Effect of the Organic Functionality on the Synthesis and Antimicrobial Activity of Silver Nanoparticles

Abstract

In this paper, the effects of the organic reducing agent and 3-aminopropyltrimethoxysilane on the synthesis and properties of mono-, bi-, and trimetallic noble metal nanoparticles were considered; the antimicrobial activity of these nanomaterials was also evaluated. It was shown that 3-aminoptopyltrimethoxysilane- treated noble metal cations undergo rapid conversion into nanoparticles in the presence of three organic reducing agents, namely, 3-glycidoxypropyltrimethoxysilane (3-GPTMS), cyclohexanone and formaldehyde; the nanoparticles were formed on the order of one minute under microwave incubation. Bimetallic nanoparticles were formed by simultaneous or sequential reduction of metal cations; the formation of trimetallic nanoparticles containing gold, silver and palladium was demonstrated using a similar approach. The nanoparticles were characterized using UV-Visible light spectrophotometry, transmission electron microscopy and zeta potential measurements. All three nanoparticles exhibited a size ≤ 10nm size. The nanoparticles showed antimicrobial activity against Acinetobacter baumannii. Scanning electron microscopy imaging showed an alteration in the size and shape of nanoparticle-treated bacterium, with bleb formation and cell wall disruption observed within 1 h of incubation at the MBC values of the nanoparticles. Fluorescence spectrophotometric imaging of silver nanoparticle-Acinetobacter baumannii interactions suggested selective binding of silver nanoparticles to surface proteins. Our results showed the preparation of the novel silver nanoparticles with potent Anti- Acinetobacter baumannii activity, which can serve as an alternative to conventional antimicrobial agents. © 2025 by World Scientific Publishing Co. Pte. Ltd. All rights reserved.