QuEChERS sample preparation in the simultaneous determination of diethylstilbestrol and ractopamine in food by gas-liquid chromatography

A simple and rapid method has been proposed for the determination of 1–25 μg/kg of diethylstilbestrol and β-adrenostimulator ractopamine in food by gas-liquid chromatography with an electron-capture detector. The extraction of the target components was performed by the QuEChERS method; the additional purification of the extract and preconcentration in the determination of diethylstilbestrol has been performed by dispersion liquid-liquid microextraction with tetrachloromethane. Recovery was 92–110% and preconcentration factor, 40. The time of analysis is 1.5–2 h; the relative standard deviation of the results of analysis does not exceed 10 %.