高效液相色谱-二极管阵列检测器同时测定化妆品中的九种染料及中间体

建立了用高效液相色谱-二极管阵列检测器(HPLC-PDA)同时检测9种染料及中间体的系统方法。首先采用超声提取的方法处理样品,对提取溶剂和提取时间进行了选择,确定用甲醇-0.01 mol/L 乙酸铵(体积比为2∶1)作提取溶剂,超声提取20 min。然后，采用C18柱,以甲醇-0.01 mol/L乙酸铵(pH 6.2)为流动相梯度洗脱,用PDA检测。以保留时间定性,并以紫外吸收光谱图辅助定性,以外标法定量。定量检测波长为230 nm,15 min内可对9种目标物同时进行测定,且各化合物都达到基线分离(分离度大于1.5)。经测定,该方法的平均回收率(n=8)为81.0%～105.6%,相对标准偏差（RSD）为0.8%～4.9%,检出限(以信噪比为3计)为0.1～2 μg。该方法简单、快速,能有效提取和分离测定化妆品中9种染料及中间体。将该方法用于实际化妆品样品的检测,结果令人满意。

Simultaneous Determination of Nine Dyestuffs and Dyes Intermediates in Cosmetics by High Performance Liquid Chromatography/Photodiode Array Detection

A new analytical method based on high performance liquid chromatography/photodiode array detection (HPLC/PDA) has been established for the simultaneous determination of nine dyestuffs and dyes intermediates in cosmetics. After the cosmetics were treated by ultrasonic extraction using methanol-0.01 mol/L NH4Ac aqueous solution (2 : 1, v/v), the obtained liquid samples were analyzed by HPLC using a Waters Symmetry C18 column (4.6 mm x 250 mm, 5 microm). Methanol-0.01 mol/L NH4Ac aqueous solution (pH 6.2) was used as the mobile phase for gradient elution. Nine dyestuffs and dyes intermediates were completely separated within 15 min. PDA spectrum was used for assistant identification. External standard method was applied for quantitation. The average recoveries (n = 8) were from 81.0% to 105.6% with relative standard deviations between 0.8% and 4.9%. The detection limits (S/N = 3) were in the range of 0.1 - 2 microg. The method is simple, rapid, accurate and suitable for the determination of nine dyestuffs and dyes intermediates in cosmetics.