气相色谱-质谱法测定水产品中15种邻苯二甲酸酯类塑化剂的残留量

摘要

建立了同时测定水产品中15种邻苯二甲酸酯类塑化剂残留的气相色谱-质谱(GC-MS)分析方法.样品经二氯甲烷-正己烷(1∶1)混合溶液超声萃取,中性氧化铝玻璃层析柱净化,用正己烷、二氯甲烷-正己烷(1∶9)混合液、乙酸乙酯-正己烷(1∶4)混合液和乙酸乙酯依次洗脱目标物,洗脱液经浓缩后正己烷定容,气相色谱-质谱测定.结果显示,15种邻苯二甲酸酯的线性范围为0.05～1.0 mg/L,相关系数(r)不小于0.999 1,检出限(LOD,S/N=3)为0.04～1.18 μg/kg,定量下限(LOQ,S/N=10)为0.20～4.00μg/kg,不同水产品样品中添加2、50、200 μg/kg的15种PAEs,平均加标回收率为81％～123％,相对标准偏差(RSDs,n=3)均小于15％.该方法稳定、可靠、操作简便,适用于鱼肉等水产品中多种PAEs的同时检测与确证.%A method was developed for the simultaneous determination of 15 phthalic acid esters at trace level in aquatic products by solid phase extraction(SPE) purification coupled with gas chromatography-mass spectrometry(GC-MS).The PAEs were extracted with dichloromethane-hexane (1 ∶ 1) by ultrasonic-assisted technique,then purified with SPE glass column packed with 3.0 g neutral alumina caped with approximately 2 cm anhydrous sodium sulfate on the top.The target analyres were eluted with hexane,dichloromethane-hexane (1 ∶ 9) mixture,ethyl acetate-hexane (1 ∶ 4)mixture,and ethyl acetate,sequentially.The eluent was evaporated to near dryness,and redissolved in 1 mL hexane,and analyzed by GC-MS under the selected ion monitoring mode.Under optimized conditions,the linear ranges of 15 phthalic acid esters were in the range of 0.05-1.0mg/L with correlation coefficients(r) not less than 0.999 1.The average recoveries of 15 phthalic acid esters in different kinds of fishery products samples at spiked levels of 2,50,200 μg/kg were in the range of 81％-123％,with relative standard deviations(RSDs,n =3) less than 15％.The limits of detection(LOD,S/N =3) ranged from 0.04 μg/kg to 1.18 μg/kg,and the limits of quantitation(LOQ,S/N =10) ranged from 0.20 μg/kg to 4.00 μg/kg.The proposed method is suitable for the simultaneous determination of 15 phthalic acid esters in fishery products with easy operation,high accuracy and precision.