Synthesis of Eco-friendly Cobalt Nanoparticles Using Celosia argentea Plant Extract and Their Efficacy Studies as Antioxidant, Antibacterial, Hemolytic and Catalytical Agent.

The aim of the present study was to synthesize safe and economical cobalt nanoparticles by using secondary metabolites from Celosia argentea plant extract and to further evaluate their antioxidant, antibacterial and hemolytic activities. Catalytic activity of these green synthesized nanoparticles was evaluated for the degradation studies of cationic methylene dye in the presence and absence of anionic surfactant (sodium dodecyl sulfate). Different parameters affecting the dye degradation procedure were investigated and optimized. Fourier transform infrared spectroscopy studies identified the functional groups present in bioactive compounds which were responsible for the reduction and stabilization of the cobalt nanoparticles. The green synthesized cobalt nanoparticles were characterized by X-ray diffraction, scanning electron microscope and energy-dispersive X-ray spectroscopy. Cobalt nanoparticles (CoNPs) exhibited good antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl radical, and its scavenging power was found to be increased with increasing concentration. CoNPs also displayed good antimicrobial activity against tested microbes. Moreover, they showed very less toxicity and efficient activity toward dye degradation. [ABSTRACT FROM AUTHOR]