RECENT PROGRESS IN THE ELECTROCHROMATOGRAPHY OF PROTEINS

We have constructed a column for the application of an electrical field to a flowing packed bed of chromatographic media (electrochromatography), and we have studied the effect the electrical field on the elution of bovine serum albumin, beta-lactoglobulin A and B, alpha-lactalbumin, and myoglobin from packed beds of Sephadex beads. The elution behavior of the model proteins on Sephadex with a high degree of crosslinking (Sephadex G-25) and with a lower amount of crosslinking (Sephadex G-75) was measured. We confirmed that proteins exhibited an unexplained electrically driven retention on the column packed with G-75. The electrically driven retention effect was greatly reduced or absent in columns packed with the more highly crosslinked G-25. The potential of electrochromatography for high-resolution separations was shown by the partial separation of beta-lactoglobulin A and B by using short columns with the electric field polarity such that electrophoresis opposed convective flow in the column.