超高效合相色谱法对6种三唑类农药对映体的拆分及其在黄瓜中的残留分析

采用超高效合相色谱法（UPC²）拆分三唑酮、三唑醇、己唑醇、戊唑醇、联苯三唑醇、腈菌唑等6种三唑类农药对映体，并测定了黄瓜中6种三唑类农药对映体的残留量。样品经乙腈均质提取，石墨化炭黑（GCB）、自制弗罗里硅土柱和QuEChERS试剂依次净化后，Acquity Trefoil AMY1手性色谱柱分离，以超临界二氧化碳-甲醇等助溶剂为流动相进行梯度洗脱，外标法定量。方法定量限（S/N>10）均为0.1 mg/kg，在黄瓜中分别添加0.1、0.2、0.5 mg/kg 3个水平的三唑类农药对映体，其回收率为65.1%~116%，相对标准偏差（n=6）为1.0%~9.6%。该方法实现了对6种三唑类农药16种对映体的拆分及其在黄瓜基质中的残留测定，可为手性农药开发、使用及相关法规的制定提供科学支撑。

Chiral separation of six triazole pesticide enantiomers by ultra-performance convergence chromatography and residue determination in cucumber

The separation of six triazole pesticide enantiomers (TPEs) by ultra-performance convergence chromatography (UPC²) was attempted, and residue analytical methods for these TPEs in cucumber were established. The triazole pesticides were triadimefon, triadimenol, hexaconazole, tebuconazole, bitertanol, and myclobutanil. The sample was extracted with acetonitrile and cleaned up using graphitized carbon black (GCB), a Florisil-phase extraction column, and the QuEChERS method. The treated extract was separated on an Acquity Terifoil AMY1 chromatographic column, with gradient elution using a mixture of supercritical CO₂ and methanol or ethanol-isopropanol as the mobile phase. The residues of the six TPEs were quantified by the external standard method. The limits of quantitation (S/N>10) of these TPEs in cucumber were 0.1 mg/kg. The recoveries of the TPEs in cucumber at three spiked levels of 0.1, 0.2, and 0.5 mg/kg ranged from 65.1% to 116% with relative standard deviations (RSDs) of 1.0%-9.6%. The developed method facilitated the enantioseparation of the six TPEs and the accurate estimation of their residues in the cucumber matrix. This method is expected to play an important role in the production and utilization of chiral pesticides, as well as the establishment of relevant laws and regulations.