Antiangiogenic evaluation of ZnWO₄ nanoparticles synthesised through microwave-assisted hydrothermal method

Angiogenesis, the complex process of formation of new blood vessels from pre-existing blood vessels, which involves the participation of several pro- and anti-angiogenic factors, is implicated in many physiological and pathological conditions. Nanoparticle-based anti-angiogenic activity at the tumour tissue, harnessed by the Enhanced Permeability and Retention Effect (EPR effect), could potentially become a breakthrough therapy to halt tumour progression. Herein, we evaluate the anti-angiogenic effect of ZnWO₄ nanoparticles (NPs). The nanoparticles were obtained by microwave-assisted hydrothermal synthesis (MAHS) at 120 °C for 60 min and were structurally characterised by X-ray diffraction (XRD) and micro-Raman (MR) spectroscopy. The mean size and polydispersity index were estimated by Zeta potential analysis. The XRD analysis revealed structural organisation at a long-range order, with an average crystallite size of around 3.67 nm, while MR revealed short-range order for ZnWO₄. The anti-angiogenic potential of zinc tungstate nanoparticles was investigated through the chorioallantoic membrane assay (CAM) using fertilised chicken eggs. We demonstrate, in an unprecedented way, that nanocrystalline ZnWO₄ NPs obtained by MAHS, at low reaction temperatures, showed excellent anti-angiogenic properties even at low concentrations. The ZnWO₄ NPs were further evaluated for its cytotoxicity in vitro.