QuEChERS-超高效液相色谱-串联质谱法测定紫花地丁中82种农药多残留

采用超高效液相色谱-串联质谱法(UPLC-MS/MS)，优选最佳QuEChERS样品前处理方法，建立了紫花地丁Viola yedoensis中82种农药残留的快速筛查和定量检测方法。通过正交试验设计9种组合，研究4种不同吸附剂(PSA、C₁₈、GCB和SiO₂)对紫花地丁净化效果的影响。紫花地丁样品分别经800 mg PSA、3 200 mg C₁₈、1 600 mg GCB和1 600 mg SiO₂提取与净化，采用phenomenex DOD-4475-AN C₁₈色谱柱分离，0.1%甲酸(含10 mmol/L甲酸铵)-乙腈混合溶液进行梯度洗脱，标准曲线法定量。结果表明:82种农药在相应的线性范围内，色谱响应值与对应的质量浓度间均呈良好的线性关系(r ≥ 0.99)，检出限(LOD)均在0.3~5 μg/kg之间，定量限(LOQ)均在1~20 μg/kg之间。在0.02、0.05和0.1 mg/kg 3个添加水平下，大多数农药的平均回收率介于70%~111%之间，相对标准偏差(RSD，n = 6)小于19%。该方法操作简单、准确、高效，可满足紫花地丁中82种农药残留同时检测的要求。

Simultaneous determination of 82 pesticides in Viola yedoensis Makino by QuEChERS-ultra high performance liquid chromatography-tandem mass spectrometry

Rapid screening and quantitative determination of 82 pesticides with QuEChERS were achieved by ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In the orthogonal experiments, 9 combinations were designed to investigate the effect of 4 different adsorbents (PSA, C₁₈, GCB and SiO₂) on the purification performance of Viola yedoensis Makino.V. yedoensis samples were pretreated by PSA 800 mg, C₁₈ 3 200 mg, GCB 1 600 mg and SiO₂ 1 600 mg. The chromatographic separation of 82 pesticides was achieved by phenmenex DOD-4475-AN C₁₈ column using acetonitrile/water (0.1% formic acid and 10 mmol/L ammonium formate) in the gradient elution mode. Standard curve method was utilized for the quantitation. The results indicated that 82 pesticides showed good linear relationship within the corresponding concentration ranges (r≥0.99). The detection limits (LOD) were 0.3-5 μg/kg and the limits of quantitation (LOQ) were 1-20 μg/kg. Under spiked levels of 0.02, 0.05 and 0.1 mg/kg, the average recoveries of most pesticides were between 70%-111%, and the relative standard deviations (RSD, n = 6) were less than 19%. This method is simple, accurate and efficient, which can meet the requirements for the detection of 82 pesticide residues in V. yedoensis samples.