Improved physical, thermal, and biological properties of green synthesized Ag-containing nanocomposites of a novel chitosan-based blend

Abstract

Different material compositions are being prepared to improve the physiochemical properties of chitosan biopolymer and thus to create new areas of use. This study presents new chitosan(CS)-based products based on synthetic polymers and biosynthesized AgNPs, prioritizing environmentally friendly synthesis methods. Methacrylate-based functional CP copolymer was prepared by the free radical polymerization method. Thanks to the amide, ester groups, and fluorine atoms in the side branch of the CP, a compatible polymer blend (CS-CP) was prepared by the environmentally friendly hydrothermal method through hydrogen bonds with CS. Again, with green synthesis applications, AgNPs were prepared from Prunus spinosa extract by hydrothermal method, and new nanocomposites were produced by adding CS-CPs at different weight ratios. The initial decomposition temperature of 245 °C, which indicates the thermal stability of CS-CP as determined by TGA, was increased to 268 °C with the addition of 7 % AgNPs. Adding CP to CS lowered the glass transition temperature, and this trend continued in nanocomposites with the addition of AgNPs. When CP was blended with CS, the oxidative stress index of CS increased from 18.26 AU to 65.45 AU. It was determined that this oxidative effect increased up to 181 AU when AgNPs were added. Thanks to this feature of the produced nanocomposites, it was found that the MIC (100–250 µg/mL for E. coli, 250–500 µg/mL for S. aureus and for 500–1000 µg/mL C. Albicans) values of CS against microorganisms decreased, and the antimicrobial activity increased. In addition, in studies with cancer (A549 and G361) cells, it was determined that even at low (25 µg/mL) doses, nanocomposites that included 5 % and 7 % AgNPs in their formula had anticarcinogenic activity. Further studies on biocompatibility may be recommended to confirm possible commercial benefits from the materials produced in future research.