Exclusion chromatography gel filtration

Gel permeation chromatography, exclusion chromatography. gel filtration chromatography. A technique for separating the components of a mixture according to molecular volume differences. A porous solid phase (a polymer, molecular sieve) is used which can physically entrap small molecules in the pores whilst large molecules pass down the column more rapidly. A solvent pressure up to 1000 psi may be used. 

If the sample components are sufficiently different in size, then it is worth trying size-exclusion chromatography (gel filtration in the case of polar samples, gel permeation for apolar samples). Molecules with a molar mass in excess of 2000 are... 

Size exclusion was first noted in the late fifties when separations of proteins on columns packed with swollen maize starch were observed (Lindqvist and Storgards, 1955 Lathe and Ruthven, 1956). The run time was typically 48 hr. With the advent of a commercial material for size separation of molecules, a gel of cross-linked dextran, researchers were given a purposely made material for size exclusion, or gel filtration, of solutes as described in the classical work by Porath and Flodin (1959). The material, named Sephadex, was made available commercially by Pharmacia in 1959. This promoted a rapid development of the technique and it was soon applied to the separation of proteins and aqueous polymers. The work by Porath and Flodin promoted Moore (1964) to apply the technique to size separation, gel permeation chromatography of organic molecules on gels of lightly cross-linked polystyrene (i.e., Styragel). 

In molecular exclusion chromatography (also called size exclusion or gel filtration or gel... 

Molecular exclusion chromatography, also known as gel filtration, size exclusion chromatography, gel permeation chromatography, or simply gel chromatography, is another separation method based on differences in molecular size. 

Size-exclusion chromatography (gel permeation chromatography gel filtration) is based on the ability of molecules to penetrate chromatography particles... 

W.W. Yau, D.D. By and J.J. Kirkland, Modern Size Exclusion Liquid Chromatography Practice of Gel Permeation and Gel Filtration Chromatography, J. Wiley and Sons, New York, 1979. ISBN 0471033871. 

The evolution of media covering aqueous and nonaqueous systems on the one hand and analytical as well as microscale and macroscale preparative applications on the other hand has resulted in an arbitrarily nomenclature within the field. Thus the current practice is to refer to the separation principle based on solute size as size exclusion chromatography (SEC) whereas the application in aqueous systems is traditionally referred to as gel filtration (GF) and the application in nonaqueous systems is designated gel-permeation... 

Size exclusion HPLC has many other common names, such as gel permeation, gel filtration, steric exclusion, molecular sieve chromatography, or gel chromatography. These names all reflect the theoretical mode of action for this type... 

Figure 4-2. Size-exclusion chromatography. A A mixture of large molecules (diamonds) and small molecules (circles) are applied to the top of a gel filtration column. B Upon entering the column, the small molecules enter pores in the stationary phase matrix from which the large molecules are excluded. C As the mobile phase flows down the column, the large, excluded molecules flow with it while the small molecules, which are temporarily sheltered from the flow when inside the pores, lag farther and farther behind.

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