Determination of trace amounts of 3,4-dichloroaniline by high-performance liquid chromatography with amperometric detection and its application to pesticide residue analysis

Summary High-performance liquid chromatography with amperometric detection was used for the determination of trace amounts of 3,4-dichloroaniline. The latter was separated with Nucleosil C₁₈ as stationary phase and methanolwater (70:30 V/V) containing 0.05 mol/l ammonium acetate as eluent. The voltage of the working electrode (glassy carbon) was set at +960 mV vs. Ag/AgCl. The linear dynamic range between limiting current and concentration was about 1×10² (0.2–20 ng) and the minimum detectable amount was 0.2 ng. This method was applied to the determination of trace amounts of linuron and free 3,4-dichloroaniline in potatoes. The minimum quantitative level was 0.01 ppm. The method requires less clean-up steps than the GC and HPLC methods (using UV detection).