Research Of Quick Inspective Technique Of Pesticide Multi-residue In Vegetables And Fruits

The influences of different chromatographeric columns and heating temperature tothe retention time and the influence of different elution solvents and chromatographericcolumns to CVs of pesticide were discussed in this article. In addition, a rapid analyticalmethod on determination of pesticide multi-residues in fruits and vegetables is presentedtoo. In this method, consulting the method of CDFA (California Department of Food andAgriculture of USA), the author has studied the analytical technique of four type ofpesticide (organic phosphorus, organic chlorine and carbamate etc) in fruits andvegetables that have great value in China, with GC and HPLC. The experiment resultsshow: Heating temperature has little effect to the order of retention time, while the columnshave a great influence to the retention time. Different pesticides may not be separated inone chromatographeric column, but they can be separated in another chromatographericcolumn. Consequently, using double columns for detection can be more accurate than theone column. On the occasions of using solid-phase extraction (SPE) for the sample purificationand concentration, the elution solvents and chromatographer columns have a great effecton the experimental results. By designing the different combination of elution solventsand chromatographeric columns, the best approach is using 20ml n-hexane whichcontains10% acetone and employment of the Florisil Columns. The CVs of pesticide(cypermethrin, cyfluthrin and bifenthrinin) is 80-120%. Of 60 pesticides analyzed, recoveries are between 70-120%, the compounds showedless than 20% CVs and the minimum detection limits is within the range of the maximumresidue limits. The result is suitable for the analytical method of pesticide multi-residues.Comparing with traditional analytical methods, this method has much excellence. Forexample, it can save solvent, the time of determination (it will cost 2 hours or so toanalyze a sample) and can inspect a lot of pesticide (27 kinds of organic phosphorus,25kinds of organic chlorine and 8 kinds of carbamate) at the same time.