Bioactive Ag Immobilized on CaO Coated With Saffron Flower Extract (CaO@Saffron/Ag): A New Nanoparticle for Antibacterial Application and Methylene Blue Dye Degradation

ABSTRACT In this research, nanoparticles (NPs) were prepared by an easy and green method from available and cheap materials (eggshell and saffron flower). The CaO@Saffron/Ag NPs were characterized using common techniques such as the Furrier transform infrared (FT‐IR), X‐ray powder diffraction (XRD), field emission‐scanning electron microscope (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDS), thermogravimetric analysis (TGA), and inductively coupled plasma optical emission spectroscopy (ICP‐OES). The antibacterial activity of CaO@Saffron/Ag NPs and their ability for removal of methylene blue dye from aqueous solution were investigated. CaO@Saffron/Ag NPs showed maximum inhibition zone about 10 and 8 mm against S . aureus bacteria and E. coli , respectively. Also, the minimum inhibitory concentration (MIC) against S . aureus bacteria and E. coli was found 4 and 128 µg/mL respectively. Furthermore, the evaluation of the adsorption of methylene blue (MB) dye by CaO@Saffron/Ag NPs in aqueous solution was validated by Langmuir isotherm and pseudo‐second‐order adsorption kinetics model. The removal efficiency ( R %) of MB dye through adsorption was 98%.