Development of stimuli-responsive chitosan based hydrogels with anticancer efficacy, enhanced antibacterial characteristics, and applications for controlled release of benzocaine

In this work, chitosan and poly(vinylpyrrolidone) based (3-mercaptopropyl)trimethoxysilane (MPTMS) crosslinked hydrogels were prepared for application in drug delivery systems. The swelling behavior in distilled water started to increase until the crosslinker concentration reached the optimum level. The most significant swelling characteristic is noticed in buffer solutions, with higher swelling in an acidic medium and lower swelling in a neutral or basic medium. Morphological studies showed the porous and network structure of specimens, which determines the swelling and release characteristics. Hydrogels manifested antimicrobial characteristics against Listeria monocytogenes (L. monocytogenes) and Salmonella typhimurium (S. typhimurium) bacterial strains. The cell viability against RAW 264.7 cell lines was >90%, and at higher concentrations, the hydrogels showed anti-cancer efficacy against stomach cancerous AGS cell lines. In vitro drug release analysis of benzocaine in phosphate buffer saline (pH 7.4) and simulated intestinal fluid (pH 6.8) showed >90% release within 2 h. These stimuli-responsive hydrogels show enhanced antimicrobial characteristics, biocompatibility, and anti-cancer efficacy, as well as capability of drug release in a controlled manner, which makes them remarkable candidates for use in sustainable drug delivery systems.