气相色谱／质谱法测定猪肉中莱克多巴胺回收率低的原因分析

摘要

农业部958号公告－4－2007中给出了检测猪肉中莱克多巴胺残留量的气相色谱－质谱法，但在做加标回收实验时（向5 g样品中添加200 ng莱克多巴胺标准物质），其平均回收率仅为50％左右，回收率较低。在本实验室技术水平基础上，对影响回收率的关键步骤进行分析，找出回收率低的原因。%The method of determination of ractopamine residues in pork by gas chromatography-mass spectrometry was given in the 958-4-2007 announcement of Ministry of Agriculture.The average recovery was only 50%when spiked 200 ng ractopamine in 5 g samples.Based on the technical lever in our laboratory , the reason of low recovery was found by analysis of the key step of impact on recovery.