超高效液相色谱-串联质谱法测定丁氟螨酯和联苯肼酯及2种代谢物在柑橘中的残留消解动态

Residues and dissipation dynamics of cyflumetofen and bifenazate and 2 kinds of metabolites in Citrus by ultra performance liquid chromatography-tandem mass spectrometry

中文关键词:  柑橘  丁氟螨酯  联苯肼酯  消解动态

英文关键词:cyflumetofen  bifenazate  degradation dynamics

中文摘要:

      目的 采用超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定柑橘中丁氟螨酯和联苯肼酯及代谢产物2-三氟甲基苯甲酸和联苯肼酯-二氮烯的残留量，评价其在柑橘中的残留消解。方法 样品前处理采用QuEChERS方法，经酸化乙腈提取，加NaCl盐析，经无水MgSO4除水和石墨化炭黑净化，采用UPLC-MS/MS检测，基质匹配外标法定量。结果 4种目标物在一定质量浓度范围内具有良好的线性关系(r≥0.9994)。在0.01、0.02、0.70、5.00 mg/kg添加水平下，平均回收率为76%~101%，相对标准偏差为0.6%～15.2%。残留消解试验结果显示，柑橘中丁氟螨酯残留检出成分为其母体；而联苯肼酯与联苯肼酯二氮烯均有残留，联苯肼酯转换成联苯肼酯二氮烯非常迅速。不同试验点残留水平和消解速率不同，这不仅受到施用时间的影响，也受环境因子的影响。丁氟螨酯在湖北、广西和湖南试验点的全果中半衰期分别为13.9、28.8和20.0 d；联苯肼酯（总残留量）在广西试验点的全果中半衰期为20.7 d。结论 在推荐最高剂量下，丁氟螨酯和联苯肼酯消解迅速，本研究中各采样时间点的残留量均未超过MRL值。

英文摘要:

      Objective To determine the residues of cyflumetofen and bifenazate, along with their metabolites 2-trifluoromethylbenzoic acid and biphenylhydrazide diazene in citrus by ultra High-performance liquid chromatography tandem mass spectrometric (UPLC-MS/MS), and to evaluate the residues dissipation in citrus. Methods QuEChERS method was utilized for the sample preparation. The samples were extracted with acidified acetonitrile, followed by salting out with NaCl. The extracts were then dehydrated with anhydrous MgSO4 and purified using graphitized carbon black (GCB). Detection was conducted with UPLC-MS/MS, and quantification was achieved through a matrix-matching external standard method. Results The four target substances exhibited a strong linear relationship (r ≥0.9994)within a specific mass concentration range. At spiked concentration levels of 0.01 0.02, 0.70 and 5.00 mg/kg, the average recoveries ranged from 76%~101% with the relative standard deviation (RSD) of 0.6%~15.2%. The results of the residue digestion test show that the detected residue of cyflumidamide in citrus is its parent compound. Both bifenazate and biphenylhydrazine diazene were found to have residues, with the conversion from bifenazate to biphenylhydrazide diazene occurring rapidly. Variability in residue levels and degradation rates across different experimental sites is influenced not only by the timing of application but also by environmental factors. The half-lives of cyflumetofen in whole fruit at experimental sites located in Hubei, Guangxi, and Hunan were 13.9, 28.8, and 20.0 days, respectively. The half-life of total bifenazate residues in whole fruit at the site of Guangxi was 20.7 days. Conclusion At the recommended maximum dose, the degradation of cyflumetofen and bifenazate was rapid, and the residual levels at each sampling time point in this experiment did not exceed the MRL value.