共价功能化对单壁碳纳米管产生DNA损伤和活性氧的影响研究  

Effect of Covalent Functionalization on DNA Cleavage Activity and ROS Formation of Single-Walled Carbon Nanotubes

作　　者：吴仁人[1,2] 陶雪琴[3] 党志[2] 李开明[1] 蔡美芳[1] 

机构地区：[1]环境保护部华南环境科学研究所,广州510655 [2]华南理工大学环境科学与工程学院,广州510006 [3]仲恺农业工程学院环境科学与工程学院,广州510225

出　　处：《环境科学》2012年第9期3241-3246,共6页Environmental Science

基　　金：工业聚集区污染控制与生态修复教育部重点实验室开放基金项目;国家自然科学基金项目(41101299);国家水体污染控制与治理科技重大专项(2009ZX07528-001)

摘　　要：以质粒DNA评价法表征了不同程度共价功能化单壁碳纳米管(SWNTs)的生物毒性,并在近红外-可见光光谱、拉曼光谱和活性氧(ROS)表征的基础上研究了共价功能化对其物理结构和化学活性的影响.结果表明,共价功能化增强了碳纳米管对质粒DNA的损伤程度,3种不同类型的碳纳米管对DNA损伤的强度为羧基功能化SWNTs(SWNT-COOH)>聚乙二醇功能化SWNTs(SWNT-PEG)>非共价功能化SWNTs(uSWNTs).随着共价功能化程度的加深,碳纳米管表面石墨晶格的sp2结构受损程度逐渐增高,以致使其反应活性增大.共价功能化后SWNTs可作为电子转移中间体将NADH中的电子转移至O2并生成ROS从而对DNA造成损伤.Biotoxicity of selected covalent functionalizaed single-walled carbon nanotubes（SWNTs） was investigated by plasmid DNA cleavage assay.The effect of covalent functionalization on the physical structural and chemical activity of SWNTs was also studied by Vis-NIR spectroscopy,Raman spectroscopy and ROS assay.The DNA cleavage intensity was promoted by covalent functionalization,and the intensity of DNA damage caused by the three types of carbon nanotubes in a descending order was found to be carboxylated SWNTs（SWNT-COOH）〉polyethyleneglycol-lated SWNTs（SWNT-PEG）〉uncovalent functionalized SWNTs（uSWNTs）.SWNTs were efficient intermediate to trigger electron transfer from electron donor to O2 in dark condition which lead to superoxide radical（O·-2） formation.The electron transfer intensity caused by selected SWNTs was also SWNT-COOH〉SWNT-PEG〉SWNTs.The reason is that defect sites which changed from sp2-hybridized carbon atom on the side wall of carbon nanotubes were more reactive than the perfect ones.

关 键 词：单壁碳纳米管 共价功能化 DNA损伤 NADH ROS 

分 类 号：X171.5[环境科学与工程—环境科学]