高效液相色谱-二极管阵列检测法快速测定化妆品中褪黑激素

建立了一种简单、快速测定化妆品中褪黑激素的分析方法。样品经甲醇提取后经反相C18柱(4.6×250 mm,5μm)分离,体积比65∶35的水-乙腈作为流动相,等度洗脱,流速为1.0 mL/min,二极管阵列检测器进行检测,检测波长为223 nm,外标法定量。在优化实验条件下,褪黑激素在0.5~100 mg/L范围内线性关系良好,在空白化妆品中添加0.5、5.0、50.0 mg/kg 3个浓度水平时,得到的回收率为91%~101%,相对标准偏差为2.1%~3.9%。方法的检出限(S/N=3)为1.0 mg/kg,定量限(S/N=10)为5.0 mg/kg。该方法简单、快速、准确,可满足化妆品中褪黑激素的检测要求。

Rapid Determination of Melatonin in Cosmetics by HPLC-DAD

A simple and rapid method was developed for the determination of melatonin in cosmetics. The sample was extracted by methanol and separated by a RP C18 chromatographic column（4.6×250 mm, 5 μm） at a flow rate of 1.0mL/min. Water-Acetonitrile（65;35, V/V） was used as mobile phase. The detection of melatonin was performed at 223 nm by using high performance liquid chromatography-diode array detection（HPLC-DAD）. The external standard method was employed for quantitative analysis. Under the optimized condition, the calibration curve was linear in the range of 0.5-100 mg/L. The average recoveries at three spiked levels of 0.5, 1.0, 50.0 mg/kg were between 91% and 101%, with relative standard deviations of 2.1%-3.9 %. The limits of detection （LODs, S/N=3） was 1.0 mg/kg and the limits of quantitative （LOQs, S/N=10） was 5.0 mg/kg. The method was simple, rapid, accurate and could meet the requirement for determination of melatonin in cosmetics.