Evaluation of antioxidant, catalytic and antidiabetic activity of Phaseolus vulgaris (French green bean) mediated nickel oxide and copper doped nickel oxide bimetallic nanoparticles

In this study, nickel oxide nanoparticles (NPs) and copper doped NiO bimetallic nanoparticles (Cu@NiO BMNPs) were synthesized using Phaseolus vulgaris extracts as reducing and stabilizing agents by sol gel methods. The chemical and physical properties of synthesized NiO NPs and Cu@NiO BMNPs were confirmed by various techniques, like UV Visible spectrophotometer (UV-Vis), Fourier transform infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDX), Transmission Electron Microscope (TEM) and X-ray diffraction (XRD) analysis. The optical properties of both NPs observed by UV-Vis analysis with well-defined peak and band gap value 3.2 eV & 2.62 eV. FTIR analysis confirmed the presence of functional group of NPs with fruits extract. The morphology of NPs was confirmed by SEM and TEM analysis as polygonal, rod and spherical shape. The elements present in NPs were confirmed by EDX analysis. The crystalline size calculated based on the XRD analysis was 49.78 nm and 53.66 nm for NiO and Cu@ NiO NPs respectively which were found to be slightly smaller than particle size determined from SEM and TEM micrograph. Antioxidant activity of NPs was examined using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging radicals, Catalytic activities were screened by the degradation of Methylene blue (MB) and by the inhibition of alpha-amylase enzyme, antidiabetic activity of NPs were evaluated using acarbose as standard drug. The Cu@NiO BMNPs showed 77.60 % antioxidant, 76.98 % photocatalytic and 88.86 % antidiabetic activity, which were found to be more as compared to NiO NPs. The NiO and Cu@NiO BMNPs were synthesized for the first-time using P. vulgaris extracts. This study clearly showed that P. vulgaris extracts mediated mono- and bimetallic NPs were more stable and biocompatible than their respective bulk particles.