Abstract: In this report, we present a novel analytical focusing electrophoresis technique. The principle of the technique is based on the mobility differences and has been proved successfully in our laboratory. The technique is of the same applicability as that of CZE, not limited to the protein like big molecules, with greatly improved efficiency of separation and enrichment. Advantages of this novel technique are:1. Since large volume of dilute sample solution can be injected and very narrow and concentrated zones can be obtained, extremely dilute sample can be analyzed by this novel technique in comparison with CZE. 2. Instead of with extremely small injection volume (nanoliters or less) in CZE, microliter quantities of sample can be injected in this novel technique. This quantity is similar to that in HPLC and is much easier to be handled. 3. Since species in a mixture are separated on the basis of their mobility differences, the field of application is as wide as that of CZE and is much wider than that of IEF (not restricted in proteins and no pH gradient is needed). 4. The separated narrow zones of different samples are stationary after focusing at different positions along the electrophoresis channel. Therefore, the length of the electrophoresis channel can be shortened to several centimeters and the applied voltage can thus be reduced to several hundreds of volts. This will facilitate the fabrication of miniaturized instrument and the optical detection system for an array of electrophoresis channels.

Key words: Electrophoresis, Focusing