What is the best stain for detecting proteins in polyacrylamide gels?

Improved staining of proteins in polyacrylamide gels including isoelectric focusing gels with clear background at nanogram sensitivity using Coomassie Brilliant Blue G-250 and R-250. Electrophoresis 9, 255–262. Oakley BR et al. (1980). A simplified ultrasensitive silver stain for detecting proteins in polyacrylamide gels. Anal Biochem 105, 361–363.

Can polyacrylamide be used for protein separation?

For protein separation, virtually all methods use polyacrylamide as an anticonvective, sieving matrix covering a protein size range of 5–250 kD. Some less common applications such as immunoelectrophoresis and the separation of large proteins or protein complexes >300 kD rely on the larger pore sizes of agarose gels.

Can acrylamide be used as a gel?

Gels can either use a single concentration of acrylamide where they are optimised for a narrow range of molecular weights (see section 1) or be gradients of acrylamide concentration where they are optimised for a much wider range of weights (see section 2).

Why is acrylamide a size-selective sieve?

When electrophoresis is performed in acrylamide or agarose gels, the gel serves as a size-selective sieve during separation. As proteins move through a gel in response to an electric field, the gel’s pore structure allows smaller proteins to travel more rapidly than larger proteins (Figure 2.1).

What are polyacrylamide gels?

Polyacrylamide gels are a matrix of cross-linked acrylamide monomers with the tightness of the mesh dependent upon the amount of acrylamide and cross-linker present. Different sized proteins therefore require different formulations of acrylamide gel to achieve optimum separation (table 1).

What is sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE)?

Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) is an essential molecular biology technique where complex mixtures of protein are separated in an acrylamide gel according to their molecular weight.