Matrix-assisted ultraviolet laser desorption-ionization time-of-flight mass spectrometry of sulfated mannans from the red seaweed Nothogenia fastigiata

ROSA ERRA-BALSELLS; ADRIANA A, KOLENDER; MARÍA C. MATULEWICZ; HIROSHI NONAMI; ALBERTO S. CEREZO

CARBOHYDRATE RESEARCH

Elsevier Science Ltd.

Lugar: Oxford, Gran Bretaña; Año: 2000 vol. 329 p. 157 - 167

0008-6215

Matrix-assisted ultraviolet laser-desorption ionization time-of-flight mass spectrometry (UV-MALDI-TOF-MS) was applied to sulfated xylo-mannan fractions from Nothogenia fastigiata in order to determine their molecular weights and distribution profiles. The number-average molecular weight calculated from the spectra was similar to that determined by chemical end-group analysis for the lower molecular weight fractions. For the other fractions, the number-average molecular weight was lower than that chemically determined; the increased difference may be attributed to higher desorption difficulties and, consequently, mass-dependent discrimination. A reconstructed spectrum, using the peaks obtained from all the fractions, suggested an unimodal distribution. The best results were obtained by using 2,5-dihydroxybenzoic acid as matrix doped with 1-hydroxyisoquinoline and with harmane and nor-harmane.