气相色谱-质谱法同时测定水果中9种保鲜剂的残留量

Abstract

建立了采用气相色谱-质谱(gC-MS)同时测定水果中9种保鲜剂残留量的分析方法。水果样品用正己烷/乙酸乙酯(1/1,V/V)混合提取剂超声提取,经flOrISIl层析柱净化后用正己烷/乙酸乙酯(1/3,V/V)混合洗脱剂洗脱,以磷酸三苯脂(TPP)为内标物,采用gC-MS的全扫描方式(SCAn)和选择离子监测方式(SIM)对9种保鲜剂进行定性与定量分析。实验结果表明,9种保鲜剂的检出限(lOd)为0.10~2.16μg/kg,在50、100、200μg/kg添加水平下的回收率为75.3%~128%,相对标准偏差为1.57%~11.6%。本分析方法样品前处理简便,净化效果明显,在SIM谱图中分析目标物响应值大、灵敏度高,定量准确可靠,能够满足保鲜剂痕量残留的检测要求。

A gas chromatography-mass spectrometry(GC-MS)method was established for the simultaneous determination of nine typical preservatives(pyrimethanil,chlorothalonil,chlorpyrifos, triadimefon,thiabendazole,imazalil,myclobutanil,iprodione,prochloraz)in fruits.The fruit samples were subjected to ultrasonic extraction with hexane/ethyl acetate(1/1,v/v),and followed by purification using diatomite column chromatography with hexane/ethyl acetate(1/3,v/v)eluant.Qualitative and quantitative analysis of the nine preservatives were performed on the GC-MS at full-scan(SCAN)and selected ion monitoring(SIM)modes,in which triphenylphosphate was used as the internal standard.The detection limits obtained for the nine preservatives were ranged from0.10μg/kg to 2.16μg/kg.The average recoveries were in the range of 75.3%to 128% at the spiked levels of 50,100 and 200μg/kg with the relative standard deviations(RSDs)of 1.57% to 11.6%(n=5).The results showed that the developed method is sensitive and accurate for the determination of the nine preservatives in fruits.