分散固相萃取-分散液液微萃取/高效液相色谱法测定西瓜中氟唑菌酰羟胺残留

摘要

A high performance liquid chromatography method for the determination of pydiflumetofen residues in watermelon was developed using dispersive solid-phase extraction and dispersive liquid-liquid microextraction as sample preparation methods.The samples were extracted with acetonitrile and water solution,purified with primary secondary amine as sorbents,and concentrated into 1,1,2,2-tetrachloroethane by dispersive liquid-liquid microextraction.The extracts were analyzed by high performance liquid chromatography.The conditions affecting the purification efficiency of the dispersed solid phase extraction,including the extraction solvent and the type of adsorbent were optimized.Factors affecting the extraction efficiency such as type and volume of extraction solvent,volume of dispersive solvent and salt concentration,were investigated.The results indicated that the calibration curves for the analytes were linear in the concentration range of 0.01-5 mg/L with the correlation coefficients of 0.999 9.The limits of quantification(S/N =10) were 0.01 mg/kg.The mean recoveries at three concentration levels of 0.01,0.1,1 mg/kg were in the range of 89.2％-94.5％ with the relative standard deviations below 8.7％.With the advantages of simplicity,high efficiency and sensitivity,the proposed method was applicable for the analysis of pydiflumetofen residues in watermelon samples.%采用分散固相萃取和分散液液微萃取联用的方法,建立了高效液相色谱快速检测西瓜中氟唑菌酰羟胺残留的分析方法.使用乙腈和水混合溶液作为萃取溶剂,经N-丙基-乙二胺硅烷(PSA)固相萃取吸附剂净化提取液,分散液液微萃取将目标物富集到1,1,2,2-四氯乙烷溶剂中,采用高效液相色谱进行分析.考察了萃取溶剂的种类与体积、分散剂体积及盐浓度等因素对分散液液微萃取萃取效率的影响.结果表明:分析物的质量浓度在0.01 ～5 mg/L范围内与峰面积的线性关系良好,相关系数(r)为0.9999,定量下限(S/N=10)为0.01 mg/kg.加标水平为0.01、0.1、1 mg/kg时,平均回收率为89.2％ ～ 94.5％,相对标准偏差(n=5)为3.0％～8.7％.该方法简单、高效、灵敏度高,适用于西瓜中氟唑菌酰羟胺的残留检测.