Characterization of green synthesized selenium nanoparticles (SeNPs) in two different indigenous halophilic bacteria

Background In the biological method, using nonpathogenic and extremophile bacteria systems are not only safe and highly efficient but also a trump card for synthesizing nanoparticles. Halomonas elongata QW6 IBRC-M 10,214 ( He10214 ) and Salinicoccus iranensis IBRC-M 10,198 ( Si10198 ), indigenous halophilic bacteria, can be used for synthesizing selenium nanoparticles (SeNPs). Methods SeNP biosynthesis was optimized in two halophilic bacteria and characterized by UV–Vis, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD), zeta potential, and energy dispersive X-ray (EDX). Results Optimized conditions for synthesizing SeNPs was at 300 °C at 150 rpm for 72 h and 6 mM or 8 mM concentration of Na 2 SeO 3 . UV–Vis indicated a sharp absorption peak at 294 nm. Spherical-shaped nanoparticles by a diameter of 30–100 nm were observed in FESEM and TEM microscopy images. The produced SeNPs were identified by a peak in FTIR spectra. In XRD analysis, the highest peak diffraction had a relationship with SeNPs. The zeta potential analysis showed SeNP production, and elemental selenium was confirmed by EDX. Conclusions Halophilic bacteria, owing to easy manipulation to create optimization conditions and high resistance, could serve as appropriate organisms for the bioproduction of nanoparticles. The biological method, due to effectiveness, flexibility, biocompatibility, and low cost, could be used for the synthesis of reproducible and stable nanoparticles.