ESTABLISHMENT OF ISOMERIC COMPOSITION OF INSECTICIDAL CYPERMETHRIN SUBSTANCE BY RP-HPLC
The determination of cypermethrin, one of the most sought pyrethroid insecticides having a wide range of activities, by isocratic RP-HPLC is considered. The analysis of substances (technical products) with different content of both the geometrical (cis-, trans-) and optical (zetacypermethrin and alfacypermethrin) isomers of cypermethrin was carried out. Information about the content of the most active forms of cis- allows evaluating the effectiveness of the biological substance based only on RP-HPLC data, which in turn can be a decisive factor in the of the substance assessment supplier / manufacturer or ready commercial products. The optimum concentration range for determining the geometric isomers of cypermethrin in the working solution is from 0.2 to 1.0 mg/ml. The substance detection limit in working solutions/washings is 0.005 mg/ml.