果蔬中嘧菌酯残留量的气相色谱分析研究

基于气相色谱分析,建立了葡萄和甘蓝等水果蔬菜中嘧菌酯残留量的2种快速检测方法.样品使用乙酸乙酯-环己烷(50-50)为溶剂进行超声波萃取,采用GC/NDP和GC/μECD检测法测定.在检测过程中不存在干扰峰,样品不需净化.用两种检测方法互相确证定性和定量结果,结果表明两种方法嘧菌酯回收率在80%-105%,最低检出浓度分别为0.005 mg/kg和0.002 mg/kg.经配对t检验统计分析,两种方法定量结果间无显著性差异.

Studies on determination methods of azoxystrobin residue in fruits and vegetables by gas chromatography

Two methods of gas chromatography(GC) with nitrogen/phosphorous detector(NPD) and microcell electron capture detector(μECD) were developed for quick-determinating of azoxystronbin(AZX) residue in grape,cabbage and other fruits and vegetables.Taking ethyl acetate-cyclohexane as the solvents,the test samples were extracted by means of ultrasonic oscillation treatment with ultrasonator,and then were directly determined by GC/NDP and GC/μECD.Depuration of the samples would be unnecessary because no interference peak was displayed in the chromatograms as the results of determinating.The qualitative and quantitative results obtained by two methods were compared and validated with each other.Recovery percentage of azoxystronbin from the fortified samples by both detectors ranged from 85.7 % to 110.5 %,and the minimum detection limit of the concentration levels were 0.001 mg/kg and 0.002 mg/kg respectively.The correlation coefficients of standard curves were 0.9997 for μEC-detector and for NP-detector,respectively.According to statistical analysis of the experimental data by paired samples t-test,there was no significant difference between NP-detector and μEC-detector for the determination of azoxystrobin residue.