Green synthesis of zinc oxide (ZnO) nanoparticles using aqueous leaf extract of Hardwickia binata : their characterizations and biological applications

The synthesis of ZnO NPs (zinc oxide nanoparticles) from Hardwickia binata leaves extract using zinc acetate NP (nanoparticle) was verified by a colour change and it was assessed using a UV-Vis spectrophotometer at 365 nm. FTIR (Fourier transform infra-red) analysis was done to demonstrate the existence of several functional groups. XRD (X-ray diffraction) findings support to find the structure of ZnO-NPs. SEM (scanning electron microscopy) data confirmed their synthesis ZnO NPs and its shape. Size range of particles was confirmed by using TEM (transmission electron microscopy). Staphylococcus aureus shows high inhibition compared to other bacterial strains. Antioxidant activity shows highest inhibition in DPPH (2, 2-diphenyl-1-picryl-hydrazyl-hydrate) compared to ABTS (2.2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and hydroxyl radical scavenging assay . Anti-inflammatory assay shows highest level of inhibition in HRBC (human red blood cell) membrane stabilization and albumin denaturation. Anti-cancer activity of synthesised ZnO NPs was performed in A431 Human carcinoma cancer cell line and HepG2 liver cancer cell line to evaluate the cytotoxicity of biosynthesized ZnO-NPs. From these findings, it should be noted that synthesised NPs can be utilized for a variety of global biomedical applications in the future.