K-carrageenan fabricated γ-irradiated graphene oxide hydrogel: A versatile anticancer nanodrug carrier system.

In this study, gamma-irradiated graphene oxide was incorporated into novel pH-responsive hydrogels. The biopolymer kappa carrageenan was blended with polyvinyl alcohol in a silane crosslinked biopolymer, and the effect of gamma irradiation dosage was studied. Nonhazardous tetraethoxysilane (TEOS) was used as a crosslinker. The hydrogels were characterized with chemical and thermal analysis, scanning electron microscopy, and structural analysis using a variety of analytical tools. The swelling behavior of fabricated hydrogels was assessed in various solution media. As the pH of the media increased, the swelling ratio of hydrogels decreased. All fabricated hydrogels had a high swelling ratio at acidic and neutral pH levels, with a decrease in swelling observed at basic pH. The pH-sensitive response at pH 7 make these hydrogels of potential use for controlled injectable-based drug delivery. Hydrogels with the highest swelling percentage were successfully loaded with letrozole (LTZ) to investigate the release mechanism. The drug release test was conducted in PBS and it showed that hydrogel released the LTZ in a regulated manner up to 99% in 4 h. These findings suggest that the hydrogels could serve as intelligent, responsive materials for controlled drug delivery and other biomedical applications at physiological pH.