Highly Porous pH-Responsive Carboxymethyl Chitosan-Grafted-Poly (Acrylic Acid) Based Smart Hydrogels for 5-Fluorouracil Controlled Delivery and Colon Targeting

In the present investigation, new formulations of CMCS/AA hydrogels with varying composition of Carboxymethyl chitosan, acrylic acid, and ethylene glycol dimethacrylate (EGDMA) were prepared by free radical polymerization technique using benzoyl peroxide as catalyst. The bioavailability of 5-FU through the oral route is very limited owing to its rapid metabolism and clearance from the general circulation. Current work was aimed at increasing the bioavailability of 5-FU via smart hydrogels and at investigating their potential in delivering 5-FU to target colon cancer. Swelling studies were carried out on dried hydrogel discs in different USP phosphate buffer solutions of various pH values. Porosity and gel fraction of all the samples were measured. 5-FU was used as a model drug and loaded in selected hydrogel samples. The amount of drug loaded and released was determined. Experimental data was fitted to various model equations, and corresponding parameters were calculated to study the release mechanism. Many structural parameters were calculated. The prepared hydrogels were also characterized by FTIR and SEM to study the structure, crystallinity, compatibility, and morphology of the smart hydrogels. The biocompatibility and cytotoxic potential blank and drug-loaded hydrogels were assessed through MTT assay. The prepared hydrogels were found to be an excellent carrier for 5-FU in targeting colon cancer.