Enhanced\nAntibacterial Activity of Silver/Polyrhodanine-Composite-Decorated\nSilica Nanoparticles

Abstract

This work describes the synthesis\nof silver/polyrhodanine-composite-decorated\nsilica nanoparticles and their antibacterial activity. Polymerization\nof polyrhodanine proceeded preferentially on the surface of the silica\nnanoparticles where Ag⁺ ions were located. In addition,\nthe embedded Ag⁺ ions were reduced to form metallic Ag\nnanoparticles; consequently, silver/polyrhodanine-composite nanoparticles\n(approximately 7 nm in diameter) were formed on the surface of the\nsilica nanoparticles. The resulting nanostructure was investigated\nusing electron microscopy, Fourier-transform infrared spectroscopy,\nultraviolet–visible spectroscopy, and X-ray photoelectron spectroscopy.\nThe silver/polyrhodanine-nanocomposite-decorated silica nanoparticles\nexhibited excellent antimicrobial activity toward gram-negative Escherichia coli and gram-positive Staphylococcus aureus because of the antibacterial\neffects of the silver nanoparticles and the polyrhodanine. The silver/polyrhodanine-composite\nnanoparticles may therefore have potential for use as a long-term\nantibacterial agent.