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The preconcentration of aqueous solutions containing atrazine degradation products was investigated using solid-phase extraction on octadecyl and cation-exchanger silica phases. The retention and elution steps were studied and evaluated separately in order to define and optimize the critical experimental parameters involved. A strategy which combines sequentially both phases is proposed to fractionate compounds into two groups of increasing polarities: firstly, the native pesticide, hydroxyatrazine and most chlorotriazines on octadecyl support, and secondly monodealkylated hydroxytriazines, ammeline and ammelide on cation-exchanger. This tandem procedure was successfully applied for analysing and quantifying atrazine ozonation products and its efficiency demonstrated using [U-ring 14C]-labelled atrazine experiments.

HPLC combined with electrospray ionization MS (LC–ESI-MS) was used for the identification of isoflavonoids and their glycosides in extracts from white lupin (Lupinus albus) tissues. The applicability of LC–ESI-MS for the simultaneous analysis of secondary metabolites of different polarities (free aglycones and their glycosides) is demonstrated. For optimization of the chromatographic and MS conditions, genistin (genistein 7-O-β-glucoside) and rutin [quercetin 3-O-β-(6″-O-α-rhamnosyl glucoside)] were used as standards. The detection limit for the analysis of genistin by HPLC was determined to be 20 ng (ca. 50 pmol). The analytical conditions established were employed to analyse isoflavonoids and their glycosidic conjugates obtained from lupin root extracts by solid phase extraction. Four glycosides and seven isoflavonoid aglycones were detected in the analysed samples. Copyright © 1999 John Wiley & Sons, Ltd.

The ability of liquid chromatography combined with positive-ion low-collision-energy tandem mass spectrometry for screening and characterization of atrazine metabolites in aqueous solutions is examined. The strategy used was defined after investigations on the structure and origin of the main daughter ions through experiments done by desorption chemical ionization with NH3 or ND3 as reagent gas. Following this, a three-step procedure was proposed which included parent-ion spectra based on [XCNC(NH)NH2]+ (with X Cl or OH) ions apparently formed via ion-dipole complexes and found to be highly diagnostic for chlorotriazines and hydroxytriazines respectively.