The disaccharide and oligosaccharide analysis using SEC LC/MS and LC/MS/MS was performed as reported previously (19, 20). Briefly, the separation was accomplished by a Superdex Peptide (GE Healthcare) column (3.2 mm × 300 mm), with isocratic solvent (0.016 ml/min, 12.5 mM formic acid, pH titrated to 4.4 by ammonia, in 10% acetonitrile) delivered by a Waters Acquity UPLC. The effluent was coupled with an Applied Biosystem Sciex QSTAR mass spectrometer by TurboIonSpray interface.
