Objective: To establish a rapid, accurate and sensitive method by liquid chromatography-tandem mass spectrometry with isotope internal standard dilution technique for the determination of chlorpromazine and promethazine and their metabolites in swine tissues.
Methods: The swine tissues sample was extracted with acetonitrile and purified on MCX cartridge. The liquid chromatography separation was performed on an ACQUITY UFLC® HSS T3(100 mm×2.1 mm, 1.8 μm) with a linear gradient elution program of 0.1%(V/V) fomic acid-acetonitrile and 0.1%(V/V) formic acid-water solution as the mobile phase. The analytes were analyzed using ESI operating in the positive multiple reaction monitoring(MRM) mode.
Results: The limits of quantitation(LOQs) and limits of detection(LODs) for the target objects were 0.12-0.51 μg/kg and 0.04-0.17 μg/kg, respectively. The calibration curves were linear in range of 0.1-20.0 μg/L for chlorpromazine and promethazine, and 0.5-100.0 μg/L for their metabolites(chlorpromazine sulfoxide and isopropyl sulfoxide). The recoveries were between 90.8%-106.0%, and the relative standard deviations(RSDs) were between 1.9%-6.2%(n=6).
Conclusion: The method is highly sensitive and accurate, and is suitable for the analysis of chlorpromazine and promethazine and their metabolites(chlorpromazine sulfoxide and isopropyl sulfoxide) in swine tissues.
Keywords: chlorpromazine; chlorpromazine sulfoxide; isopropyl sulfoxide; liquid chromatography-tandem mass spectrometry(LC-MS/MS); promethazine; swine tissues.