气相色谱-串联质谱法检测化妆品中25种防腐剂

建立了气相色谱-串联质谱（GC-MS/MS）同时测定化妆品中苯甲酸及其酯类、对羟基苯甲酸酯类、苯氧异丙醇、氯苯甘醚、脱氢乙酸、2，6-二叔丁基-4-甲基苯酚、甲基氯异噻唑啉酮和甲基异噻唑啉酮等25种防腐剂的方法。化妆品样品经含0.1 mg/mL L（+）-抗坏血酸甲醇溶液超声提取，以2-辛醇、苯酚、七氯为内标，加入无水硫酸钠脱水，离心过滤后，用GC-MS/MS分析，内标法定量。方法的检出限为0.08~0.99 μg/kg。实验选取了水、乳液、膏霜型3种类型的化妆品基质，在4个加标水平下验证方法的准确度，25种防腐剂的加标回收率为82.3%~119.4%，RSD为0.2~14.3%（n=6）。该方法定性、定量准确，可有效用于化妆品中25种防腐剂的检测。

Determination of 25 preservatives in cosmetics by gas chromatography-tandem mass spectrometry

A method was developed for the simultaneous determination of benzoic acid and its esters, parabens, phenoxyisopropanol, chlorphenesin, dehydroacetic acid, 2,6-di-tert-butyl-4-methylphenol, methylchloroisothiazolone, methylisothiazolone and other preservatives in cosmetics by gas chromatography-tandem mass spectrometry (GC-MS/MS). The samples were extracted ultrasonically with a 0.1 mg/mL L(+)-ascorbic acid menthol solution after being spiked with a mixture solution of 2-octanol, phenol and heptachlor as internal standards and anhydrous sodium sulfate as a dehydrating reagent. Finally, the extract was centrifuged, filtered, and then analyzed by GC-MS/MS. The analytes were separated using an HP-5MS capillary column (30 m×0.25 mm×0.25 μm) with a temperature-programming program. The inlet, transfer line and ion source temperatures were set to 260, 250 and 230℃, respectively. Helium (99.999%) was used as the carrier gas at a flow rate of 1 mL/min. The final extract (1 μL) was injected in split mode (10:1). Analysis was performed in the multiple reaction monitoring (MRM) mode. Three types of cosmetics, as well as water, milk and cream as samples were selected to verify the accuracy of the method at four levels. The average spiked recoveries ranged from 82.3% to 119.4% with relative standard deviations (n=6) of less than 14.3%. The limits of detection were lower than 0.99 μg/kg for all the preservatives. The method is sensitive, and reliable for the simultaneous determination of the 25 preservatives in cosmetics. Nonetheless, complementary methods need to be developed for the determination of some other preservatives that cannot be detected by GC-MS/MS.