Rapid quantitative capillary zone electrophoresis method for monitoring the micro-heterogeneity of an intact recombinant glycoprotein.
A simple high-resolution capillary zone electrophoresis (CZE) method capable of rapidly assessing the micro-heterogeneity of a 24 kDa molecular weight glycoprotein, has been developed. Separation is carried out using a bare silica capillary at a pH of 2.5 in a commercially available electrophoresis buffer system composed of triethanolamine and phosphoric acid. Over 30 peaks were detected within a run time of 15 min using a 27 cm capillary and approximately 60 peaks were detected using a 77 cm capillary. Although most of the peaks arise from differences in the oligosaccharide structures present on the one glycosylation site on this molecule, other forms of micro-heterogeneity due to the presence of the nonglycosylated form of this glycoprotein and various types of chemical degradation, e.g., deamidation, are also responsible for the multitude of peaks observed. Although the exact chemical identity of each peak in the resulting electropherogram of this glycoprotein is not known, useful information can be obtained for assessing comparability, stability, and batch consistency. Factors impacting the resolution, precision, accuracy, and robustness of the assay are also discussed along with inherent advantages and limitations associated with measuring the micro-heterogeneity of intact glycoproteins.
Berkowitz
Steven A
SA
Department of Analytical Development, Biogen Idec Inc., 14 Cambridge Center, Cambridge, MA 02142, USA. steven.berkowitz@biogenidec.com
Zhong
Huijuan
H
Berardino
Martha
M
Sosic
Zoran
Z
Siemiatkoski
Joseph
J
Krull
Ira S
IS
Mhatre
Rohin
R
D017920:Antiporters; D002021:Buffers; D019075:Electrophoresis, Capillary / Q000379:methods*; D004983:Ethanolamines / Q000737:chemistry; D006023:Glycoproteins / Q000032:analysis* / Q000302:isolation & purification / Q000378:metabolism; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D008991:Monitoring, Physiologic; D009439:Neuraminidase / Q000378:metabolism; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase / Q000378:metabolism; D010756:Phosphoric Acids / Q000737:chemistry; D011994:Recombinant Proteins / Q000032:analysis; D015203:Reproducibility of Results; D013997:Time Factors
D017920:Antiporters; D002021:Buffers; D004983:Ethanolamines; D006023:Glycoproteins; D010756:Phosphoric Acids; D011994:Recombinant Proteins; C009546:triethanolamine; C030242:phosphoric acid; D009439:Neuraminidase; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase