Green synthesis of silver nanoparticles: characterization and determination of antibacterial potency

Abstract

Silver ions (Ag⁺) and its compounds are highly toxic to microorganisms, exhibiting strong biocidal effects on many species of bacteria but have a low toxicity toward animal cells. In the present study, silver nanoparticles (SNPs) were biosynthesized using aqueous extract of Chlorella vulgaris as reducing agent and size of SNPs synthesized ranged between 15 and 47 nm. SNPs were characterized by UV-visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Fourier infrared spectroscopy, and analyzed for its antibacterial property against human pathogens. This approach of SNPs synthesis involving green chemistry process can be considered for the large-scale production of SNPs and in the development of biomedicines.

Keywords: Biomedicines; Green chemistry; Human pathogens; Silver ions.

Fig. 1

Reaction mixture and UV–visible spectra of the biosynthesized of SNPs

Fig. 2

SEM and TEM micrographs of biosynthesized SNPs

Fig. 3

a Particle size distribution histogram of SNP’s determined from TEM image b SAED showing the characteristic crystal planes of elemental silver

Fig. 4

X-ray diffraction of biosynthesized SNPs

Fig. 5

FTIR of biosynthesized SNPs

Fig. 6

Antimicrobial activity of biosynthesized SNPs