Antimicrobial activity of green synthesized plasmonic nanoparticles

Abstract Metal nanoparticles have been studied extensively because of their promising applications in areas such as optics, optoelectronics, catalysis, photography, nanostructure fabrication, photonics, and surface-enhanced Raman scattering. Among the known nanoparticles, silver and gold have been widely studied because of their unique optical, electrical, and photothermal properties. The size-dependent silver and gold nanoparticles were synthesized using three natural commonly available plant extracts from Solanum lycopersicums fruit, Hibiscus cannabinus leaf, and Ananas comosus fruit as reducing agents. The optical, structural, vibrational, compositional, and morphological properties of the prepared nanoparticles were studied through ultraviolet (UV)–visible spectra, x-ray powder diffraction, Fourier transform infrared spectroscopy, energy-dispersive x-ray spectroscopy, and high-resolution transmission electron microscopy analysis. The surface plasmon resonance of the prepared nanoparticles was confirmed by UV–visible spectral analysis. The prepared nanoparticles exhibit small spherical shapes. In this chapter, the antibacterial activities of the prepared nanoparticles were done on various pathogenic bacteria like Escherichia coli, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus, and Pseudomonas aeruginosa, which are commonly found in water.