Green synthesis of silver nanoparticles using Macrotyloma uniflorum

Green synthesis of noble metal nanoparticles is a vast developing area of research. In this paper we report the green synthesis of silver nanoparticles using aqueous seed extract of Macrotyloma uniflorum. The effect of experimental parameters such as amount of extract, temperature and pH on the formation of silver nanoparticles was studied. The as prepared samples are characterized using XRD, TEM, UV–Visible and FTIR techniques. The formation of silver nanoparticles is evidenced by the appearance of signatory brown colour of the solution and UV–vis spectra. The XRD analysis shows that the silver nanoparticles are of face centered cubic structure. Well-dispersed silver nanoparticles with anisotropic morphology having size ∼12 nm are seen in TEM images. FTIR spectrum indicates the presence of different functional groups in capping the nanoparticles. The possible mechanism leading to the formation of silver nanoparticles is suggested.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Aqueous extract of horse gram is used as reducing and stabilizing agent. ► The method is independent of seasonal variations. ► TEM images show well-dispersed silver nanoparticles with anisotropic morphology. ► FTIR spectrum shows the involvement of proteins in capping of silver nanoparticles. ► Polyphenols are expected to bring about the reduction of silver ions.