气相色谱-串联质谱法测定柑橘中苯醚甲环唑的不确定度评定

[目的] 对气相色谱-串联质谱法测定柑橘中苯醚甲环唑农药残留进行不确定度评定。[方法] 运用气相色谱-串联质谱法对柑橘中苯醚甲环唑残留量进行测定,建立数学模型, 分析测定过程的主要不确定度来源, 对各个分量进行评估。[结果] 测量不确定度主要来源于前处理方法提取和净化产生的回收率差异、标准溶液配制和目标物色谱峰面积测定误差。当苯醚甲环唑的残留量为 0.047 mg/kg 时, 扩展不确定度为 0.003 mg/kg (P=95%, k=2)。[结论] 该方法适用于气相色谱-串联质谱法测定苯醚甲环唑残留量的不确定度分析, 可为农药残留测量结果的准确性提供科学可靠的依据。

Uncertainty evaluation for the determination of difenoconazole in Citrus by GC-MS/MS

Objective To evaluate the uncertainty for the determination of difenoconazole pesticide residues in Citrus by gas chromatography tandem mass spectrometry (GC-MS/MS). Methods The residue of difenoconazole in Citrus was determined by GC-MS/MS. Through the establishment of mathematical model, the main sources of uncertainty in the measurement process were analyzed, and each component was evaluated. Results The main sources of uncertainty were the difference of recovery ratio between extraction and purification by pretreatment method, the preparation of standard solution and the determination error of chromatographic peak area of target substance. When the residue of difenoconazole was 0.047 mg/kg, the expanded uncertainty was 0.003 mg/kg (P=95%, k=2). Conclusion The method is suitable for the uncertainty analysis of difenoconazole residue by GC-MS/MS, and can provide scientific and reliable basis for the accuracy of pesticide residue measurement results.