Capillary zone electrophoresis tandem mass spectrometry detects low concentration host cell impurities in monoclonal antibodies

Electrophoresis. 2016 Feb;37(4):616-22. doi: 10.1002/elps.201500301.

Abstract

We have evaluated CZE-ESI-MS/MS for detection of trace amounts of host cell protein impurities in recombinant therapeutics. Compared to previously published procedures, we have optimized the buffer pH used in the formation of a pH junction to increase injection volume. We also prepared a 5-point calibration curve by spiking 12 standard proteins into a solution of a human mAb. A custom CZE-MS/MS system was used to analyze the tryptic digest of this mixture without depletion of the antibody. CZE generated a ∼70-min separation window (∼90-min total analysis duration) and ∼300-peak capacity. We also analyzed the sample using ultra-performance LC-MS/MS. CZE-MS/MS generated approximately five times higher base peak intensity and more peptide identifications for low-level spiked proteins. Both methods detected all proteins spiked at ∼100 ppm level with respect to the antibody.

Keywords: Bottom-up proteomics; CZE; Host cell proteins.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal / analysis*
  • Antibodies, Monoclonal / chemistry*
  • Chromatography, Reverse-Phase / methods
  • Drug Contamination / prevention & control*
  • Electrophoresis, Capillary / methods*
  • Escherichia coli
  • Humans
  • Spectrometry, Mass, Electrospray Ionization / methods
  • Tandem Mass Spectrometry / methods*

Substances

  • Antibodies, Monoclonal