Quantitative MALDI-TOF-MS Using Stable-isotope Labeling: Application to the Analysis of N-glycans of Recombinant α-1 Antitrypsin Produced Using Different Culture Parameters.

It is usually difficult to compare quantitatively different sets of glycan samples that have slight differences among themselves using MALDI-TOF-MS. To overcome this problem, 13C-labeled glycans were used as internal standards during the measurement of the N-glycan samples permethylated with 12C-methyl iodide. This method was used to analyze the N-glycans from human α-1 antitrypsin (A1AT) that was recombinantly produced using various culture parameters. Several pH values, dissolved oxygen concentrations, and temperatures were used to produce A1AT using a batch process system, and we investigated the extent to which the glycosylation pattern of A1AT was influenced by these parameters. [ABSTRACT FROM AUTHOR]