Green synthesis of lanthanum oxide nanoparticles using Moringa oleifera leaves extract and its biological activities

Abstract

Phytosynthesis is a reliable way to produce metal nanoparticles without affecting the environment. Plant extracts act as reducing agent and favors nanoparticle synthesis. Recently, potential drugs were developed in nanotechnology platforms by the green synthesis approach. In this study, the leaves extract of ‘Moringa Oleifera’ (M. oleifera) used as a reducing agent for the synthesis of Lanthanum oxide nanoparticles (La2O3 NPs). The X-ray diffraction (XRD) confirmed the formation of body-centered cubic structure of La2O3 NPs. The optical behavior of La2O3 NPs was analyzed by UV–Vis spectrum. The bandgap energy of the La2O3 NPs was found to be 4.31 eV using Tauc’s plot. The morphology and purity of La2O3 NPs was analyzed by using Field Emission Scanning Electron Microscope (FESEM) and Energy Dispersive X-ray (EDX) spectrum. High Resolution Transmission Electron Microscope (HR-TEM) analysis reveals the morphology, lattice spacing, and selected area electron diffraction (SAED) pattern of the La2O3 NPs. The XPS analysis of the La2O3 NPs reveals the binding energy of La (3d5/2 and 3d3/2) and O 1s at 835.5, 852.3, and 536 eV respectively. The total antioxidant activity (TOA) of La2O3 NPs was found to be 75.32% at 500 µg/mL with the standard drug of vitamin C. The anti-inflammatory activity of the La2O3NPs was found to be 94.15% at 500 µg/mL using the bovine serum albumin denaturation (BSA) technique. The inhibitory activity of La2O3 NPs against α-amylase was found to be 79.99% at 500 µg/mL. In summary, the pure, highly stable and good biocompatible, greener approach based M. oleifera assisted La2O3 was synthesized for radical scavenging, α-amylase and BSA denaturation inhibition activities which can play a key role in the future biomedical and nano-biotechnological applications.