pH-Responsive Biocompatible Nanocomposite Hydrogels for Therapeutic Drug Delivery

The present study reports the formulations of biocompatible nanocomposite hydrogels using chitosan (CH), poly(vinyl alcohol) (PVA), oleo polyol, and fumed silica (SiO₂) via a free radical polymerization method for anti-cancer drug delivery. Structural, morphological, and mechanical analyses were conducted using FT-IR spectroscopy, scanning electron microscopy, transmission electron microscopy, and rheological techniques. The effect of SiO₂ concentration on mechanical strength, swelling ratios, morphological, and drug delivery behavior was investigated. The incorporation of SiO₂ nanoparticles in hydrogels resulted in a significant enhancement in its properties. MTT assay of human embryonic kidney (HEK-293) and human colon (HCT116) cancer cell lines was conducted for up to 48 h to evaluate biocompatibility and cytotoxicity. These studies confirmed the biocompatible nature of nanocomposite hydrogels. Cisplatin-loaded nanocomposite hydrogels exhibit sustained release as compared to free cisplatin at pH 4.0 and pH 7.4. The in vitro cytotoxicity test of cisplatin-loaded hydrogels using the HCT116 cancer cell line indicates that these hydrogels successfully inhibit the growth of HCT116 cancer cells. The results of in vitro tests for drug loading, sustained release, biodegradability, biocompatibility, and anti-proliferative activity of cisplatin-loaded nanocomposite hydrogels suggest that, in the future, they may find applications in the development of topical (in vivo, in the form of tablets) drug delivery systems.