液相微萃取/气相色谱-质谱法分析食品中的防腐剂和抗氧化剂

采用液相微萃取/气相色谱-质谱联用测定食品中的四种防腐剂和三种抗氧化剂。优化后的萃取条件为:2.0μL甲苯作萃取剂,微液滴在样品中深度为0.85cm,搅拌速度800r/min,萃取时间25min,溶液的pH=3,加入盐的质量浓度为10%。该方法线性范围为0.5～400mg/kg,检出限0.01～1.2mg/kg,加标回收率93.7%～113.4%,相对标准偏差2.7%～8.6%。

Determination of Preservatives and Antioxidants in Food by Liquid-Phase Microextraction with Gas Chromatography-Mass Spectrometry

A liquid-phase microextraction (LPME) method was developed for the determination of four preservatives and three antioxidants in food by gas chromatography-ion trap mass spectrometry(GC-IT/MS). The optimal LPME conditions, 2.0 μL of toluene, 0.85 cm of the depth of microdrop, 800 r/min of stirring rate, 25 min of extraction time, 10% salt and pH=3 were obtained. The conditions were used for analysis of preservatives and antioxidants in foods. The analytical results showed that the working curves for 7 preservatives and antioxidants were linear in the range of 0.5～400 mg/kg by GC-MS on selective ion storage mode. The detection limits were between 0.01 mg/kg and 1.2 μg/kg, and the overall recoveries were 93.7% to 113.4% with the relative standard deviations of 2.7%～8.6%.