SDS-PAGE is the abbreviated form of sodium-dodecyl sulphatepolyacrylamide gel electrophoresis. It is a commonly used gel electrophoresis for the
qualitative estimation of proteins. It is based on the principle that treatment of protein
with SDS, an anionic detergent, causes a constant negative charge throughout the
protein surface. It also breaks the protein chain into smaller peptide chains. Hence, the
separation of proteins is solely based on the size and shape of the fragments generated
and is independent of the charge of the protein. This, combined with polyacrylamide
gel electrophoresis, allows for visualization of these fragments where the smaller
fragments retain at the bottom of the gel. This method has been discussed in detail in
this chapter.
Keywords: Electrophoresis, SDS-PAGE, Size based separation, Protein.
