气相色谱-质谱法检测菠菜中20种农药残留

GC-MS Detection of 20 Pesticide Residues in Spinach

菠菜样品经过切碎、均质、盐析、乙腈提取后,经PestiCard/NH2柱净化,采用DB-1701色谱柱和MSD检测器进行检测,外标法定量,同时进行20种农药残留的检测.在最佳试验条件下,20种农药在0.01～1.00μg/ml线性良好,相关系数为0.9945～0.9999,样品加标回收率为82.4%～120.5%,相对标准偏差≤10.5%,检出限均低于0.01μg/ml.这表明该方法简便快速、分离度好、定性准确、可以有效排除基质干扰,各项指标均可满足进出口菠菜中多种农药残留同时检测的要求.

An optimized analytical method using gas chromatography-mass spectrometery （GC-MS） has been developed for rapid determination of 20 pesticides residue in fresh spinach,including organo-phosphorus,organochlorines, pyrethroid and triazole. After cutting up, uniforming, salting out, acetonitrile extraction and purification using PestiCard/NH2 column,the spinach samples are detected by HP-5 MS chromatographic column and MSD edtector,then they are quantitated by external standard method. 20 of pesticide residues are simultaneously detected. Under the optimum experimental condition all of 20 pesticides presents a good linearity among a regular concentration range with the correlation coefficient range of 0. 994 5-0. 999 9. The average recovery of samples is in the range of 82.4%-120.5% ,the relative standard deviations are lower than or equal to 10.5 % and the low detection limits are all lower than 0.01 μg/ml. It indicates that the method is simple, fast, accurate, and has a good separation, and can effectively expel matrix interference, so it meets the the requirements of the detection of pesticide residues in fresh import-export spinach.