Memecylon edule leaf extract mediated green synthesis of silver and gold nanoparticles

Abstract

We used an aqueous leaf extract of Memecylon edule (Melastomataceae) to synthesize silver and gold nanoparticles. To our knowledge, this is the first report where M. edule leaf broth was found to be a suitable plant source for the green synthesis of silver and gold nanoparticles. On treatment of aqueous solutions of silver nitrate and chloroauric acid with M. edule leaf extract, stable silver and gold nanoparticles were rapidly formed. The gold nanoparticles were characterized by UV-visible spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDAX) and Fourier transform infra-red spectroscopy (FTIR). The kinetics of reduction of aqueous silver and gold ions during reaction with the M. edule leaf broth were easily analyzed by UV-visible spectroscopy. SEM analysis showed that aqueous gold ions, when exposed to M. edule leaf broth, were reduced and resulted in the biosynthesis of gold nanoparticles in the size range 20–50 nm. TEM analysis of gold nanoparticles showed formation of triangular, circular, and hexagonal shapes in the size range 10–45 nm. The resulting silver nanoparticles were predominantly square with uniform size range 50–90 nm. EDAX results confirmed the presence of triangular nanoparticles in the adsorption peak of 2.30 keV. Further FTIR analysis was also done to identify the functional groups in silver and gold nanoparticles. The characterized nanoparticles of M. edule have potential for various medical and industrial applications. Saponin presence in aqueous extract of M. edule is responsible for the mass production of silver and gold nanoparticles.

Keywords:

• Memecylon edule
• nanoparticles
• bioreduction
• electron microscopy
• FTIR

Acknowledgements

The authors acknowledge financial support from the SRM University, Kattankulathur. The authors also thank: Dr D Narasiman, Centre for Floristic Research, Department of Botany, Madras Christian College, Chennai, Tamilnadu, India, for the identification of the plant sample; Gopalakrishnan, Department of Nanotechnology, SRM University, Kattankulathur; Dr KS Lakshmi, SRM College of Pharmacy, SRM University, Kattankulathur, for providing the laboratory facilities for UV-visible spectroscopy and FTIR analysis; K Manikandan, SRM College of Pharmacy, SRM University, Kattankulathur, for technical support. Ms Elavazhagan acknowledges the fellowship from SRM University, Kattankulathur, and is also thankful to the Department of Biotechnology, School of Bioengineering, SRM University, Kattankulathur, for financial support and providing the necessary infrastructure to carry out this work.

Disclosure

The authors declare no conflicts of interest in this work.