HPLC-MS/MS法测定化妆品中α-羟基酸的含量

目的：采用高效液相色谱-串联质谱法建立化妆品中5种α-羟基酸，酒石酸、苹果酸、乳酸、柠檬酸、乙醇酸的含量测定方法。方法：采用ZORBAX SB-C₁₈（4.6 mm×75 mm，3.5 μm）色谱柱，以0.1%甲酸水溶液-甲醇（98∶2）为流动相，流速0.4 mL·min^-1，柱温25℃，电喷雾离子源（ESI），多反应离子检测（MRM）扫描方式进行检测。结果：酒石酸、苹果酸、乳酸、柠檬酸和乙醇酸质量浓度分别在10.07~100.7、2.005~20.05、48.72~487.2、1.009~10.09和101.8~1 018 μg·mL^-1的范围内线性关系良好（r>0.997），3种浓度水平平均加样回收率分别在102.6%~115.0%、101.2%~105.2%、102.9%~108.3%、97.8%~98.8%和100.4%~113.3%范围内。4批样品中酒石酸、苹果酸均未检出，乙醇酸均有检出含量分别在3.31%~10.02%，1批样品检出乳酸含量为1.51%，1批样品检出柠檬酸含量为0.03%。结论：所建立的方法简便灵敏，重复性好，可用于化妆品中α-羟基酸的含量测定。

Objective: To establish the method of the determination of five α-hydroxy acids, tartaric acid, malic acid, lactic acid, citric acid and hydroxyacetic acid in cosmetics by HPLC-MS/MS. Methods: The sample was separated on the ZORBAX SB-C₁₈ column(4.6×75 mm, 3.5 μm), with elution by 0.1% aqueous formic acid-methanol(98:2). The flow rate was 0.4 mL·min^-1, and the column temperature was 25℃. The analytes were detected by tandem mass spectrometry with the electrospray ionization(ESI) source combined with multiple reaction monitoring(MRM) mode. Results: Linearity of tartaric acid, malic acid, lactic acid, citric acid and hydroxyacetic acid standards were established within the range of 10.07-100.7 μg·mL^-1, 2.005-20.05 μg·mL^-1, 48.72-487.2 μg·mL^-1, 1.009-10.09 μg·mL^-1 and 101.8-101 8 μg·mL^-1 with the correlation coefficient above 0.997, respectively. The recoveries on three concentration levels were 102.6%-115.0%, 101.2%-105.2%, 102.9%-108.3%, 97.8%-98.8% and 100.4%-113.3%. Tartaric acid and malic acid were not detected in four samples. The contents of hydroxyacetic acid were 3.31%-10.02%. The content of lactic acid was 1.51% in one sample. The content of citric acid was 0.03% in one sample. Conclusion: The method is simple, sensitive and well repeatable. It can be used for the determination of α-hydroxy acids in cosmetics.