气相色谱-质谱法同时测定化妆品中19种邻苯二甲酸酯

建立了同时测定化妆品中19种邻苯二甲酸酯的气相色谱-质谱(GC-MS)方法。样品经二氯甲烷超声提取后,用硅胶-中性氧化铝(2:3, m/m)混合填料固相小柱保留、乙酸乙酯-正己烷(8:2, v/v)洗脱等步骤净化后,采用GC-MS对19种目标物进行定性、定量分析。采用保留时间与特征离子丰度比共同进行定性分析,减少了复杂样品基质中的干扰。在优化的实验条件及0.1、0.5、2.0 μg/g的添加水平下,平均加标回收率为72.2%～110.9%,其中加标水平为0.1 μg/g的相对标准偏差(RSD, n=6)小于10.3%;方法检出限(以3倍标准偏差计)为0.0065 μg/g(邻苯二甲酸二异戊酯)～0.062 μg/g(邻苯二甲酸二异丁酯)之间。应用该方法检测了6种化妆品中19种PAEs的含量。该方法可推广用于多种类型化妆品中PAEs的测定。

Simultaneous determination of 19 phthalate esters in cosmetics using gas chromatography-mass spectrometry

A method was developed for the simultaneous determination of 19 phthalate esters (PAEs) at trace level in cosmetics by solid phase extraction (SPE) purification and gas chromatography-mass spectrometry (GC-MS) detection. The PAEs were extracted from cosmetic samples by dichloromethane with ultrasonic-assisted technique, purified by an SPE column packed with silica gel and neutral alumina (2: 3, m/m) with the elution of 20 mL of mixed solvent of ethyl acetate-hexane (8: 2, v/v). Qualitative and quantitative analysis were carried out by GC-MS in full scan and selected ion monitoring modes. The retention time of quantitative ions and the abundance ratio of characteristic ions were applied to rapidly and accurately identify each analyte so as to prevent the occurring of possible mistakes from complex matrix intervention. Under optimized conditions, the average recoveries for a shampoo sample spiked with the standards at 0.1, 0.5, 2.0 microg/g were in the range of 72.2% and 110.9%, and the relative standard deviations (RSDs) for the 19 PAEs were less than 10.3% (n = 6) at the spiked level of 0.1 microg/g. The limits of detection (LODs, as 3 times of standard deviation) were between 0.0065 microg/g (for diisopentyl phthalate) and 0.062 microg/g (for diisobutyl phthalate). The method was successfully applied to the determination of the PAEs in 6 types of cosmetics. It is expected to promote the determination of the PAEs in other cosmetics with different matrices.