Determination of 6 Kinds of Sex Hormones in Fish Using Subcritical 1,1,1,2-Tetrafluoroethane Extraction-Gas Chromatography-Tandem Mass Spectrometry

A sample pretreatment method was developed for the analysis of six sex hormones in fish by subcritical 1,1,1,2-tetrafluoroethane (R134a) extraction coupled with gas chromatography-mass spectrometry(GC-MS). After the extraction process was completed, the fatty co-extracted interferent of the sample was removed by freezing filtration. Then the analytes were cleaned up by C18 and NH2 solid phase extraction (SPE) column. At last, the hormones were derivatived by heptafluorobutyric anhydride (HFBA) followed by GC-MS validation. The optima extraction conditions for the six sex hormones were as follows: extraction pressure, 4 MPa; extraction temperature, 30 °C; extraction cosolvent amount, 6 mL. Under these conditions, the calibration curves showed good linearity with correlation coefficients larger than 0.99 in the hormones concentrations of 5–1000 μg L−1; the detection limits were 0.2–1.0 μg kg−1 (S/N = 3). At the spiked level of 1, 5 and 10 μg kg−1, the mean recoveries were between 70.5% and 103.6%, and the relative standard deviations (RSDs) ranged from 2.1% to 12.5%. Finally, diethylstilbestrol was detected in real samples by the proposed method, and the residue content of which was 14.6 μg kg−1.

A new sample pretreatment method was developed for the simultaneous determination of six sex hormones in fish by subcritical fluid extraction coupled with gas chromatography-mass spectrometry (GC-MS). Cosolvent can significantly improve the dissolution performance of subcritical fluids. In this study, the recovery of the six sex hormones increased with the increasing amount of cosolvent.Figure optionsDownload as PowerPoint slide