Semen cassiae extract mediated novel route for the preparation of silver nanoparticles

• Synthesis of silver nanoparticles using semen cassiae extract (SCE) is reported.
• Semen cassiae extract is used as both capping and reducing agents.
• It is the first time to use SCE for synthesis of metallic nanoparticles.
• The small, spherical and well-dispersed particle is observed in the range of 2–30 nm.
• The green method can be extended to other noble metals, such as gold.

In this study, we report a simple and environment friendly method for synthesis of well dispersed and stable silver nanoparticles using semen cassiae extract as both reducing and stabilizing agents in aqueous solution without employing any other reducing and capping agents. The formation of silver nanoparticles was observed by change of color from light yellow to red and the UV–vis absorption spectroscopy. The effect of reaction time and semen cassiae amounts on the synthesis of silver nanoparticles was studied. The morphology of the as prepared silver nanoparticles was examined by using HRTEM, which showed that the silver nanoparticles were spherical in shape with a size distribution from 2 nm to 30 nm. The crystalline structure of the silver nanoparticles was confirmed by XRD analysis. The as synthesized silver nanoparticles were tested against Escherichia coli and the obtained data were indicative of good antibacterial properties of the materials. The method presented in this paper provides a very promising approach to synthesize other noble nanoparticles using renewable materials as reducing and capping agents.