基于DNA-单壁纳米碳管复合修饰电极的双酚A电化学传感器  

An electrochemical sensor for bisphenol a based on a DNA-single walled carbon nanotube modified electrode

作　　者：蒋晓华[1] 丁文捷[1] 栾崇林[1] 

机构地区：[1]深圳职业技术学院应用化学与生物技术学院,深圳518055

出　　处：《分析试验室》2013年第8期58-62,共5页Chinese Journal of Analysis Laboratory

基　　金：深圳职业技术学院重点项目(NO.2210K3070014);广东省高等学校"千百十工程"人才培养专项基金资助

摘　　要：利用单壁纳米碳管(SWNT)优异的电学性能和催化特性以及DNA特定的分子识别功能,成功构建了一种高灵敏度、快速测定双酚A(BPA)的电化学传感器。在pH7.0的磷酸缓冲溶液中,BPA在SWNT-DNA复合修饰电极上的氧化电流信号是空白电极上的10倍。在10～200 mV/s扫速范围内,氧化峰电流与扫速呈线性关系,表明该氧化过程受吸附控制,通过理论计算,BPA在修饰电极上的反应是一个双电子和双质子过程。在最优的实验条件下,采用差分脉冲伏安法(DPV)对BPA进行测定,氧化电流与BPA浓度在1.0×10-8～2.0×10-5mol/L范围内呈良好的线性关系(r=0.9954),检出限为5.0×10-9mol/L(S/N=3)。该方法初步用于实际样品分析,BPA的加标回收率为93.1%～109.3%。A high sensitive electrochemical method was established for the fast determination of bisphenol A（BPA）,which took advantage of the excellent conductivity and good catalytic ability of single-walled carbon nanotube（SWNT） and the specific molecular recognition capability of DNA.The oxidation peak current of BPA at the SWNT-DNA modified glassy carbon electrode（GCE） was nearly 10-fold of the response at the bare GCE.The oxidation peak current was proportional to the scan rate from 10 to 200 mV /s,which indicated that the oxidation process at the modified electrode was an absorption-controlled wave.The electrochemical oxidation of BPA was a two-electron and two-proton process.Under the optimal conditions,BPA displayed a linear response at the GCE modified with CTDNA-SWNT composite in the concentration range of 1.0 × 10-8 mol /L to 2.0 × 10-5 mol /L.The detection limit was 5.0 × 10-9 mol /L（S /N = 3）.And this method was successfully applied to the estimation of BPA in real samples,with the recoveries in the range from 93.1% to 109.3%.

关 键 词：双酚A 单壁纳米碳管 DNA 电化学方法 

分 类 号：O657.1[理学—分析化学]