School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road Shenhe District, 110016, Shenyang, Liaoning Province, China.
School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road Shenhe District, 110016, Shenyang, Liaoning Province, China.
Chemosphere. 2018 Aug;204:210-219. doi: 10.1016/j.chemosphere.2018.03.204. Epub 2018 Apr 3.
A rapid and sensitive multi-residue method was developed for the simultaneous quantification of eight chiral pesticides (including diniconazole, metalaxyl, paclobutrazol, epoxiconazole, myclobutanil, hexaconazole, napropamide and isocarbophos) at enantiomeric levels in environmental soils and sediments using chiral liquid chromatography-tandem mass spectrometry based on a combined pretreatment of matrix solid-phase dispersion and dispersive liquid-liquid microextraction (MSPD-DLLME). Under optimized conditions, 0.1 g of solid sample was dispersed with 0.4 g of C18-bonded silica sorbent, and 3 mL of methanol was used for eluting the analytes. The collected eluant was dried and then further purified by DLLME with 550 μL of dichloromethane and 960 μL of acetonitrile as extraction and disperser solvent, respectively. The established method was validated and found to be linear, precise, and accurate over the concentration range of 2-500 ng g for epoxiconazole, paclobutrazol and metalaxyl and 4-500 ng g for isocarbophos, hexaconazole, myclobutanil, diniconazole and napropamide. Recoveries of sixteen enantiomers varied from 87.0 to 104.1% and the relative standard deviations (RSD) were less than 10.1%. Method detection and quantification limits (MDLs and MQLs) varied from 0.22 to 1.54 ng g and from 0.91 to 4.00 ng g, respectively. Finally, the method was successfully applied to analyze the enantiomeric composition of the eight chiral pesticides in environmental solid matrices, which will help better understand the behavior of individual enantiomer and make accurate risk assessment on the ecosystem.
建立了一种基于基质固相分散和分散液液微萃取（MSPD-DLLME）联合前处理的手性液相色谱-串联质谱法，用于同时检测环境土壤和沉积物中八种手性农药（包括烯唑醇、精甲霜灵、戊唑醇、环氧氯丙烷、咪鲜胺、己唑醇、萘普胺和异恶草松）的对映体残留。在优化条件下，0.1g 固体样品用 0.4g C18 键合硅胶分散剂分散，用 3mL 甲醇洗脱分析物。收集的洗脱液干燥后，进一步用 DLLME 纯化，用 550μL 二氯甲烷和 960μL 乙腈分别作为萃取和分散溶剂。建立的方法经过验证，发现其在环氧氯丙烷、戊唑醇和精甲霜灵的浓度范围为 2-500ng·g，异恶草松、己唑醇、咪鲜胺、烯唑醇和萘普胺的浓度范围为 4-500ng·g 时呈线性、精密和准确。十六种对映体的回收率在 87.0%到 104.1%之间，相对标准偏差（RSD）小于 10.1%。方法检测限和定量限（MDLs 和 MQLs）分别为 0.22-1.54ng·g 和 0.91-4.00ng·g。最后，该方法成功应用于分析环境固体基质中八种手性农药的对映体组成，这将有助于更好地了解单个对映体的行为，并对生态系统进行准确的风险评估。
