Development and validation of a fast high-performance liquid chromatography method for the determination of microencapsulated pyrethroid pesticides

The use of microencapsulated pesticides in urban and rural pest control obliges to develop valid analytical methods for both free and microencapsulated pesticide. An analytical procedure for the pesticide quantification by reversed phase-high-performance liquid chromatography (RP-HPLC) based on pesticide extraction from the microcapsules by dissolution of the wall with dimethylacetamide and the quantification of pesticide in the presence of the polymer is proposed. The shell of the Commercial Insecticide Microcapsules is mainly made of polyurea or polyamide. For this reason, cypermethrin loaded polyurea microcapsules are used as model. The proposed analytical procedure is proportional, accurate and precise, in the range from 0.2 to 1.2 μg, using as solvent dimethylacetamide:acetonitrile (5:95). It has been successfully proved for the quantification of microencapsulated pesticide in vegetables.