Title: Enumeration of Carbohydrate Hydroxyl Groups by Silylation and Matrix Assisted Laser Desorption/ionization Time-of-Flight Mass Spectrometry Authors
Submitted to: Rapid Communications in Mass Spectrometry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 2, 2007
Publication Date: June 11, 2007
Citation: Adeuya, A., Price, N.P. 2007. Enumeration of carbohydrate hydroxyl groups by silylation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Rapid Communications in Mass Spectrometry. 21:2095-2100. Interpretive Summary: Besides their importance to the food industry, carbohydrates from agricultural sources are becoming increasingly important as precursors for fuel ethanol. Predicting how carbohydrates are degraded requires detailed knowledge of their chemical composition. Chemically analysis of sugars relies on mass spectrometry (MS) because it is rapid and often gives characteristic exact molecular weights. This report describes a new MS technique to evaluate the number of hydroxyl groups on carbohydrates. The method is based on the increase in mass observed when the carbohydrates are treated with a silylating agent. The method has been used for several carbohydrates of potential agricultural importance. It will be primarily of value to scientists and engineers in the sugar industry.
Technical Abstract: A method for enumerating hydroxyl group in analytes is described and applied to various carbohydrates and polyols. The analytes were derivatized in solution by using trimethylsilylimidazole (TMSI) and the products were analyzed without chromatography in a MALDI-TOF-MS. The mass spectra revealed consecutive product ion peaks that are separated by 72 mass units. This 72 mass unit separation is a result of displacement of a hydroxyl hydrogen atom by a TMS group. The number of the observed peaks was used to confirm the number of hydroxyl group in each analyte. This method was utilized in analysis of single and multi-component analytes. This is the first report of functional group quantitative analysis by using MALDI-TOF-MS.