Detection and mechanistic investigation of halogenated benzoquinone induced DNA damage by photoelectrochemical DNA sensor
Detection and mechanistic investigation of halogenated benzoquinone induced DNA damage by photoelectrochemical DNA sensor
复制标题
光电化学DNA传感器检测卤代苯醌诱导的DNA损伤并研究机理
DOI：
10.1007/s00216-010-3796-3
复制
发表时间：
2010-07-01
影响因子：
4.3
通讯作者：
Guo, Liang-Hong
中科院分区：
文献类型：
--
作者：
Jia, Suping;Zhu, Ben-Zhan;Guo, Liang-Hong
卤代酚被广泛用作杀菌剂，并被认为可能对人类致癌。在本报告中，利用先前开发的光电电化学DNA传感器来研究四卤化醌（卤化酚的体内代谢产物）诱导的DNA损伤。传感器表面由组装在sno2半导体电极上的双链DNA膜组成。DNA插入剂Ru(bpy)2(dppz)2+在光照射下与DNA膜结合并产生光电流。将DNA膜暴露于300 μM的四氟-1,4-苯醌（TFBQ）中，光电流下降20%。在300 μM TFBQ和2mm H2O2的混合物中，信号下降了40%。信号减少表明由于膜中ds-DNA的结构破坏，Ru(bpy)2(dppz)2+的结合减少。四-1,4-氯苯醌（TCBQ）也得到了类似的结果，尽管信号没有TFBQ降低那么多。荧光测定表明，TFBQ/H2O2比TCBQ/H2O2产生更多的羟基自由基。凝胶电泳证明，这两种苯醌类化合物产生的DNA链在H2O2的作用下断裂，而不是自己断裂。利用光电电化学传感器，还发现与DNA共价结合的TCBQ在H2O2存在下不会产生额外的氧化损伤。综合光电化学、凝胶电泳和荧光数据显示，TFBQ和TCBQ在DNA加合物形成和羟基自由基生成方面存在显著差异。数字
Halogenated phenols are widely used as biocides and are considered to be possibly carcinogenic to humans. In this report, a previously developed photoelectrochemical DNA sensor was employed to investigate DNA damage induced by tetra-halogenated quinones, the in vivo metabolites of halogenated phenols. The sensor surface was composed of a double-stranded DNA film assembled on a SnO2semiconductor electrode. A DNA intercalator, Ru(bpy)2(dppz)2+, was allowed to bind to the DNA film and produce photocurrent upon light irradiation. After the DNA film was exposed to 300 μM tetrafluoro-1,4-benzoquinone (TFBQ), the photocurrent dropped by 20%. In a mixture of 300 μM TFBQ and 2 mM H2O2, the signal dropped by 40%. The signal reduction indicates less binding of Ru(bpy)2(dppz)2+due to structural damage of ds-DNA in the film. Similar results were obtained with tetra-1,4-chlorobenzoquinone (TCBQ), although the signal was not reduced as much as TFBQ. Fluorescence measurement showed that TFBQ/H2O2generated more hydroxyl radicals than TCBQ/H2O2. Gel electrophoresis proved that the two benzoquinones produced DNA strand breaks together with H2O2, but not by themselves. Using the photoelectrochemical sensor, it was also found that TCBQ covalently bound with DNA did not produce additional oxidative damage in the presence of H2O2. The combined photoelectrochemistry, gel electrophoresis, and fluorescence data revealed distinctive differences between TFBQ and TCBQ in terms of DNA adduct formation and hydroxyl radical generation.Figure