PERIODATE-OXIDATION OF CYCLOSOPHORAOSES - A QUANTITATIVE-ANALYSIS OF THE REACTION-PRODUCTS BY IONSPRAY MASS-SPECTROMETRY

The reaction products from the periodate oxidation of cyclosophoraoses , having glucose residues ranging from 17 to 21, were studied by means of ionspray mass spectrometry. Three different samples exhibiting dif ferent degrees of oxidation (similar to 30, similar to 65 and similar to 85%) were investigated. In order to avoid both insolubility and com plex spectra due to water adduct formation, the oxidised cyclosophorao ses were exhaustively reduced in order to convert the aldehydic functi ons into hydroxyl groups. The individual ions comprising the mass spec tral envelope were assigned by taking into account the coexistence of different degrees of oxidation for each cyclosophoraose member. The di stribution of variable degrees of oxidation was studied in terms of th e statistical Poisson distribution and the experimental data were fitt ed with the expected theoretical distributions. Detection of unfragmen ted ions coupled with both high mit resolution and mathematical modell ing allowed the quantitative definition of the distribution of the deg ree of oxidation for each cyclosophoraose ring size. This information makes possible the use of specific oxidised derivatives as building bl ocks for complex molecular systems. (C) 1998 Elsevier Science Ltd. All rights reserved.