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Lauryl methacrylate (LMA)-ester based monolithic columns photo-polymerized using lauroyl peroxide (LPO) as initiator were prepared, and their morphological and CEC properties were studied. The composition of the polymerization mixture (i.e. ratios of monomers/porogenic solvents, 1,4-butanediol/1-propanol and LMA/crosslinker) was optimized. The morphological and chromatographic properties of LMA columns were evaluated by means of SEM pictures and van Deemter plots of PAHs, respectively. The polymerization mixture selected as optimal provided a fast separation of a mixture of PAHs with excellent efficiencies (minimum plate heights of 8.9-11.1 microm). Satisfactory column-to-column (RSD<4.5%) and batch-to-batch reproducibilities (RSD<6.3%) were achieved. The LMA columns photo-polymerized with LPO were compared with those prepared with AIBN. Using PAHs, alkylbenzenes and basic compounds for testing, the columns obtained with LPO gave the best compromise between efficiency, resolution and analysis time.

Technical grade diethylene-triaminepentakis(methylenephosphonic acid) (I), dihexamethylene-triaminepentakis(methylenephosphonic acid) (II), ethylene-diaminetetrakis(methylenephosphonic acid) (III), hexamethylene-diaminetetrakis(methylenephosphonic acid) (IV), amino-tris(methylenephosphonic acid) (V), hydroxyethyl-aminobis(methylenephosphonic acid) (VI), 1-hydroxyethylidene-1,1-diphosphonic acid (VII), and 2-phosphonobutane-1,2,4-tricarboxylic acid (VIII) were characterized by ion trap mass spectrometry with electrospray ionization (ESI-ITMS). Using the negative ion mode and acid and alkaline media, peak series corresponding to the nominal compounds and to impurities with a lower number of phosphonate groups were distinguished in I-V. Each series was constituted by [M - nH + (n - 1)Na](-) peaks and peaks produced from them by losses of water, H(3)PO(3)(or water plus HPO(2)), and combined losses. For each [M - nH + (n - 1)Na](-) peak, the number of losses coincided with the number of phosphonate groups not bound to sodium ions minus one (the group bearing the charge). Owing to the hydroxyethyl group, the spectrum of VI was dominated by the formation of intermolecular esters, with both losses and gains of water according to [nM - H +/- mH(2)O](-). A series of [M - nH + (n - 1)Na](-) peaks were observed for VII and VIII, showing in the latter case that the carboxylate groups may also form adducts with sodium ions. Losses of water and H(3)PO(3)were observed in VII, whereas losses of water, CO(2), and HPO(3) were seen in VIII. The reaction pathways leading to the production of the observed ions are described. The nominal compounds and the impurities were also separated and identified by capillary electrophoresis with ESI-ITMS detection.

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