Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Biosens Bioelectron. 2011 Jun 15;26(10):4040-5. doi: 10.1016/j.bios.2011.03.027. Epub 2011 Apr 2.
In this work, an electrochemical DNA biosensor based on double-stranded DNA modified Au electrode (dsDNA/Au) was proposed for the rapid screening and detection of chlorinated benzenes pollutants, in which redox-active methylene blue (MB) was used to amplify the interaction between dsDNA and the target analyte. Using hexachlorobenzene (HCB) as a model analyte of chlorinated benzenes, the biosensor demonstrated a linear response with the logarithm of HCB concentrations from 100 pmol L(-1) to 100 nmol L(-1). The obtained detection limit was 30 pmol L(-1), which was remarkably superior to other biosensors. The interaction mechanism of the biosensor with HCB was proposed based on systematical characterization by cyclic voltammetry (CV), differential pulse voltammetry (DPV), UV-vis spectrometry and electrochemical quartz crystal microbalance (EQCM). Further studies revealed that the biosensor could screen chlorinated benzenes in the presence of 100 fold amount of other co-existing chemicals (ethyl acetate and sodium oxalate, etc.), and the response signal of the biosensors for different chlorinated benzenes was correlative to their respective toxicity. The proposed biosensor proved to be a promising "alarm" tool for rapid screening of chlorinated benzenes in real water samples.
在这项工作中，提出了一种基于双链 DNA 修饰金电极（dsDNA/Au）的电化学 DNA 生物传感器，用于快速筛选和检测氯苯污染物，其中氧化还原活性的亚甲基蓝（MB）被用于放大 dsDNA 与目标分析物之间的相互作用。使用六氯苯（HCB）作为氯苯的模型分析物，该生物传感器在 HCB 浓度从 100 pmol L(-1) 到 100 nmol L(-1) 的对数范围内表现出线性响应。获得的检测限为 30 pmol L(-1)，明显优于其他生物传感器。基于循环伏安法（CV）、差分脉冲伏安法（DPV）、紫外-可见光谱法和电化学石英晶体微天平（EQCM）的系统表征，提出了该生物传感器与 HCB 的相互作用机制。进一步的研究表明，该生物传感器可以在存在 100 倍量的其他共存化学物质（乙酸乙酯和草酸钠等）的情况下筛选氯苯，并且生物传感器对不同氯苯的响应信号与它们各自的毒性相关。所提出的生物传感器被证明是一种有前途的“警报”工具，可用于快速筛选实际水样中的氯苯。
