One-step in situ assembly of size-controlled silver nanoparticles on polyphenol-grafted collagen fiber with enhanced antibacterial properties

Abstract

This paper introduced a facile method for the one-step in situ fabrication of size-controlled AgNPs on collagen fiber (CF) at room-temperature. Epigallocatechin-3-gallate (EGCG), a typical plant polyphenol, was grafted onto the CF surface to serve as a reducing-cum-stabilizing agent, so that the AgNPs were generated on the CF surface without extra chemical reductant or physical treatments. The formation of AgNPs was verified by UV-vis DRS, FT-IR, XRD, XPS, TEM, EDX, and HRTEM measurements. Dispersed AgNPs with small particle size were successfully produced, and the mean particle size of AgNPs could be effectively controlled in the range 22–5 nm simply by varying the grafting degree of EGCG on the CF surface. As-prepared Ag–EGCG–CF materials were subjected to antibacterial assay using Gram-negative bacteria, Escherichia coli (E. coli), as a bacterium model. It was found that Ag–EGCG–CF exhibited excellent antibacterial activity and good durable biocidal utility for repeated use, which was highly dependent on the particle size of AgNPs and the grafting degree of EGCG.