聚邻氨基苯硫酚/纳米金复合膜分子印迹传感器测定2, 4-二氯苯酚

在2,4-二氯苯酚(2,4-DCP)存在下, 在金电极表面自组装邻氨基苯硫酚(oATP)并电聚合oATP/金纳米粒子, 制得2,4-DCP印迹复合膜电化学传感器.采用循环伏安法和交流阻抗技术对传感器制备过程进行了表征, 以K₃Fe(CN)₆为探针, 间接对2,4-DCP进行定量分析.结果表明, 2,4-DCP在5.0×10^-8~1.2×10^-4 mol/L 浓度范围内与K₃Fe(CN)₆示差脉冲伏安曲线的峰电流呈线性关系(R²=0.9964), 检出限为1.5×10^-8 mol/L(S/N=3).该印迹传感器可在几种氯代酚干扰下选择性测定2,4-DCP.利用该传感器对环境水样进行加标回收检测, 回收率为95.2%~109.3%.

Molecularly Imprinted Electrochemical Sensor for 2, 4-Dichlorophenol Based on Composite Film of o-Aminothiophenol and Au Nanoparticles

A novel molecularly imprinted electrochemical sensor for 2,4-dichlorophenol(2,4-DCP) detection was fabricated on the surface of gold electrode by self-assembly of o-aminothiophenol(oATP) and electropolymerization of oATP/Au nanoparticles in the presence of template molecule. The modification procedure was characterized via cyclic voltammetry and electrochemical impedance spectroscopy. In the presence of K₃Fe(CN)₆ as redox probe, the peak current of K₃Fe(CN)₆ decreased linearly with the increasing concentration of 2,4-DCP from 5.0×10^-8 to 1.2×10^-4 mol/L(R²=0.9964) with a detect limit of 1.5×10^-8 mol/L(S/N=3). Three chlorophenols possesing analogous structures, including 2,6-DCP, 2,4,6-trichlorophenol(2,4,6-TCP) and pentachlorophenol(PCP) were chosen to examine the specific recognition ability of the imprinted sensor. The results showed that MIP electrode had the highest current response toward 2,4-DCP. In addition, the feasibility of its practical applications has been demonstrated in the analysis of four water samples with the recoveries ranged from 95.2% to 109.3%.