QuEChERS前处理技术与在线凝胶渗透色谱-气相色谱质谱联用法测定蔬菜水果中20种农药残留

Determination of 20 kinds of pesticide residues in vegetables and fruits by Qu ECh ERS pretreatment technology and online gel permeation chromatography-gas chromatography/mass spectrometry

目的建立在线凝胶渗透色谱-气相色谱质谱（online gel permeation chromatography-gas chromatography/mass spectrometry,GPC-GC/MS）联用法测定蔬菜、水果中有机磷、氨基甲酸酯、拟除虫菊酯类20种农药残留的分析方法。方法蔬菜、水果中有机磷、氨基甲酸酯、拟除虫菊酯类20种农药残留经过乙腈与Qu ECh ERS试剂包提取、净化、浓缩,经在线凝胶渗透色谱-气相色谱质谱仪分析测定,选择离子模式定量。结果 GPC-GC/MS系统中的GPC弥补了Qu ECh ERS方法净化干扰物质不彻底的问题,从而降低分析背景,改善峰形,提高分析结果的准确性和相关质谱图匹配性。在0.01 mg/kg加标情况下,3种样品（芹菜、桔子和韭菜）除桔子和韭菜中甲胺磷、敌敌畏和氧化乐果由于基质的影响而回收率偏低外,其他均在80%~120%,3种样品平行样的相对标准偏差均在15%以下,并且该方法与传统的固相萃取小柱净化法进行加标比对,回收率无明显差异。结论 Qu ECh ERS方法和GPC-GC/MS联合使用分析蔬菜水果中的农药残留,达到了快速、简单、便宜、有效、可靠和安全的目的。

Objective including organochlorine, technology and online （GPC-GC/MS）. Methods To establish a new method for the determination of 20 kinds of pesticide residues, pyrethroid and acaricide, in vegetables and fruits by QuEChERS pretreatment gel permeation chromatography-gas chromatography/mass spectrometry Samples of vegetables and fruits were concentrated by acetonitrile and QuEChERS reagent, and detected by online GPC-GC/MS. Ion monitoring mode was selected for quantitative analysis. Results Compared with GC/MS, online GPC-GC/MS system had the lower interfered background and better peak shape. Identification and quantization of pesticide residues with online GPC-GC/MS could be well performed. The recoveries of all pesticides including 3 spiked samples （celery, oranges and leeks） at the level of 0.01 mg/kg were 80%-120% and the RSD was less than 15%, except methamidophos, dichlorvos and omethoate in oranges and leek. Compared with the traditional purification method, the recovery rate had no obvious difference. Conclusion QuEChERS method combined with GPC-GC/MS system can be used to achieve the purpose of fast, simple, cheap, effective, rugged and safe for the determination of pesticide residues in vegetables and fruits.