Peptide mapping by thin-layer chromatography and high voltage electrophoresis

Thin-layer chromatography and electrophoresis, either separately or in combination, provide a simple, high resolution technique for producing peptide maps. Recently, thin-layer methods have tended to be increasingly overshadowed by the development of high performance liquid chromatography (HPLC). Although thin-layer methods are generally not as sensitive as HPLC (requiring milli- or microgram amounts of protein instead of the nanogram or less quantities used in HPLC), they are still preferred for many applications. Thin-layer peptide mapping not only has the advantage of being relatively inexpensive, but it is also a very simple technique and it is often possible to analyze a large number of different samples in a single experiment. In addition, a number of different stains can be used for the detection of specific amino acids and these considerably increase the value of this method.