超声萃取-气流式液相微萃取-气相色谱质谱在线联用快速检测蔬菜中有机磷农药残留(英文)

Ultrasonic extraction and gas flow liquid phase microextraction coupled with on-line gas chromatography-mass spectrometry:Rapid determination of organophosphorus pesticides residues in vegetables

建立超声萃取—气流式微注射萃取—在线气相色谱质谱联用（GPMSE—GC—MS）快速测定蔬菜中代表性有机磷农药残留的检测方法。样品经乙酸乙酯超声提取,气流微注射萃取仪（GP—MSE）净化、富集,在线以气相色谱质谱的选择监控离子模式进行定性定量测定。考察GP—MSE的气流速率、样品相温度、萃取时间、萃取溶剂等因素对萃取效率的影响,以10μL的正己烷为萃取、富集溶剂,GP—MSE的气体流速2.0min/mL,萃取相温度250℃,萃取时间为3min,在线进样进行GC—MS分析。结果表明,28种农药在各自的线性范围内线性关系良好（相关系数不低于0.99）,检出限（以信噪比（S/N）为3计算为0.3-1.2μg/kg,定量限（S/N=10）为3.0-10.0μg/kg。在两种基质（大白菜、芹菜）中3个添加水平下的回收率为80.2%-122.6%,相对标准偏差为1.6%-12.1%。与固相萃取比较。该方法提取效率高,定性定量准确、灵敏,可实现对蔬菜中多农药残留的快速检测,对保障蔬菜安全,促进蔬菜出口具有重要意义。

An analysis method was established on rapid determination of organophosphorus pesticides （OPPs） residues in vegetables using ultrasonic extraction and gas flow liquid phase microextraction cou- pled with on-line gas chromatography-mass spectrometry （UAE-- GPMSE--GC- MS）. The samples were extracted by ultrasonic techniques with ethyl acetate and re-extracted by gas flow liquid phase microextraction （also known as gas flow-microsyringe extrac- tion, GP--MSE） for purification and enrichment. The optimal conditions of the GP--MSE were as follows= 10 μL of n-hexane was used as an enrichment solvent, the gas flow rate was 2.0 min/mL, the temperature of the sample phase was 250 ℃, and the extraction time was 3 min. Then, the secondary extraction was directly injected into gas chromatography-mass spectrometry （GC--MS） system, and 28 types of OPPs in vegetable samples were determined in selected ion mode （SIM）. The UAE--GPMSE--GC--MS analysis system demonstrated a good linear relationship （the correlation coefficient not less than 0. 99）, and the detection limits （S/N=3） and the quantification limits （S/N = 10） were 0. 3- 1. 2 μg/kg and 3. 0- 10 μg/kg, respectively. Finally, the analysis system was used for the analysis of real samples and compared with solid phase extrac- tion. The recoveries of OPPs in different vegetable samples ranged from 80.2% to 122. 6%, and the relative standard deviations （RS- Ds） ranged from 1. 6% to 12. 1%. The research provided a highly efficient, accurate, and sensitive quantitative analysis method for the rapid determination of OPPs in vegetables, which is notably important for maintaining vegetable safety.