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目的:建立三七中7种有机氯农药残留的毛细管气相色谱方法。方法:采用丙酮和石油醚(1∶1)超声波提取,浓硫酸净化,采用GC-ECD,Phenomenex Zebron-2(USA)农残专用毛细管柱检测,外标法计算含量。以添加回收率为指标,重点考察了溶剂总用量、超声波提取总时间、样品颗粒大小等因素对添加回收率的影响。结果:丙酮和石油醚(5∶5)总用量60mL,超声波总时间为31min和样品颗粒大小为100目;方法的线性范围为2.38×10-13~4.76×10-11g,最小检测量为1.4×10-13~2×10-13g;平均添加回收率83.363%~110.13%,RSD为3.15%~7%。结论:建立的方法快速、线性好、精密度优良,适用三七中有机氯残留的测定。
Objective: To establish a method for the determination of seven organochlorine pesticide residues in Radix notoginseng by capillary gas chromatography. Methods: Ultrasonic extraction with acetone and petroleum ether (1: 1) and purification with concentrated sulfuric acid were carried out by GC-ECD and Phenomenex Zebron-2 (USA). Taking the recovery rate as the index, the effects of the total amount of solvent, the total time of ultrasonic extraction, the particle size of the sample and other factors on the recoveries were investigated. Results: The total amount of acetone and petroleum ether (5: 5) was 60mL, the total time of ultrasonic wave was 31min and the particle size of the sample was 100 mesh. The linear range of the method was 2.38 × 10-13 ~ 4.76 × 10-11g with the minimum detection of 1.4 × 10-13 ~ 2 × 10-13g. The average recovery was 83.363% ~ 110.13% with RSD of 3.15% -7%. Conclusion: The established method is rapid, good linearity and good precision. It is suitable for the determination of organochlorine residues in.