Simultaneous determination of eight progesterone derivatives residues in milk by ultra-fast liquid chromatography coupled with tandem mass spectrometry

Objective:To establish a method for the simultaneous determination of eight progesterone derivatives residues,such as 21-alpha-hydroxyprogesterone,17-alpha-hydroxyprogesterone,ethisterone,medroxyprogesterone,megestrol acetate,chlormadinone acetate,medroxyprogesterone acetate and progesterone,in milk by ultra-fast liquid chromatography coupled with tandem mass spectrometry(UFLC-MS/MS).Methods: After the milk was extracted by methanol and cleaned and enriched by Waters Oasis HLB solid-phase extraction(SPE) cartridge,separation was performed on a Shim-pack XR-ODSⅡ(100 mm×2.0 mm i.d.,2.2 μm) fast column by the mobile phase of acetonitrile and water with gradient eluent,which contained 0.5%(V/V) formic acid and 5.0 mmol/L ammonium acetate.Detection was carried out by UFLC-MS/MS using a positive electrospray ionization interface in the multi-reaction monitoring(MRM) mode.Results: Calibration curves were linear within the range of 0.5 μg/kg～50.0 μg/kg with the correlation coefficients of more than 0.999,and the limits of quantification(LOQs)were between 0.1 μg/kg～0.5 μg/kg.The extraction recoveries were 73.0%～97.5%,and the RSDs were between 3.8%～8.6%.Conclusion: The developed method is simple,sensitive,accurate and good specificity for the satisfactory determination of trace progesterone derivatives residues in milk.