Send to

Choose Destination
See comment in PubMed Commons below
J Chromatogr A. 1998 Jul 24;814(1-2):43-54.

Quasi-linear pH gradients for chromatofocusing using simple buffer mixtures: local equilibrium theory and experimental verification.

Author information

  • 1Department of Chemical and Biochemical Engineering, University of Maryland Baltimore County 21250, USA.


Chromatofocusing utilizes internally generate, retained pH gradients to focus proteins into narrow chromatographic bands. One of the characteristics of current chromatofocusing methods is that they use expensive polyampholyte buffers containing large numbers of ill-defined components in order to generate linear or quasi-linear pH gradients. In addition to being costly to use, polyampholyte buffers also tend to associate with proteins and often yield irreproducible gradient shapes. In order to avoid the various difficulties associated with the use of polyampholyte buffers, this study investigates the use of mixtures of simple buffering species to generate quasi-linear pH gradients on a weak-base ion-exchange column packing. The ability of these gradients to separate protein mixtures was also investigated. To optimize the conditions used, a computer simulation method using a local equilibrium model developed that predicts the shape of the pH gradient. Several experiments were performed that demonstrate the usefulness of the method and the accuracy of the model.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Loading ...
    Write to the Help Desk