Biogenic Synthesis and Characterization of Selenium Nanoparticles Using the Flower of Bougainvillea spectabilis Willd

The present study reports that the flower of Bougainvillea spectabilis Willd. has the potentiality to reduce sodium selenate and synthesize selenium nanoparticles. The exposure of aqueous sodium selenate to the flower broth of B.spectabilis leads to the synthesis of stable selenium nanoparticles within five days. The colour change of the reaction medium from purple to brown colour indicates the process of reduction. The mechanism of reduction was analyzed through UV-Visible (UV-Vis) Spectrophotometer and the λmax in the Surface Plasmon Resonance (SPR) gradually shifted from 348nm to 326nm over the period of incubation and the absorbance was gradually raised from 0.21 to 1.276 a.u. during the period of reduction. The emission and excitation spectrum showed major peaks at 337.5 and 365.5 nm respectively. Fourier Transform Infra-Red Spectroscopic (FT-IR) analysis substantiated the role of alcohols, amines and ketones in the formation and stabilization of selenium nanoparticles. The X-ray Diffraction (XRD) study confirmed the presence of crystalline selenium nanoparticles with an average size of 53nm. The Energy Dispersive X-ray pattren (EDAX) shows that the synthesized nanoparticles are of selenium. Further the structural view of the synthesized selenium nanoparticles has been documented with the help of Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). The synthesized selenium nanoparticles were hollow and spherical with an average size of 24.24 ± 2.95 nm and found to be stable for more than three months. This biogenic synthesis using the flower of Bougainvillea spectabilis is a cost effective, simple and eco-friendly method.