Oligosaccharide profiling: the facile detection of mono-, di- and oligosaccharides by electrospray orthogonal time-of-flight mass spectrometry using 3-aminophenylboronic acid derivatization.
Monosaccharides, disaccharides and larger carbohydrates can be derivatized using 3-aminophenylboronic acid (3-APBA). This procedure is carried out at low pH (2.7-3.0) and allows the use of positive ion mode electrospray orthogonal time-of-flight mass spectrometry (ES-OTOFMS) to analyze the resulting boronate complexes. A carbohydrate profile map of a complex carbohydrate mixture, honey, was prepared which displayed superior sensitivity when compared with lithium ion cationization. Complexes formed using simple mono- and disaccharides show that facile in situ derivatization leads to an equilibrium mixture; which is reproducible for a specific set of electrospray conditions. D-Glucose could be detected at 5 microM concentration using the standard instrument spray interface. Lower detection levels of approximately 500 nM could be achieved using a nanospray device. The 3-APBA complexes are observed on instruments employing a low temperature interface (140-150 degrees C) which allows formation of the boronate species while still promoting efficient desolvation of the ions. The spectral identification of 3-APBA complexed carbohydrates in complex mixtures is facilitated by the easily observed 1 mass unit separated peak pair bearing the 1:4 ratio resulting from the natural isotopic abundance of (10)B and (11)B.
City of Hope National Medical Center and Beckman Research Institute, Dept. of Immunology, 1450 E. Duarte Rd., Duarte, CA 91010, USA.
D
D
Williams
T D
TD
Lee
N
N
Dinh
M K
MK
Young
D001897:Boronic Acids; D006722:Honey / Q000032:analysis; D007785:Lactose / Q000032:analysis / Q000737:chemistry; D008320:Maltose / Q000032:analysis / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D009844:Oligosaccharides / Q000032:analysis* / Q000737:chemistry; D013395:Sucrose / Q000032:analysis / Q000737:chemistry
D001897:Boronic Acids; D009844:Oligosaccharides; C028592:3-aminobenzeneboronic acid; D013395:Sucrose; D008320:Maltose; D007785:Lactose