MALDI-TOF Mass Spectrometry Analysis of Natural and Synthetic Oligosccharides

ERRA BALSELLS, ROSA; HIROSHI NONAMI,

Fukuoka, Japon

Congreso; Joint Meeting on Environmental Engineering in Agriculture 2004, Fukuoka,; 2004

Japan Society for Environmental Control in Biology

UV-MALDI-TOF-MS is a valuable technique for the determination of high molecular mass when it is used with proteins while for carbohydrates still the technique faces serious experimental problems. This limitation is probably related, at least in part, to the structural complexity and to the molecular interactions often found in the oligosaccharide moieties of these biopolymers. Furthermore, the isolated oligosaccharides include in its structure salts naturally present in cells, which can modify the results of the MS analysis. Few UV-MALDI-MS analysis of polysaccharides belonging to the neutral, anionic and basic families have been reported tacking into account this salt effect although they are naturally present in plant and animal tissues, being their isolation and characterization quite essential. In order to achieve this goal with natural neutral oligosaccharides present in cells, in the present project we designed comparative UV-MALDI-MS experiments conducted on different instruments, with matrices recommended both for carbohydrate (nor-Ho, GA) and protein analysis (SA, CHC), adding extra amount of dopping Na and Ca.  As analytes,  xylans present in the intercellular medium or in the cell walls of algae have been isolated and prepared for UV-MALDI MS analysis. The Na, K, Ca and Mg concentration in the native xylan studied have been determined by atomic absorcion spectroscopy.