Principles and Practice of Chromatography - The Control of Chromatographically Available Stationary Phase (V<sub>s</sub>) > Stationary Phase Limitation by Exclusion > Page 42

Courtesy of Supelco Inc.

 

Figure 19 The Separation of a Mixture by Exclusion Chromatography

 

Until relatively recently, silica has been the most commonly used exclusion media for the separation of high molecular weight hydrocarbons and polymers. However, it was not so successful in the separation of polymeric materials of biological origin. More recently the micro-reticular macroporous polystyrene gels have been introduced and found to be very useful for the separation of biopolymers by size exclusion. These materials have even replaced many of the traditional applications of silica gel.

In summary, in all types of chromatography, solute retention is controlled by either the magnitude and probability of interaction and/or by the amount of stationary phase that is available to them. However, even if, by appropriate choice of the phase system, the solutes are separated, unless the peak dispersion is contained to allow the individual solutes to be eluted discretely, the mixture will not be resolved.