Biochemical Techniques and Instrumentation

2.3.2. Principle

The separation of molecules is achieved by passing the sample over an ion exchange matrix or ion exchanger. The ion exchangers are prepared by covalently linking charged groups or stationery phase to an insoluble support matrix. The support matrix are usually made of cellulose, dextran, agarose or silica. The separation of molecules in the sample is achieved in two stages.

1. The molecule of interest gets adsorbed to the charged matrix while unbound material is removed
2. The bound molecule is later recovered from the matrix by varying the pH or ionic strength of the buffer.