Electrofocusing on flat pH gradients: Systematic pH gradient modification leading to improved protein separation

Abstract
A pH gradient providing maximal separation between pH 4.7 and 4.9 was generated by systematic variation of carrier constituent mixtures, and/or selection of anolyte/catholyte. In the optimized pH gradient, separation on gel electrofocusing between proteins with pI's between 4.7 and 4.9 was shown to be superior to that achieved on relatively steep pH gradients. This was the case in the separation of either human growth hormone isohormones D and E, or of bovine serum albumin and ovalbumin.