Nanocomposite Hydrogels Based on Poly(vinyl alcohol) and Chitosan with Silver Nanoparticles and Graphene Aimed for Wound Dressing Applications

Abstract

In this work, we prepared hydrogels based on PVA, CHI and Gr, and used them as a porous matrix to synthesize silver nanoparticles by an in situ electrochemical method [3,4]. The hydrogels were prepared from PVA/CHI/Gr colloid dispersions using a simple and effective freezing-thawing method for gelation, without the use of chemical cross linkers. The hydrogels were then swollen in AgNO3 solution to saturate with Ag+ ions and subsequently subjected to constant-voltage electrical current, to reduce silver ions and to obtain AgNPs. This electrochemical method is fast and green, as there is no need for the use of any (potentially toxic) chemical cross linkers and reducing agents, rendering the final product non-toxic and safe for medical applications.