[Determination of ten alkaloids in cosmetics by high performance liquid chromatography-tandem mass spectrometry]

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established for the determination of ten alkaloids in cosmetics. Extraction conditions, purification methods and instrumental parameters were optimized. The samples were ultrasonically extracted with 80% (v/v) methanol aqueous solution. The extracts were separated and filtered after centrifugation. The analytes were separated on a Waters BEH C₁₈ column, and detected in the selected reaction monitoring mode. Ten alkaloids were quantified by the external standard method. The ten alkaloids showed good linearity with correlation coefficients (R²) greater than 0.9900. The limits of detection (LODs) and the limits of quantification (LOQs) of the ten alkaloids were in range of 5.0-12.5 μg/kg and 12.5-50.0 μg/kg, respectively. The average spiked recoveries in the cosmetics ranged from 70.91% to 116.75%, and the relative standard deviations (RSDs) ranged from 0.49% to 9.98%. The method can be used for the rapid screening and quantitative analysis of ten alkaloids in cosmetics.