Electrochemical Sensor for Indole-3-Acetic Acid Based on Molecularly Imprinted Polymers

In the present work,molecularly imprinted polymers(MIPs) membrane on the surface of a glassy carbon electrode with indole-3-acetic acid(IAA) as templet and methacrylic acid as functional monomer was prepared to construct an electrochemical sensor for IAA.Electrochemical oxidation behaviors of IAA on the MIPs modified electrode have been investigated with square wave voltammetry.At oxidation potential of 0.62 V(vs.SCE),the peak currents were proportional to the concentration of IAA in the range of 5.0×10-6~2.0×10-4 mol/L with the detection limit of 5.0×10-6mol/L(S/N=3),and the relative standard deviation of peak current was 1.1%(n=10).The MIPs sensor displayed good selectivity.Tryptophan,dopamine,ascorbic acid and histidine,50,50,20 and 20 times the amount of IAA,respectively,did not interfere with determination of IAA.The MIPs sensor has been applied to analysis of IAA in soybean sprout and mungbean sprout samples,the average recoveries were between 97% and 100%.