Chlorpyrifos-methyl Separation Using Obelisc and Primesep Columns

Chlorpyrifos and Chlorpyrifos-methyl are amongst the most widely used pesticides. Chlorpyrifos is considered a target pesticide by the EURL (European Union Reference Laboratory) for the EURL-CF9 and Obelisc R and Primesep B2 were used to separate chlorpyrifos-methyl and its impurities using a single multiresidue method, which can be used for many pesticides. Obelisc R contains embedded ionic and hydrophobic groups which can assist in fine tuning separations, while Primesep B2 contains embedded basic ion-pairing groups. Method is LC/MS compatible and can be used as a general approach for analyzing organophosphate pesticides.