Serum protein analysis on immobilized pH gradients with in situ adsorption of albumin on Dextran Blue

Dextran Blue incorporated in concentrations up to 1% w/v into a gel layer buffered with Immobiline chemicals to pH 9.1 does not interfere with isoelectric focusing within an adjacent immobilized pH gradient (IPG) and retains its ability to strongly bind human serum albumin. With minor modifications of the procedure, it is possible to use Dextran Blue shelves in connection with either non‐denaturing or denaturing (i. e. containing 8 M urea) analysis media. Examples include easier typing of group‐specific component in an ultranarrow IPG against a completely clear background and improved resolution of transferrin and hemopexin in two‐dimensional separations.