The AAPS Journal

, Volume 15, Issue 4, pp 962–969

Silica Colloidal Crystals as Emerging Materials for High-Throughput Protein Electrophoresis

  • Nadine K. Njoya
  • Robert E. Birdsall
  • Mary J. Wirth
Research Article Theme: Aggregation and Interactions of Therapeutic Proteins

DOI: 10.1208/s12248-013-9506-2

Cite this article as:
Njoya, N.K., Birdsall, R.E. & Wirth, M.J. AAPS J (2013) 15: 962. doi:10.1208/s12248-013-9506-2

Abstract

Silica colloidal crystals are a new type of media for protein electrophoresis, and they are assessed for their promise in rapidly measuring aggregation of monoclonal antibodies. The nature of silica colloidal crystals is described in the context of the need for a high-throughput separation tool for optimizing the formulations of protein drugs for minimal aggregation. The fundamental relations between molecular weight and mobility in electrophoresis are used to make a theoretical comparison of selectivity between gels and colloidal crystals. The results show that the selectivity is similar for these media, but slightly higher, 10%, for gels, and the velocity is inherently lower than that for gels due to the smaller free volume fraction. These factors are more than compensated for by lower broadening in colloidal crystals. These new media give plate heights of only 0.15 μm for the antibody monomer and 0.42 μm for the antibody dimer. The monoclonal antibody is separated from its dimer in 72 s over a distance of only 6.5 mm. This is five times faster than size-exclusion chromatography, with more than tenfold miniaturization, and amenable to parallel separations, all of which are promising for the design of high-throughput devices for optimizing protein drug formulations.

Key words

colloidal crystalelectrophoresishigh throughputminiaturizationmonoclonal antibodyplate height

Copyright information

© American Association of Pharmaceutical Scientists 2013

Authors and Affiliations

  • Nadine K. Njoya
    • 1
  • Robert E. Birdsall
    • 1
  • Mary J. Wirth
    • 1
  1. 1.Department of ChemistryPurdue UniversityWest LafayetteUSA