大米中敌稗残留量测定方法的研究

Study on the determination of propanil residues in rice

为贯彻实施敌稗农药最大残留限量国家标准 ,建立大米中敌稗残留量测定方法 ,试样用丙酮提取 ,石油醚萃取和弗罗里硅土净化 ,乙醚 -正己烷 (1∶1)淋洗。净化液用配有电子捕获检测器的气相色谱仪测定 ,外标法定量。方法最低检测浓度 4× 10 -4mg kg ,敌稗浓度在 0 2 0～ 2 0 0mg kg范围内 ,平均回收率为 89 7%～ 90 7% ,相对标准偏差为 4 4 6 %～ 5 2 1% ,符合农药残留分析的要求。

The method for determination of propanil residues in rice is established to implement the MRL of it.The samples were extracted with acetone and the extraction were extracted with benzinum and purificated again.Then the solution is cleaned up through Florisil column,rinse with ethyl ether:n\|hexane (1∶1).The purified solution is detected by GC with electron capture detector and the residue content is determined quantitatively by external standard method.The limit of determination of this method is 4×10 -4 mg/kg,according to the experimental data,when the concentration of propanil is in the range of 0 20～2 00 mg/kg,the recovery is 89 7%～90 7%, RSD is 4 46%～5 21%.The results of test have met the requirement of pesticide residue analysis. Author's address: Ji Yuling,Nanjing Agricultural University,Nanjing 210095,Jiangsu provcince, PRC.