摘要:测定三七中乐果农药残留量。样品添加农药标准品后经超声提取，加入无水硫酸钠，离心分离。将提取液转移至旋转蒸发瓶中,浓缩后用装填无水硫酸钠、硅藻土、弗罗里硅土的层析柱层析分离,用丙酮预淋洗层析柱后,倒入浓缩液,用丙酮洗脱,洗脱液于旋转蒸发仪减压浓缩后, 采用气相色谱仪分析被测样品中农药乐果残留。由于条件选择的原因，未能从三七中检测出有的乐果农药残留。通过实验我认为，加大样品用量，改变净化柱成分，能使分离效果更好，从而符合农药残留分析要求。　

关键词：三七；乐果；农药残留；农残分析

ABSTRACT:Determination of dimethoate’s pesticide residues in pseudo-ginseng. Add pesticide standard product samples after ultrasonic extraction, join sodium sulfate, centrifugal separation . And extracting solution transferred to rotate evaporation bottle. concentrate adds to the chromatography column with sodium sulfate, diatomite and florida silica dust to chromatography separation.Advance with acetone non-contaminated chromatography column, pour into concentrate. Use acetone elution , eluent concentrated by a rotating decompression evaporation instrument. Through the experiment, increase the sample dosage,changing purifying column composition. I think it can make the separation effect is better. Thus comply with requirements of analysis of pesticide residues.　

Key words: Pseudo-ginseng;Dimethoate; Pesticides;Pesticide residues analysis