Solute focusing techniques for bioseparations

The growth of industrial biotechnology has had a major impact on the research and development of both analytical and preparative focusing techniques. Pioneering methods such as isoelectric focusing are being modified to overcome the limitations of batch mode operation, scale up difficulties, high power requirement, and excessive heat generation. present advances in focusing techniques have been made by either overcoming the limitations of standard techniques or by investigating new focusing systems. Here we review the background and history of isoelectric focusing and discuss several new focusing techniques including recycle isoelectric (RIEF), counteracting chromatographic electrophoresis (CACE), and countercurrent gradient chromatography (CGC).