Differential pulse polarographic determination of dicrotophos, crotoxyphos and chlorfenvinphos in grains and soils.

摘要

A differential pulse polarographic method was developed for the quantitative determination of organophosphorus pesticides such as dicrotophos, crotoxyphos and chlorfenvinphos in agricultural formulations in universal buffers of a pH range 2.0-12.0.Grain (rice or wheat) and soil samples that were sprayed with known amounts of the pesticides and left for 2-4 h, were treated with ethanol to facilitate the dissolution of the pesticides. Standard addition and calibration methods were used for the analyses. Recoveries ranged from 96.33 to 99.67%. The lower detection limits were 1.25 X 109, 1.05 X 10-9 and 1.0 X 10-9 M, respectively. It is concluded that the method is simple, rapid, reliable and sensitive, and may therefore be used in insecticidal formulations.