Sample Pre-Processing for Mass Spectrometric Analysis of Glycoprotein Structure

A novel simple and fast method based on a quadrupole ion trap QIT and a time-of-flight mass spectrograph was developed for the glycosylation site and glycan structure analysis of glycoprotein by in-solution digestion and in-gel digestion which did not need to enrich and label the glycopeptide. Horseradish peroxidase HRP and RNase B were utilised to optimize the conditions of sample pre-processing. The effects of the conditions were investigated separately and the optimal conditions were heat denaturation of RNase B chemical denaturation of HRP RNase B digestion with endoproteinase Lys-C HRP digestion with trypsin 12 - 16 h of digestion 50% acetonitrile-5% trifluoroacetic acid of the extraction solution sandwich spotting method of the sample.