Phosphamidon Analysis Using Obelisc and Primesep Mixed-Mode HPLC Columns

 

Phosphamidon is an organophosphate insecticide commercially available as 70% Z-isomer and 30% E-isomer. It is highly toxic to mammals, and is classified by the World Health Organization to be extremely hazardous (Ia), with an oral lethal dose of less than 5mg/kg of bodyweight. The EURL included phosphamidon as a target pesticide for the EUPT-CF9. Primesep B2 and Obelisc R were used to retain phosphamidon and separate it from impurities. Primesep B2 contains embedded basic ion-pairing groups and Obelisc R contains embedded ionic and hydrophobic groups which can assist in fine tuning separations. Method is LC/MS compatible and can be used as a general approach for analyzing phosphamidon, other organophosphate insecticides, and dozens of other pesticides.