Determination of 9 Benzophenones for Ultraviolet Absorber in Cosmetics by High Performance Liquid Chromatography-Tandem Mass Spectrometry

The method for simultaneous determination of the 9 benzophenones for ultraviolet absorber in cosmetics by high performance liquid chromatography-tandem mass spectrometry was established. The sample (0.1 g) was treated in 30 mL of acetonitrile by ultrasonic extraction for 30 min, cooled to room temperature, diluted to 50 mL and filtered. C₁₈ chromatographic column was used as the stationary phase, and a mixture of acetonitrile and 0.1% (φ) formic acid aqueous solution at different volume ratios was used as the mobile phase for gradient elution. The electrospray ionization source (ESI⁺) and multiple reaction monitoring mode were adopted into mass spectrometry analysis, and external standard method was used for quantitative analysis. It was showed that the matrix effect of the sample was small and could be ignored. Linear relationships between mass concentrations of the 9 benzophenones and their response values were kept in the same range of 0.50-500 μg·L^-1, with detection limits (3s/k) in the range of 0.022-0.652 μg·L^-1. The mixed standard solution were determined, with RSDs (n=6) of the determined values less than 5.0%. Test for recovery was made by standard addition method, giving values of recovery in the range of 70.9%-116%. 15 batches of samples were analyzed by this method, and benzophenone-3 was detected in 2 batches, with the detection amounts of 1.53% and 4.67%, and benzophenone-10 was detected in 1 batch, with the detection amount of 0.001 26%.