HABA-based ionic liquid matrices for UV-MALDI-MS analysis of heparin and heparan sulfate oligosaccharides.
Polysulfated carbohydrates such as heparin (HP) and heparan sulfate (HS) are not easily amenable to usual ultraviolet matrix-assisted laser desorption/ionization-mass spectrometry (UV-MALDI)-MS analysis due to the thermal lability of their O- and N-SO(3) moieties, and their poor ionization efficiency with common crystalline matrices. Recently, ionic liquid matrices showed considerable advantages over conventional matrices for MALDI-MS of acidic compounds. Two new ionic liquid matrices (ILMs) based on the combination of 2-(4-hydroxyphenylazo)benzoic acid (HABA) with 1,1,3,3-tetramethylguanidine and spermine were evaluated in the study herein. Both ILMs were successfully applied to the analysis of synthetic heparin oligosaccharides of well-characterized structures as well as to heparan sulfate-derived oligosaccharides from enzymatic depolymerization. HABA-based ILMs showed improved signal-to-noise ratio as well as a decrease of fragmentation/desulfation processes and cation exchange. Sulfated oligosaccharides were detected with higher sensitivity than usual crystalline matrices, and their intact fully O- and N-sulfated species [M-Na](-) were easily observed on mass spectra. MALDI-MS characterization of challenging analytes such as heparin octasaccharide carrying 8-O and 4 N-sulfo groups, and heparin octadecasulfated dodecasaccharide was successfully achieved.
Przybylski
Cedric
C
CNRS UMR 8587.
Gonnet
Florence
F
Bonnaffé
David
D
Hersant
Yael
Y
Lortat-Jacob
Hugues
H
Daniel
Regis
R
D001391:Azo Compounds / Q000737:chemistry*; D006493:Heparin / Q000737:chemistry*; D006497:Heparan Sulfate / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000032:analysis* / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet
D001391:Azo Compounds; D006493:Heparin; D006497:Heparan Sulfate; D052578:Ionic Liquids; D009844:Oligosaccharides; C001413:HABA