Azinphos-ethyl Analysis on Mixed-Mode HPLC Columns

Azinphos-ethyl is a highly toxic organophosphate insecticide.  Azinphos-ethyl was retained on both Obelisc R and Primesep B2 mixed-mode HPLC columns. Primesep B2 contains embedded basic ion-pairing groups while 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 azinphos-ethyl and other organophosphate insecticides.