The high resolution capacity of polyacrylamide gel electrophoresis (PAGE) (seeChapter 19 ) has resulted in the widespread application of this group of techniques to protein separations. PAGE procedures can provide characterization of proteins in terms of their charge, size, relative hydrophobicity, and abundance. However, they provide no direct clues as to the identity or function of the separated components. A powerful approach to this problem is provided by probing the separated proteins with antibodies and other ligands specific for components of the protein mixture being analyzed.
