Green Synthesis of Selenium Nanoparticles by Cyanobacterium <i>Spirulina platensis</i> (abdf2224): Cultivation Condition Quality Controls

Abstract

Selenium nanoparticles (SeNPs) are well-known bioactive compounds. Various chemical and biological methods have been applied to SeNP synthesis. <i>Spirulina platensis</i> is a widely used blue-green microalgae in various industries. In this study, the biosynthesis of SeNPs using sodium selenite and <i>Spirulina platens</i> has been developed. The SeNP synthesis was performed at different cultivation condition including pH and illumination schedule variation. The SeNPs were characterized by FT-IR, XRD, size, and zeta potential measurements, and the antioxidant activities of selected SeNPs were evaluated by DPPH and FRAP assays. FT-IR analysis showed the production of SeNPs. The 12 h dark/12 h light cycles and continuous light exposure at pH 5 led to the production of stable SeNPs with sizes of 145 ± 6 and 171 ± 13 nm, respectively. Antioxidant activity of selected SeNPs was higher than sodium selenite. It seems that green synthesis is a safe method to produce SeNPs as well as a convenient method to scale-up this production.