The Development Of Five Kinds Of Pesticide Reference Material

In this paper, acetochlor, dimethomorph, malathion and hexythiazoxTC were purified by using purification methods like columnchromatography and recrystallization. Through many experiments, theoptimization method of purification for acetochlor, dimethomorph,hexythiazox, malathion was developed. In accordance with the purificationmethods, the value of the reference material of acetochlor can be promotedfrom96%to99.7%. The value of the reference material of malathion canbe promoted from96%to99.3%. The value of the reference material ofdimethomorph can be promoted from97.5%to99.5%. The value of thereference material of hexythiazox can be promoted from97.5%to99.7%.The results can meet requirements of development of national firstreference materials. According to repeated the experiment, a lot of purifiedproducts of acetochlor, Dimethomorph, malathion and hexythiazox have begot. Those products can be use for developing the standard material.Through optimization of the parameters of GC-MS, a method wasdeveloped for the determination of malathion, acetochlor, dimethomorph and hexythiazox. Combination the results of FTIR, the qualitativeconfirmation were made for the5standard materials what was developedin the paper. Through the selection of gas chromatographic detector andthe optimization of oven temperature, A GC method was developed for thequantitative determination of acetochlor, dimethomorph, vinclozolin andmalathion. Through the selection of detection wavelength and theoptimization of mobile phase ratio, A HPLC method was developed forthe quantitative determination of acetochlor, dimethomorph, vinclozolin,hexythiazox and malathion.Two methods which with different detecting principle were used forquantitative determination of acetochlor, dimethomorph, vinclozolin andmalathion. The result: acetochlor (GC99.71, HPLC99.89), dimethomorph(GC99.54, HPLC99.54), malathion (GC99.19, HPLC99.07), vinclozolin(GC99.12, HPLC99.12). The value of the reference material ofhexythiazox was evaluated by different laboratories. The result:hexythiazox (HPLC99.81). In the past year, the homogeneity and stabilityof the five standard reference materials was tasted. The uncertainty of the5reference materials was analysed. The final results are that: the purity ofacetochlor is99.80%, the relative expanded uncertainty is0.38%. Thepurity of dimethomorph is99.54%, the relative expanded uncertainty is0.48%. The purity of malathion is99.13%, the relative expandeduncertainty is0.56%. The purity of hexythiazox is99.81%, the relative expanded uncertainty is0.39%. The purity of vinclozolin is99.12%, therelative expanded uncertainty is0.98%.A HPLC method was developed for the quantitative determination ofvinclozolin dy using the standard materials of vinclozolin. The blank in theHPLC analysis method of vinclozolin TC was filled. It can providereference for the application of vinclozolin in the daily work.