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.

摘要

纳米金刚石 (NDs) 由于其独特的物理化学性质，在纳米技术中具有众多优势。其化学稳定性、天然荧光和高吸收能力使NDs在纳米医学、纳米化妆品和生物医学等许多领域具有应用优势。最近的研究表明，ND 可以清除活性氧（ROS），因此可以作为抗氧化剂。然而，关于 NDs 抗氧化特性的研究有限，它们对过氧化氢 (H ₂ O ₂ ) 诱导的氧化应激的影响尚不清楚。此外，由于纳米医学、纳米化妆品和生物医学产品中 cND 的加入量增加，因此需要进行毒性评估。在这里，我们研究了羧化 ND (cND) 对 H _2的影响O ₂诱导的氧化应激及其在单细胞真核模型酿酒酵母中的 24 小时毒性。我们发现，cND通过降低培养基中的 H ₂ O ₂水平，显着降低了对 H ₂ O ₂诱导的氧化应激反应的细胞死亡和 ROS 积累（ p  < 0.05）。尽管在较高浓度（1000 µg/mL 及以上， p < 0.05）下观察到生长抑制 ，但即使 10.000 µg/mL cND 处理 24 小时也不能完全抑制菌落形成。cND 还显着减少了正常代谢过程中产生的 ROS ( p < 0.05) 并且不会导致细胞死亡。我们的数据表明，cND 显示出 ROS 清除活性，并且在酿酒酵母中没有毒性迹象。