Quercetin-functionalized gold/silver nanoparticles with tunable antibacterial selectivity for bacterial infection treatment

Abstract

Selective antibacterial use is a key strategy for delaying drug resistance and a principle of precision antibacterial therapy. Developing selective antibacterial agent is highly desired for this purpose. In this study, we developed a green synthesis approach using quercetin as both reducing and stabilizing agent to fabricate quercetin-functionalized gold (QueAuNPs) and silver nanoparticles (QueAgNPs), while achieving precise modulation of their antibacterial activity. Varying the feed ratios during synthesis enabled the production of nanoparticles with tailored antimicrobial potency, i.e., QueAuNPs exhibited Gram-positive antibacterial selectivity, while QueAgNPs demonstrated tunable broad-spectrum or selective Gram-negative antibacterial activity. Meanwhile, quercetin endowed as-prepared nanoparticles with remarkable antioxidant capacity to scavenge reactive oxygen species and alleviate oxidative stress damage. In vitro and in vivo studies confirmed their ability to accelerate wound healing through enhanced cell proliferation and tissue regeneration. This study provides a novel strategy for designing multifunctional nanomaterials with integrated antioxidant, antibacterial, and pro-healing properties, showing promising potential for treating 2 infected and chronic wounds.