The Method Of Simultaneous Determination With GC-MS For 11 Phosphate Pesticide Residues In Vegetable And Fruit

In this paper,we study on the method for 11 phosphate pesticide residues with gas chromatography - mass spectrum(GC/MS) in vegetable and fruit.The minimum detectable concentration ,recovery rate and relative standard deviation all consistent with the specification of government standard and the standard of Ministry of Agriculture. The accuracy of analysis for sample injection by one time is very high.The color spectrum and the mass spectrum analysis could carry out very effective segregation and analysis for 11 phosphate pesticide residues.Besides the baytex and durshan having partial overlapping ,other organic phosphorus agricultural chemicals could be separated efficiently. Although superficial peak form overlaps, not affected to the accurate quota, because the ion of each compound pesticide selecting is different. The detection limit of various pesticides is different from 0.006mg/kg～0.048mg/kg. In which the smallest is Rogor, achieves 0.006mg/kg, but its detection sensibility is highest; however the detection limit of acephate is 0.048mg/kg, which is the biggest in 11 phosphate pesticide, illustrating its detection sensibility is very low. The detection limit of compound mainly is decided by its respective nature. Using the mixed solution of different proportion of acetone and N-hexane to extract pesticide , actually ,the effectiveness is not well as alone using acetone;the reason mainly is by the polarity of orgnaophosphorus pesticides. The different dosage of eluent will directly influent the recovery rate level of pesticide.Using 8mL dosage, the recovery rate can reach to 98%; increasing the dosage of eluent to 10mL, the recovery rate do not obviously improved; therefore we recognize 8mL is the best dosage used. Overall, the average recovery rate of various pesticide is between 79% and 118% ,which conforms to correlation requirement for pesticide analysis. The coefficient of...