Electrochemical determination of 2,4-D at a mercury electrode

An indirect electrochemical determination of 2,4-dichlorophenoxyacetic acid (2,4-D), has been presented. The method is based on the adsorption and desorption of 2,4-D on mercury electrode. Also, the electrochemical behavior of 2,4-D in aqueous solutions at different pH values and different 2,4-D concentrations were studied. A simple and rapid method has been developed for its extraction from water and soil. The subsequent determination was carried out by a tensammetric method. Three calibration curves could be obtained from different parts of voltammogram. Under the optimum conditions (pH = 2.3; E-acc = -1100 mV; t(acc) = 60 s; alternative current mode; v = 40mV s(-1); pulse height = 20 mV; modulation frequency = 60 Hz; phase angle = 90degrees) the limit of detection was 50 mug L-1. The proposed method was applied to the determination of 2,4-D in real samples such as soil and water. (C) 2004 Elsevier B.V. All rights reserved.