分子印迹聚合膜在电化学传感器中应用-无机化学专业论文.docxVIP

PAGE PAGE IV electrochemical response of copper ion at the modified electrode. The result shows that there is a linear range between the current and concentration of copper ion in 3×10-6～5×10-5 mol/L with a relative coefficient of 0.9972 and the detection limit is 1×10-7 mol/L. The sensor shows high selectivity toward copper ion in the presence of Ni2+, Co2+ and Zn2+. Because electropolymerization has some attractive features including the easy adherence of the polymeric films to the surface of conducing electrodes of any shape and size and the ability to control thickness of the films under different deposition conditions, electropolymerization as a novel strategy for preparation of MIM-electrochemical sensors attracts increasing interest in recent years. A novel MIM-electrochemical sensor for salicylic acid (SA) has been synthesized firstly by electropolymerizing o-phenylenediamine on glassy carbon electrode in presence of template molecule (salicylic acid). The insulating property of the polymeric film is investigated by cyclic voltammetry in the 0.5mol/L KCl solution containing 5mmol/L K3Fe(CN)6. Moreover, electrochemical behaviors of SA are investigated in 2×10-4mol/L SA Britton-Robinson buffer. In the first cycle, only an oxidation peak(O1) appears at potential around 1.110V and no complementary reduction peak is observed. However, a reduction peak(R1) is detected at potential around 0.731V. In the second cycle, a new couple peaks are defined at potential 0.730 and 0.778V. The response of the sensor to SA is investigated by square wave voltammetry (SWV). The linearity is obtained over a concentration range of 6×10-5 ~1×10-4 mol/L (R2=0.9961). And the detection limit of SA is about 2×10-5mol/L. The sensor exhibits good selectivity for salicylic acid by virtue of the interaction between molecularly imprinted binding sites and the template. Molecularly imprinted polymers are synthesized with salicylic acid as the template, acrylamide as func