Electrochemical Sensor for Detection of Trichlorfon Based on Molecularly Imprinted Sol-Gel Films Modified Glassy Carbon Electrode

Thin films of molecularly imprinted sol-gel polymer with specific binding sites for trichlorfon were prepared, fixed on glassy carbon electrodes and used as recognition material. The binding characteristic of the imprinted films to trichlorfon was evaluated by equilibrium binding experiments; and, the morphology was studied by scanning electronic microscope. A novel electrochemical sensor for determination of trichlorfon was developed based on the reaction between trichlorfon and the molecularly imprinted sol-gel film, which was a modified glassy carbon electrode. The sensor displayed excellent selectivity and high sensitivity. The linear response range of the sensor was 10(-8) - 10(-6) g mL(-1), and the limit of detection was 2.8 x 10(-9) g mL(-1). The relative standard deviation for the determination of 10(-7) g mL(-1) trichlorfon was 3.5%. The sensor was applied to the determination of trichlorfon in vegetables with satisfactory results.