Exploring the environmental and potential therapeutic applications of Myrtus communis L. assisted synthesized zinc oxide (ZnO) and iron doped zinc oxide (Fe-ZnO) nanoparticles

Abstract

Zinc oxide and Fe doped zinc Oxide nanoparticles were prepared by green biosynthesis route using natural extract of Myrtus communis L as an effective chelating agent. The synthesized nanoparticles were characterized by Ultraviolet visible (UV–Visible), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy dispersive x-ray (EDX), Thermogravimetric analysis (TGA) and X-Ray diffraction (XRD) spectroscopic techniques. Antioxidant assays, free radical scavenging assays and hemolysis assays of the synthesized nanoparticles were also carried out for finding their therapeutic applications. The optical band gaps was calculated to be Eg = 3.4 eV and Eg = 3.2 eV for ZnO and Fe-ZnO nanoparticles respectively. Functional groups present in both NPs were confirmed by FTIR spectroscopy. Average particles size of pure ZnO and Fe doped ZnO nanoparticles was 21 nm and 17 nm respectively calculated from XRD pattern. SEM analysis showed that ZnO nanoparticles are granular size and have irregular spherical morphology while with Fe doping there is dispersion of nanoparticles with less agglomeration as well as regular distribution of ZnO NPs. EDX spectra indicate purification of undoped and Fe-ZnO NPs. TGA results showed that 27.8% and 10.4% weight loss occurred for ZnO and Fe-ZnO respectively at the temperature range of 30–600 °C. Doping with Fe content the photoluminescence (PL) intensity of the visible peaks of ZnO decreased. The degradation of Acid Yellow-3 over ZnO and Fe-ZnO NPs follows first order kinetics. The characterized nanoparticles were used as photo catalyst in the degradation of Acid Yellow-3 dye in aqueous solution under UV light illumination. Effect of different parameters i.e. irradiation time, initial dye concentration, catalyst dosage and temperature was also studied. The maximum degradation of dye at time of 120 min, concentration of 10 ppm, catalyst loading was 0.03 g and temperature was 50 °C. Excellent antioxidant potential was shown by the prepared NPs. Good hemolytic activity was shown by undoped ZnO NPs and good antibacterial activity by doped ZnO nanoparticles.