植物性样品中二硫代氨基甲酸酯类农药残留检测方法比较研究

Comparative study on determination of dithiocarbamates residue in vegetative samples

目的建立准确且适用于植物性样品中二硫代氨基甲酸酯类(DTCs)农药残留的检测方法并进行比较。方法研究检测植物性样品中DTCs农药残留的气相色谱-火焰光度检测器法(GC-FPD)和气相色谱质谱法(GC-MS)的特异性、灵敏度、准确度、精密度和转化率并进行比较,并对2015~2021年镇江市售104份植物性样本中DTCs农药残留监测结果进行分析。结果GC-MS法检出限更低(0.003mg·kg^(-1)),GC-FPD法和GC-MS法在检测浓度范围内线性关系良好(r>0.999),在低、中、高3个加标水平下的加标回收率为87.6%~103.4%,相对标准偏差(RSD)为5.6%~8.9%,转化率良好且稳定;104份样品中有10类29份样品检出,检出率为27.9%,检出值为0.030~1.54mg·kg^(-1)。结论GC-FPD法和GC-MS法准确度高、精密度好,均满足植物性样品中DTCs农药残留的检测需求,GC-FPD法操作简便、快捷,而GC-MS法灵敏度更高,具有更佳的抗干扰能力。

OBJECTIVES Comparing and studying accurate and applicable detection method of dithiocarbamates(DTCs)residue in vegetative samples.METHODS The specificity,sensitivity,accuracy,precision and inversion rate of gas chromatography-flame photometric detector(GC-FPD)and gas chromatography mass spectrometry(GC-MS)for the determination of DTCs residue in vegetative samples were investigated and compared,and the results of the pesticide residue monitoring of DTCs in 104 vegetative samples sold in Zhenjiang City were analyzed during the period from 2015 to 2021.RESULTS The limit of quantification(LOQ)of method by GC-MS was lower(0.003mg·kg^(-1)).In the range of detection concentrations,the GC-FPD and GC-MS method had good linear relationships(r>0.999).The recoveries were 87.6%~103.4%with relative standard deviations of 5.6%~8.9%.The inversion rates were good and stable.DTCs were detected in 29 vegetable samples from ten classes with the detection rate of 27.9%and with the range of 0.030~1.54mg·kg^(-1).CONCLUSIONS The GC-FPD and GC-MS method had high accuracy and good precision,which could meet the detection of DTCs residue in vegetative samples.GC-FPD method was simple and faster,and yet GC-MS method was more sensitively which had better anti-interference ability.