Structural, vibrational, optical, and anticancer properties of Hyphaene thebaica-reduced nano-lanthanum oxide (La2O3)

Phytoextracts modulated synthesis of nano-scaled spherical lanthanum oxide nanoparticles (La2O3 NPs) are reported using the aqueous extracts of Hyphaene thebaica as a bioreducing and chelating agent. X-ray diffraction (XRD) pattern revealed sharp peaks and single-phase purity. The Debye-Scherrer approximation indicated an average crystallite size of 37 nm, whereas W-H plot revealed a crystallite size of 59 nm, complemented by the high-resolution transmission electron microscopy (HR-TEM). The infrared spectroscopy revealed characteristic La-O band at 426 and 648 cm(-1). K-M function revealed the bandgap of 5.6 eV, whereas broad intense emission peaks between 345 and 750 nm. The Raman spectra revealed peaks at 182, 325, 384, and 491 cm(-1). Elemental composition was confirmed using energy-dispersive X-ray spectroscopy (EDS) spectrum, and the spotty rings from selected area electron diffraction (SAED) indicated the crystalline nature of the HT-La2O3 NPs. In addition, the HT-La2O3 NPs were investigated for in vitro antioxidant, anticancer, antiangiogenic, and cytotoxic potentials. DPPH free radical scavenging activity was highest, that is, 49.54 +/- 0.88% at 1000 mu g/mL. MTT assay on MCF-7 and 3T3 cell lines revealed a median lethal concentration of 114 and 43 mu g/mL, respectively. The antiangiogenic effect examined by chick chorioallantoic membrane (CAM) assay indicated inhibition of 57.14 +/- 0.96% at 1000-mu g/mL concentration with an IC50 of 551 mu g/mL. IC50 for the brine shrimp lethality assay was 314.2 mu g/mL. Our study indicates cytotoxicity of HT-La2O3 NPs, and it further concluded that HT-La2O3 NPs were more potent against 3T3 cells as compared with MCF-7 cells. Further research on the biological synthesis and anticancer studies are recommended for the large-scale applications of the La2O3 NPs.