Department of Applied Chemistry, China Agricultural University, Beijing, People's Republic of China.
Chirality. 2013 Sep;25(9):567-74. doi: 10.1002/chir.22172. Epub 2013 Jun 18.
A rapid, simple, reliable, and environment-friendly method for the residue analysis of the enantiomers of four chiral fungicides including hexaconazole, triadimefon, tebuconazole, and penconazole in water samples was developed by dispersive liquid-liquid microextraction (DLLME) pretreatment followed by chiral high-performance liquid chromatography (HPLC)-DAD detection. The enantiomers were separated on a Chiralpak IC column by HPLC applying n-hexane or petroleum ether as mobile phase and ethanol or isopropanol as modifier. The influences of mobile phase composition and temperature on the resolution were investigated and most of the enantiomers could be completely separated in 20 min under optimized conditions. The thermodynamic parameters indicated that the separation was enthalpy-driven. The elution orders were detected by both circular dichroism detector (CD) and optical rotatory dispersion detector (ORD). Parameters affecting the DLLME performance for pretreatment of the chiral fungicides residue in water samples, such as the extraction and dispersive solvents and their volume, were studied and optimized. Under the optimum microextraction condition the enrichment factors were over 121 and the linearities were 30-1500 µg L(-1) with the correlation coefficients (R(2)) over 0.9988 and the recoveries were between 88.7% and 103.7% at the spiking levels of 0.5, 0.25, and 0.05 mg L(-1) (for each enantiomer) with relative standard deviations varying from 1.38% to 6.70% (n = 6) The limits of detection (LODs) ranged from 8.5 to 29.0 µg L(-1) (S/N = 3).
建立了一种快速、简单、可靠且环境友好的方法，用于通过分散液液微萃取（DLLME）预处理，然后通过手性高效液相色谱（HPLC）-DAD 检测分析水样中包括己唑醇、三唑酮、戊唑醇和烯唑醇在内的四种手性杀菌剂的对映体残留。在 HPLC 上，通过手性固定相 Chiralpak IC 柱分离对映体，以正己烷或石油醚为流动相，乙醇或异丙醇为改性剂。考察了流动相组成和温度对分离度的影响，在优化条件下，大多数对映体可在 20 分钟内完全分离。热力学参数表明，分离是焓驱动的。通过圆二色检测器（CD）和旋光色散检测器（ORD）均检测到洗脱顺序。研究并优化了影响水样中手性杀菌剂残留的 DLLME 性能的参数，如萃取和分散溶剂及其体积。在最佳微萃取条件下，富集因子大于 121，线性范围为 30-1500 µg L(-1)，相关系数（R(2)）大于 0.9988，回收率在 0.5、0.25 和 0.05 mg L(-1)（每个对映体）的加标水平之间为 88.7%-103.7%，相对标准偏差（RSD）在 1.38%-6.70%（n = 6）之间。检测限（LOD）范围为 8.5-29.0 µg L(-1)（S/N = 3）。
