High-performance membrane chromatography

In gradient chromatography for proteins migrating along the chromatographic column, the critical distance X0 has been shown to exist at which the separation of zones is at a maximum and band spreading is at a minimum. With steep gradients and small elution velocity, the column length may be reduced to the level of membrane thickness--about one millimeter. The peculiarities of this novel separation method for proteins, high-performance membrane chromatography (HPMC), are discussed and stepwise elution is shown to be especially effective. HPMC combines the advantages of membrane technology and high-performance liquid chromatography, and avoids their drawbacks.