Abstract: A method was established for the determination of four progesterones (progesterone, melengestrol acetate, megestrol acetate and chlormadinone acetate) by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with dispersive solid-phase extraction. The samples were extracted with n-hexane and then the extract was redissolved with methanol solution after being evaporated to dryness by nitrogen blowing. The solution was then purified with primary secondary amine (PSA) solid phase adsorbent. Using binary mobile phase gradient with water containing 0.1% formic acid and methanol, the centrifugal supernatant was separated on an ACQUITY UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm) and the target compounds were detected under a multiple reaction monitoring (MRM) mode with a positive electrospray ionization source. The results showed that the calibration curves for the four progesterone hormones exhibited good linear relationships in the range of 0.4–100 μg/L with correlation coefficients (r2) of more than 0.996. The limit of detection was 0.2 μg/kg and the limit of quantification was 0.6 μg/kg. The average recoveries at three spiked levels were 79.5%–99.7% with relative standard deviations (RSD, n = 6) of less than 10.0%. This method proved to be simple, rapid, highly sensitive and practical, and thus it could be applicable for routine determination of the 4 progesterone hormones in eggs.

Key words: dispersive solid-phase extraction, egg, ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), progesterone hormones