Abstract
A nanocomposite that incorporates cobalt oxide (Co3O4) and nanodiamond (ND) can present both high magnetism (Co3O4) and high hardness (ND). ND particles have potential applications in a variety of fields such as protein immobilization, biosensors, therapeutic molecule delivery and bio-imaging. However, limited information is available in literature on the in-situ synthesis of biocompatible magnetic materials and also on their potential biotoxicity as a result of their entry into environmental compartments and subsequent interaction with biota. In this work, a new kind of bio-compatible magnetic material carboxylated nanodiamond (cND) and Co3O4 was synthesized to obtain the cND-Co3O4 nanocomposite. The synthesis procedure involved in-situ and chemical reduction of cobalt chloride (CoCl2 6H(2)O) and sodium borohydrate (NaBH4). The synthesized cND-Co3O4 nanocomposite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The cyto-genotoxicity of the synthesized nanocomposite material was studied by using onion (Allium cepa L.) as a test model with concentrations of 5, 10 and 20 mu g/ml. The study was also extended to cND and Co3O4 materials for comparison purpose. Co3O4 and cND exhibited their contrasting effects on mitosis and other cyto-genotoxic indices studied herein. This work provided fundamental data on the synthesis and the bio-toxicity of the cND-Co3O4 nanocomposite, which, in turn, can help to expand their multidisciplinary applications. (C) 2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.