Effect of chemically synthesis compared to biosynthesized ZnO-NPs using Solanum nigrum leaf extract and their photocatalytic, antibacterial and in-vitro antioxidant activity

In the present work, chemically synthesized ZnO-NPs were compared with the biosynthesized ZnO-NPs using aqueous leaf extract of Solanum nigrum (5, 10, 15 and 20 ml), at various concentrations. Different techniques like, UV-vis spectroscopy (UV-vis), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Particle size (DLS), Zeta potential (ZE), High resolution transmission electron microscope (HR-TEM) and Fourier transform infrared spectroscopy (FT-IR) were utilized to characterize the synthesized ZnO-NPs. FT-IR study confirmed the presence of falvonoids and proteins in S. nigrum leaf extract, which were the powerful reducing agents responsible for the reduction of zinc acetate salt. The antibacterial and antioxidant activity of Chem ZnO-NPs and biosynthesized ZnO-NPs were investigated with various Gram positive and Gram negative microbes utilizing disk diffusion technique. The obtained result clearly confirmed the biosynthesized ZnO-NPs potentially played as antimicrobial agent against all tested microorganism and a strong antioxidant activity against DPPH free radical scavenging. Photocatalytic degradation of synthesized ZnO-NPs were also evaluated for methylene blue dye degradation under sunlight irradiation and was confirmed that biosynthesized ZnO-NPs had high degradation compared to Chem ZnO-NPs.