A carboxylated nanodiamond reduces oxidative stress and shows no sign of toxicity in yeast

Abstract

Nanodiamonds (NDs) offer numerous advantages in nanotechnology owing to their unique physicochemical properties. Their chemical stability, natural fluorescence and high absorption capacity make NDs advantageous to be used in many fields including nanomedicine, nano-cosmetics and biomedicine. Recent investigations suggest that NDs can scavenge reactive oxygen species (ROS) therefore act as antioxidants. However, studies regarding the antioxidant properties of NDs are limited and their effects on hydrogen peroxide (H2O2)-induced oxidative stress is not clear. Besides, due to the increased incorporation of cNDs in nanomedical, nano-cosmetics and biomedical products toxicity assessments are needed. Here, we investigated the effects of a carboxylated ND (cND) on H2O2-induced oxidative stress and its 24-hour toxicity in a unicellular eukaryotic model, Saccharomyces cerevisiae. We showed that cND significantly reduces cell death and ROS accumulation in response to H2O2-induced oxidative stress by decreasing H2O2 levels in the media (p < 0.05). Although growth inhibition was observed at higher concentrations (1000 µg/mL and above, p < 0.05), even 10.000 µg/mL cND treatment for 24 hours did not completely inhibit colony formation. cND also significantly reduced ROS generated during normal metabolism (p < 0.05) and did not lead to cell death. Our data suggest that cND shows ROS-scavenging activity and has no sign of toxicity in S. cerevisiae.