Embedded Ag NPs in Cysteine-Poly (acrylic acid) Hydrogel with Antibacterial Activity

Abstract

In this research,Ag NPs were loaded on cysteine modified poly(acrylic acid) (PAA) hydrogel. Obtainedcysteine-hydrogel (Chydrogel) having different functional groups could stabilize Ag NPs better than un-modified hydrogel due to the presence of disulfid bondings. First, obtained PAA hydrogel from radical polymerization was conjugated with cysteine-hydrochloride (Cys) through amidation reaction and then was used as a substrate and stabilization reagent for Ag ions. Ag ions were reduced on Chydrogel in the presence ofNaBH4 as reducing reagent. The resultant nanocomposite was well characterized by using UV–vis, FT-IR, XRD and SEM techniques. Furthermore, the resultant Ag NPs on the surface of Chydrogel showedhigh antibacterial behavior against Gram-negative E. coliand Gram-positive S. aureusdue to the high reaction of thiol-functions with the outer cell surface.