SCREENING AND CHARACTERIZATION OF ATRAZINE METABOLITES BY LIQUID-CHROMATOGRAPHY TANDEM MASS-SPECTROMETRY

The ability of liquid chromatography combined with positive-ion low-co llision-energy tandem mass spectrometry for screening and characteriza tion of atrazine metabolites in aqueous solutions is examined. The str ategy used was defined after investigations on the structure and origi n of the main daughter ions through experiments done by desorption che mical ionization with NH3 or ND3 as reagent gas. Following this, a thr ee-step procedure was proposed which included parent-ion spectra based on [XC=N-C(=NH)NH2](+) (with X=Cl or OH) ions apparently formed via i on-dipole complexes and found to be highly diagnostic for chlorotriazi nes and hydroxytriazines respectively.