Nickel doped ZnO nanoparticles decreased dissolution and reduced toxicity in Zebrafish (Danio rerio) embryos

Abstract

Zinc oxide nanoparticle (ZnO NPs) and nickle (Ni) doped ZnO NPs are found to be applied in various kinds dermatological, biomedical and optoelectronic fields. However, available toxicological information is inadequate to assess the potential ecological risk of Ni doped nano-ZnO to aquatic organisms and human. In this study, ZnO NPs and different molar concentrations of Nickle (0–12%) doped ZnO NPs (Ni doped-ZnO NPs) were synthesized and characterized by powder X-ray diffraction, UV–visible diffuse reflectance spectroscopy, field emission scanning electron microscopy (FE-SEM) couple with energy-dispersive x-ray (EDX). Moreover, dissolution of Zn2+ from ZnO NPs was lowered when increasing the Ni doping. To determine toxicity effect of ZnO NPs and Ni doped-ZnO NPs were investigated using zebrafish embryo and larvae by exposing to different concentrations (1, 5, 10, 15, 20, and 25 mg/L). Furthermore, the toxicity of Ni2+ and Zn2+ ions, detached from Ni doped-ZnO NPs were investigated to understand the interrelation between ionic Zn2+ and Ni2+ with the nano-ZnO. The Zn2+ content of chorion was measured as 205 ng/ embryo and 152 ng/ embryo in ZnO NPs (5μg/mL) and 12% Ni doped-ZnO NPs (5μg/mL) respectively. The Zn2+ content of chorion interferes in embryo hatching without directly affecting viability. Our results clearly showed the reduced toxic effects of Ni doped nano-ZnO than ZnO NPs in zebrafish embryos and larvae suggesting that Ni doping could be applicable method to reduce the toxicity of ZnO NPs.