Over the last decade, monoliths or continuous beds have emerged as an alternative to traditional packed-bed columns for use in capillary electrochromatography (CEC) and micro-high performance liquid chromatography (micro-HPLC). Monolithic columns can be divided into two categories: silica-based monolithic columns and rigid organic polymer-based monolithic columns resulting from the polymerization of acrylamide, styrene, acrylate or methacrylate monomers. In this paper, the chemistry and most recent applications of these various types of monoliths in both CEC and micro-HPLC are presented.

A simple SPE LC-MS analysis was developed for direct, simultaneous quantification of insulin glargine, detemir, aspart and glulisine.

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The synthesis of three analogues of pyrochlorophyll a with the selective removal of the carbonyl functions is described; 7-despropionate-7 -propyl -mesopyrochlorophyllide a ( D PC), methyl 9-desoxomesopyroc hlorophyllide a ( DOC) and 9-desoxo-7 -despropionate-7propyl-mesopyrochlorophyll ide a (DODPC), were prepared from methyl mesopyropheophorbide a by the extension of known preparative methods. A detailed study of the aggregation of these compounds in solution, using the NMR shifts observed upon dissociation of the aggregates formed in CDCI, solution by the addition of [2H,]methanol, together with the application of the ring current theory of the porphyrin ring is given. In DPC the observed aggregation shifts can be given a precise explanation in terms of a sandwich type dimer with an interplanar separation of ca. 4.2-4.7 A. All the dimer models considered allow for coordination between the C-9 keto group and the magnesium atom of the adjoining molecule, probably via a bridging water molecule. In DOC the calculated dimer shifts based on the sandwich type dimers also give a reasonable explanation of the observed shifts, although now it is the C-7c carbonyl group which is positioned so as to complex with the magnesium atom of the adjacent porphyrin molecule, with a smaller interplane separation of ca. 3.7-3.9A. which may imply direct coordination of the carbonyl and the magnesium atom. In DODPC, in which no carbonyl function is present, there is no evidence of any aggregation in solution. Thus in this metallochlorin there is no 7t-7t attractive interaction, in complete contrast to the analogous metalloporphyrins.

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