Nanocomposite materials with antimicrobial activity based on chitosan

Abstract

Chitosan nanoparticles (CNP) were prepared by ionic gelation using sodium tripolyphosphate. Metal-enhanced CNP were prepared using the same procedure in the presence of Cu 2+ and Ag+, respectively. The nanoparticulate materials were characterised by FTIR, SEM and antimicrobial assays. The CNP showed higher antimicrobial effect than chitosan against S. saprophyticus and E. coli . The effect did not seem to depend on the molecular weight of the starting chitosan. Cu 2+ and Ag+, both known as antimicrobial agents, showed synergistic effects with chitosan against both organisms. The skin regenerative potential of CNP and metal-enhanced CNP was tested by assessing skin cell (fibroblast, keratinocyte) proliferation. The present study also suggests that chitosan and its nanoparticles inhibits MMP-1 expression in skin fibroblasts and keratinocytes, and may thereby inhibit skin aging and facilitate the ECM remodelling phase of wound healing.