纳米氧化铜修饰的苯巴比妥分子印迹传感器的制备及其电化学性能

为了改善分子印迹传感器的灵敏度, 在四丁基高氯酸铵的支持电解质溶液中, 以甲基丙烯酸为功能单体, 马来松香丙烯酸乙二醇酯为交联剂在纳米氧化铜修饰过的玻碳电极上电聚合了一种苯巴比妥(PB)识别性能的分子印迹传感膜. 采用循环伏安(CV)法、差分脉冲伏安(DPV)法及交流阻抗(EIS)法对这种纳米氧化铜修饰过的印迹及非印迹电极的电化学性能进行了研究, 结果显示纳米氧化铜修饰过的印迹及非印迹电极的电化学性能完全不同. X射线衍射(XRD)证实纳米粒子为氧化铜. 采用扫描电镜(SEM)对纳米氧化铜修饰过的印迹传感器的形貌进行分析, 发现纳米氧化铜分散在电极表面, 改善了修饰印迹传感器的识别点. 差分脉冲伏安法(DPV)表明苯巴比妥的浓度在1.0×10^-8-1.8×10^-4 mol·L^-1 范围内呈现良好的线性关系(线性相关系数R=0.9994); 检出限2.3×10^-9 mol·L^-1 (信噪比(S/N)=3). 研究结果表明纳米氧化铜修饰过的印迹传感器具有较高灵敏度及选择性. 此印迹传感器能用于实际样品中苯巴比妥的检测, 加标回收率在95.0%-102.5%.

Preparation and Electrochemical Properties of Phenobarbital Molecularly Imprinted Polymer Sensor Based on a CuO Nanoparticle-Modified Glassy Carbon Electrode

To improve the sensitivity of molecular imprinted electrochemical sensors, a molecularly imprinted polymer (MIP) film for the determination of phenobarbital (PB) was electropolymerized on a CuO nanoparticlemodified glassy carbon electrode. Methacrylic acid was used as the functional monomer and ethylene glycol maleic rosinate acrylate as a cross-linking agent in the presence of supporting electrolyte (tetrabutylammonium perchlorate). The electrochemical properties of CuO nanoparticle-modified molecularly imprinted and non-imprinted polymer (NIP) sensors were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The results showed that the electrochemical properties of the CuO nanoparticle-modified MIP sensor were completely different from those of NIP sensors. X-ray diffraction confirmed that the nanoparticles were CuO. The morphology of the CuO nanoparticle-modified MIP sensor was examined under a scanning electron microscope. The CuO nanoparticles were uniformly distributed on the surface of the modified glassy carbon electrode, which improved the recognition sites of the modified MIP sensor. The response value of the DPV peak current showed linear dependence on the PB concentration in the range 1.0×10^-8 to 1.8×10^-4 mol·L^-1 (linear regression coefficient =0.9994) with a detection limit (S/N=3) of 2.3×10^-9 mol·L^-1. The results indicated that the CuO nanoparticle-modified MIP sensor is one of the most sensitive and selective sensors for PB determination. The prepared sensor was successfully applied for the determination of PB in practical samples and the recovery ranged from 95.0% to 102.5%.