纳米氧化铈的抗氧化生物应用

CeO2是一种常见的催化材料，具有很高的实用及研究价值．人们在其形貌的可控合成以及催化活性的调节等方面进行了大量的研究，取得了很多成果．近年来，随着纳米材料生物应用研究的兴起，纳米氧化铈在生物抗氧化领域的应用受到了越来越多的关注．在纳米尺度下，由于表面氧缺陷的产生，氧化铈中部分cd4＋被还原为Ce3＋以稳定缺陷．此时材料中的Ce3＋和Ce^4＋能够可逆的转化，这一性质使得纳米CeO2能够催化分解生物体内的过量自由基，从而为治疗氧化应激类疾病提供了一种可能．本综述对纳米CeO2的生物抗氧化作用进行了总结，重点讨论了CeO2纳米颗粒的抗氧化机理以及影响其生物效应的关键因素，还介绍了纳米CeO2生物安全性相关的一些研究，并对其生物应用前景进行了展望．

The application of nanoceria in the bio-antioxidation

Ceria is one of the most commonly used catalysts and supports, and has attracted great interests in academic studies and practical applications. There has been a large number of research works on the controllable synthesis and catalytic activity regulation of nanoceria, and lots of achievements have been achieved. In recent years, with the wide use of nanomaterials in the biological areas, much attention has been focused on the bio-antioxidation property of nanoceria. In the nanometer scale, owing to the generation of the surface oxygen defects, some of Ce4＋ ions in the ceria are correspondingly reduced to Ce3＋ to stabilize the defects. In addition, Ce4＋ and Ce3＋ can be transformed reversibly under certain condition. It endows nanoceria with the ability of catalyzing the decomposition of the excess reactive oxygen spices （ROS） in biological tissues. In this review, we summarize the bio-antioxidation property of nanoceria with the emphasis on the antioxidation mechanism and the key influential factors. Besides, a brief introduction to the biosafety assess of the nanoceria and a prospect of its future study are also included.