Determination of glufosinate ammonium and its metabolite (AE F064619 and AE F061517) residues in water by gas chromatography with tandem mass spectrometry after ion exchange cleanup and derivatization

An analytical method for the determination of glufosinate ammonium and its principal metabolites, AE F064619 and AE F061517, in water of two different hardnesses (5 and 30 DH, French hardness) has been developed and validated . Samples were spiked at different levels (0.05 and 0.5 mug/L) and were pur ified by column chromatography on ion-exchange resins. After derivatization with glacial acetic acid and trimethylarthoacetate mixture, the derivative s were quantified by using capillary gas chromatography with an ion-trap ta ndem mass spectrometric detector. Analytical conditions for MS/MS detection were optimized, and the quantification was carried out on the areas of the most representative ions. The limit of quantification was validated at 0.0 5 mug/L for each compound. The mean recovery value and the relative standar d deviation (n = 20) were 92.0% and 17.8% for glufosinate ammonium, 90.2% a nd 15.8% for AE F064619, and 89.7% and 12.7% for AE F061517.