Functional Gold Nanoparticle-Based Antibacterial Agents for Nosocomial and Antibiotic-Resistant Bacteria

Abstract

Medical treatments for bacterial-infections have become challenging because of the emergence of antibiotic-resistant bacterial strains. Thus, new therapeutics and antibiotics must be developed. Arginine and tryptophan can target negatively-charged bacteria and penetrate bacterial cell membrane, respectively. Synthetic-peptides containing arginine, tryptophan and cysteine termini, in other words, (DVFLG)2REEW4C and (DVFLG)2REEW2C, as starting materials were mixed with aqueous tetrachloroauric acid to generate peptide-immobilized gold nanoparticles (i.e., [DVFLG]2REEW4C-AuNPs and [DVFLG]2REEW2C-AuNPs) through one-pot reactions. The peptide immobilized AuNPs exhibit targeting capacity and antibacterial activity. Furthermore, (DVFLG)2REEW4C-AuNPs immobilized with a higher number of tryptophan molecules possess more effective antibacterial capacity than (DVFLG)2REEW2C-AuNPs. Nevertheless, they are not harmful for animal cells. The feasibility of using the peptide-AuNPs to inhibit the cell growth of bacterium-infected macrophages was demonstrated. These results suggested that the proposed antibacterial AuNPs are effective antibacterial agents for Staphylococci, Enterococci and antibiotic-resistant bacterial strains. [Formula: see text].