Simultaneous Determination of Seven Adulterants in Functional Foods by High-Performance Capillary Electrophoresis

A high-performance capillary electrophoresis method has been established for the simultaneous determination of seven functional food adulterants, namely, fenfluramine, pseudoephedrine, norpseudoephedrine, amfepramone, sibutramine, sildenafil, and strychnine. A mixture of 20 mM sodium tetraborate-10 mM sodium dodecyl sulfate-5% acetonitrile was used as a running buffer (pH 9.0), and analysis was carried out at a detection wavelength of 195 nm under a separation voltage of 17 kV at 25 °C. The upper limit of the linear ranges was 100 mg L−1, with the linear correlation coefficients being greater than 0.998. The relative standard deviations ranged between 4.5% and 7.9% (n = 7). The average recoveries were in the range of 79.6%–112.0%. The limits of detection (three times the signal-to-noise ratio, S/N = 3) were between 0.16 and 0.65 mg L−1. The method is simple, fast, sensitive, accurate and cheap. It has been successfully applied for the determination of the seven target chemicals in functional foods