Construction of a novel sensor based on electropolymerization of carmine for voltammetric determination of 4-nitrophenol

4-Nitrophenol (4-NP) has been determined with voltammetric technique based on a novel sensor fabricated by electropolymerization of carmine on a glassy carbon electrode (GCE). An obvious reduction peak located at about -0.700 V and a couple of redox peaks that were not well-defined were observed in the potential range of -1.00 to 0.600 V. Compared with its voltammetric behavior on a bare GCE, the reduction peak potential shifted positively and the peak current increased significantly. All experimental parameters were optimized and linear sweep voltammetry was proposed for its determination. In the optimal conditions, the reduction peak current was proportional to the 4-NP concentration over the concentration range from 5.00 x 10(-8) to 1.00 x 10(-5) mol L-1, and the detection limit was 1.00 x 10(-8) mol L-1 after 200 s of accumulation. The high sensitivity and selectivity of the sensor was demonstrated by its practical application for the determination of trace amounts of 4-NP in lake water. (c) 2006 Wiley Periodicals, Inc.