Abstract: Native glycopeptides are suitable to FAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the FAB spectra of glycopeptides is the limited number of peaks and the low abundances of fragments. In order to obtain the information of carbohydrate sequence the permethylation of carbohydrate, a well known method, is recommended here. The L-β-aspartamido-carbohydrate from chicken egg albumin was chosen as the model compound of glycopeptides. Our experiments showed obvious carbohydrate-sequence in the spectra of permethylated aspartamido carbohydrates. The key conditions to perform the method are the methylation reagent and purification process for the permethylated derivatives.

Key words: Glycopeptide, Ovalbumin, Permethylation, FABMS