A facile method for cellular N-glycomic profiling by matrix-assisted laser desorption/ionization mass spectrometry

Conventional protocols for cellular N-glycan profiling often need several time-consuming and labor-intensive steps, and a large amount of material (5–20 × 106 cells) is required. In this study, an optimized co-derivatization method was applied for convenient, rapid and highly-sensitive analysis of cellular N-glycan. Taking human cervical carcinoma cells (HeLa) as a model, the required amount for comprehensive cellular N-glycans analysis was reduced down to an original cell number of 105 and the total analysis time was decreased from several days to several hours. Good reproducibility of the method was also obtained with the CV averaging to less than 13.1%. In addition, compared to permethylation derivatization, more than 5-fold sensitivity improvement was achieved and more concise and clear mass spectra were obtained with the new developed method. As a preliminary study, this method was also successfully applied to reveal the difference in cellular N-glycan profiling of two heterogeneous live cell lines, human normal liver cells (L-02) and human hepatocyte carcinoma cells (HepG2), showing great potential for high-throughput analysis of N-glycans from limited cell samples, such as primary cell lines, cells obtained from cell sorting and small size cancer specimens.