Physical and chemical crosslinked microcrystalline cellulose-polyvinyl alcohol hydrogel: freeze-thaw mediated synthesis, characterization and in vitro delivery of 5-fluorouracil

The current work reports the synthesis of microcrystalline cellulose and polyvinyl alcohol co-polymerized crosslinked hydrogels both via physical and chemical crosslinking. While freeze-thawing ensured the physical crosslinking, the crosslinker, ethylene glycol diglycidyl ether ensured the chemical crosslinking. The obtained hydrogels were characterized by Fourier transform infrared spectroscopy, swelling ratio and rheology. The gels showed good equilibrium swelling ratio in deionized (DI) water and phosphate buffer saline (PBS) buffer. The morphological observation revealed porous and glossy nature of hydrogels. The synthesized hydrogels were used as a carrier for 5-Fluorouracil. The in vitro release of drug was performed in PBS buffer (pH = 7.4), leading to a cumulative release of 30-60% from all the chemically crosslinked gels. The kinetic release mechanism suggested the release of drug was mostly due to the controlled Fickian diffusion and swelling of gels. Graphic abstract