cell cycle. Overall, these results substantiated the use of genipin-crosslinked hydrogels as a viable carrier matrix for drug release applications.