Free-flow electrophoresis. III. An analytical version for a rapid, quantitative determination of electrophoretic parameters.

An analytical device based on the principle of free-flow electrophoresis is described. Electrophoretic mobility distributions of proteins or cells can be obtained quickly with field-strengths of about 140 V/cm. Up to 100 samples can be tested per hour. The accuracy and reproducibility of the device is illustrated by the example of the serum protein separation. Quantities in the picomole range can be quantitatively evaluated. In the course of mobility measurements of cells and cell mixtures, a reproducibility of +/- 1.4% was obtained. Therefore this device meets both the needs of electrokinetic research and the requirement of routine measurements in clinical diagnosis. Finally, the application of a pH gradient is described and the limitation due to methodical aspects is shown.