镍配合物分子印迹光电流型传感器的研究

Study on Molecularly Imprinted Sensor Based on Photocurrent Response for Ni-complex

制作了一种基于光电流检测的分子印迹传感器,并应用于Ni^(2+)测定。此传感器以Cd Te量子点为光电材料,将量子点覆盖在导电玻璃表面,并在此层上以光聚合法制作镍-1-(2-吡啶偶氮)-2-萘酚(PAN)分子印迹膜。365 nm紫外光作为激发光源,量子点在光照下生成电子-空穴对,电子与电子受体-抗坏血酸作用形成的光电流作为检测信号,根据"门效应"进行Ni2+检测。实验中对配合物进行了红外表征,对量子点进行了紫外和荧光表征,对洗脱吸附时间和底液中抗坏血酸浓度的用量进行了优化。实验表明Ni2+浓度在5×10^(-11)~5×10^(-8)mol/L的范围内与光电流大小呈线性关系,检出限达8.3×10^(-12)mol/L。此传感器具有较好的选择性,已用于水样分析。

A novel molecularly imprinted sensor for Ni^（2＋）detection was fabricated based on photocurrent method. Cd Te quantum dot（ QDs） was selected as photoelectric material and modified in ITO electrode,then the nickel-1-（ 2-pyridylazo）-2-naphthol molecularly imprinted film was formed on the QDs layer by photopolymerization. By using 365 nm ultraviolet light as excitation light,the QDs generated electron-hole,and the electron donor-ascorbic acid combined with electron to form the photocurrent signals. Based on this evidence,Ni^（2＋）was detected according to ＂gate-effect＂. The complex was characterized by Fourier transform infrared spectrum and the Cd Te QDs was characterized by ultraviolet absorption spectrum and fluorescence emission spectrum,the time for elution and rebinding and the concentration of ascorbic acid in base solution were optimized. The experiment showed that there was a liner relationship between the photocurrent and the concentration of Ni^（2＋）at 5 ×10^（-11）-5 ×10^（-8）mol / L,with the detection limit of 8. 3 ×10^（-12）mol / L. The sensor also had good selectivity,and it was applied in real water samples analysis.