Determination of imperatorin and isoimperatorin in cosmetics by high performance liquid chromatography-tandem mass spectrometry

A novel method for the simultaneous determination of imperatorin and isoimperatorin in cosmetics by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed. The imperatorin and isoimperatorin were extracted by methanol. The analytes were separated on a C-18 column using 10 mmol/L ammonium acetate/ methanol-5 mmol/L ammonium acetate aqueous solution (80:20, v/v) as mobile phase, and then detected by HPLC-MS/MS using multiple reaction monitoring (MRM) mode. The good linearities (r > 0.999) were achieved for the target compounds over the range of 0.25-20 mu g/L. The limits of quantification (LOQs) were 0.5 mg/kg. The recoveries for the imperatorin and isoimperatorin varied from 82.2% to 105% and 80.0% to 103% with the relative standard deviations ranging from 2.7% to 4.9% and 1.8% to 4.6% respectively in the range of 0.50-10.0 mg/kg. The method can meet the requirements for the simultaneous determination of imperatorin and isoimperatorin in cosmetics.