Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, USA.
Environ Sci Technol. 2010 Sep 15;44(18):6954-8. doi: 10.1021/es101821m.
How single-walled carbon nanotubes (SWCNT) function in redox reactions may be related to their behaviors in the induction of oxidative stress. Herein, oxidation of several biologically relevant reducing agents in the presence of SWCNT was studied in aqueous solutions. The selected reductants included a common indicator for intracellular reactive oxygen species (ROS) (2,7-dichlorodihydrofluorescein), small antioxidants (vitamin C, Trolox, and cysteine), and a high-molecular-weight ROS scavenger (bovine serum albumin). The unmodified or carboxylated SWCNT acted as both the oxidants and the catalysts in reactions. Moreover, they accelerated the oxidation reactions mediated by horseradish peroxidase, a representative member of the enzyme family actively involved in balancing oxidative stress. These diverse roles in redox reactions may serve the chemistry basis for SWCNT to induce oxidative stress in biological systems as potential environmental pollutants.
单壁碳纳米管 (SWCNT) 在氧化还原反应中的作用方式可能与其在诱导氧化应激中的行为有关。在此，研究了 SWCNT 存在下几种与生物相关的还原试剂在水溶液中的氧化情况。所选还原剂包括细胞内活性氧（ROS）的常见指示剂（2,7-二氯二氢荧光素）、小分子抗氧化剂（维生素 C、Trolox 和半胱氨酸）以及高分子量 ROS 清除剂（牛血清白蛋白）。未经修饰或羧化的 SWCNT 既充当氧化剂又充当催化剂参与反应。此外，它们还加速了辣根过氧化物酶介导的氧化反应，辣根过氧化物酶是一种积极参与平衡氧化应激的酶家族的代表性成员。SWCNT 在氧化还原反应中的这些不同作用可能为其作为潜在环境污染物在生物系统中诱导氧化应激提供化学基础。
