| Chinese herbal medicine, as a special food, plays an important role in maintenance of health in China, and the requirement of it is on the increase. Now, the cultivation of many Chinese herbal medicines is depended on manpower. Because the pesticides were often applied to reduce loss from insects in cultivation, the Chinese herbal medicines had easy a high risk of contamination of pesticides, and the health of people was disserved. Recently, the study focused mainly on organochlorine, and was less on the other pesticides, which fell short of practical contamination in Chinese herbal medicine.Ephedra Herb and Chinese Wolfherry are important officinal plants in Xinjiang. It was momentous meaning to accelerate exploitation and utilization of Ephedra Herb and Chinese Wolfherry by strengthening study on determination of pesticide residues. In our experimentes, Matrix solid-phase dispersion (MSPD), Ultrasonic extraction-column purge were used to study on simultaneous determination of five pyrethroid pesticides and four organophosphorus pesticides in Ephedra Herb and Chinese Wolfherry from Xinjiang by GC. The factors of influence on pick-up and purge of pesticides were investigated and the parameters of test were optimized. The effects of two means were compared. The main conclusion as follow:1.A method was developed for the determination five pyrethroid pesticides residues in Ephedra Herb and Chinese Wolfherry.In MSPD studies, Florisil was used for sorbent and eluting solvent was ethyl acetate -petroleum ether(1:4,V/V). The eluates were clean enough for GC determination without further cleanup. In three fortified levels(0.50mg/kg,0.25mg/kg and 0.05mg/kg ),the recoveries of five pyrethroid pesticides were in the ranges of 80.7%-105.7% and 80.2%-100.1%,with relative standard deviations of1.6%-9.4% and 2.6%-9.1%,respectively. The limits of detection were between 0.004mg/kg-0.01 mg/kg.In ultrasonic extraction-column purge, acetone-petroleum ether(3:2,V/V)was used for extraction solvents. The extracts was cleaned up with a column filled Florisil and neutral aluminum oxide, and then was determined by GC directly. In three fortified levels, the recoveries of five pyrethroid pesticides were in the ranges of 82.1%-92.3% and 81.2%-93.7%, with relative standard deviations of1.2%-7.8% and 1.9%-6%, respectively.2. A method was investigated for the determination four organophosphorus pesticides residues in Ephedra Herb and Chinese Wolfherry.In MSPD studies, the sorbent was Florisil and the eluting solvent were ethyl acetate and acetone-ethyl acetate ( 1:1,V/V ) , respectively. In three fortified levels(0.70mg/Kg,0.35mg/Kg and 0.07mg/Kg), the recoveries of four organophosphorus pesticides were between 84.5%-98.9% amd 82.4%-93.6%,with relative standard deviations were between 1.3%-5.1% and 2.9%-7.4%,respectively. The limits of detection were between 0.006mg/kg-0.008 mg/kg.In ultrasonic extraction-column purge, acetone was used for extraction solvents. The extracts was cleaned up with a column filled Florisil and neutral aluminum oxide.In three fortified levels,the recoveries of four organophosphorus pesticides were in the ranges of 81.5%-90.7% and 80.4%-85.3%,with relative standard deviations of1.7%-4.2% and 2.9%-4.2%, respectively.The resultes of the two methods revealed that the method of ultrasonic extraction-column purge was cockamamie and consumed a great of deal solvent. MSPD was simple, rapid,selective,and a perfect means in analysis of pesticides residues.
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