Capacitive detection of theophylline based on electropolymerized molecularly imprinted polymer

The capacitive sensor was prepared by electropolymerization of phenol onto the surface of gold electrode. By using AC impedance measurements, the sensor is based on the decrease in capacitance caused by the analyte used as the template in the formulation of an electropolymerized molecularly imprinted polymer as receptor layer. Improvement of the insulating properties of the sensor was investigated in detail. Electrochemical impedance ( EI) was used to characterize the modified gold electrodes. Unlike the capacitive sensors reported previously, the present sensors were not treated with alkanethiol after the electropolymerization and show even more satisfactory performance.