Application of directly coupled HPLC-NMR-MS/MS to the identification of metabolites of 5-trifluoromethylpyridone (2-hydroxy-5-trifluoromethylpyridine) in hydroponically grown plants

Directly coupled HPLC-NMR-MS was used to characterize two major metabolites of 5-trifluoro-methylpyridone (2-hydroxy-5-trifluoromethylpyridine), a mod el compound for herbicides, after it had been dosed into hydroponically gro wn maize plants. The combination of NMR and MS data allowed the identificat ion of both of these metabolites, namely, the N-glucoside and O-malonylgluc oside conjugates of the parent pyridone. This work demonstrates the efficie ncy and the potential application of HPLC-NMR-MS to the investigation of th e metabolism of agrochemicals. The work also indicates that combination of the use of hydroponically grown plants and directly coupled HPLC-NMR-MS all ows rapid identification of metabolites with little sample preparation.