【摘要】 研究采用固相萃取-高效液相色谱法测定玉米中吡虫啉的残留。样品中吡虫啉经乙腈提取,采用刚活化后弗罗里硅土对其进一步净化提纯,洗脱液为丙酮;将洗脱液用氮吹浓缩、定容、过滤后,供液相色谱测定;采用安捷伦XDB-C18(250mm×4.6mm)色谱柱,柱温40℃,甲醇-乙腈-水(10∶10∶80)为流动相,检测波长270nm;该方法的检测限为0.2μg/mL,线性范围0.2～5μg/mL,线性相关系数为0.9993,回收率达84.2%。结果表明,该分析方法不仅操作简便,分析周期短,而且方法准确度高,色谱分离效果好。更多还原

【Abstract】 A combination method of SPE and HPLC were used to determine imidacloprid residuals in corn. Imidacloprid was extracted with acetonitrile from the sample and the extraction was further purified with fresh activated Florisil. Acetone was used as eluent. Eluent was concentrated with nitrogen and diluted to volume and filtrated. The chromatographic conditions were: Agilent XDB-C18(250mm×4.6mm) column at 40℃, MeOH/ CH3CN/H2O(10∶10∶80) as mobile phase, UV detector at 270nm. Detection limit of the method was 0.2μg/mL, linear range and linearly dependent coefficient were 0.2～5μg/mL and 0.9993 respectively, average recovery is 84.2%. The result showed that this method is easy to operate, with greatly shortened analytical time, greatly enhanced accuracy, and obviously improved separation results.更多还原