SIMPLE APPROACH TO ELIMINATING DISTURBANCES IN ISOELECTRIC-FOCUSING CAUSED BY THE PRESENCE OF SALTS

It is well known that the resolution in isoelectric focusing (IEF) is impaired by the presence of salts, partly due to a decrease in the width of the pH gradient. In addition, the risk of precipitation increases and the mobilization time for focused protein zones, an important step in IEF in capillary electrophoresis, is prolonged. To eliminate these drawbacks, an on-tube desalting technique for IEF was developed, based on an automatic substitution of the salts with an ampholyte solution in a short focusing step prior to the final analytical isoelectric focusing procedure.