SOLUTE FOCUSING TECHNIQUES FOR BIOSEPARATIONS

The growth of industrial biotechnology has had a major impact on the r esearch and development of both analytical and preparative focusing te chniques. Pioneering methods such as isoelectric focusing are being mo dified to overcome the limitations of batch mode operation, scale up d ifficulties, high power requirement, and excessive heat generation. Pr esent advances in focusing techniques have been made by either overcom ing the limitations of standard techniques or by investigating new foc using systems. Here we review the background and history of isoelectri c focusing and discuss several new focusing techniques including recyc le isoelectric focusing (RIEF), counteracting chromatographic electrop horesis (CACE), and countercurrent gradient chromatography (CGC).