Ion exchange chromatography
From Biocrawler, the free encyclopedia.
Ion-Exchange Chromatography
The ion-exchange chromatography process allows the separation of ions and polar molecules based on the electrical properties of the molecules.
Stationary phase: A resin or gel matrix contains covalently bound positive or negative functional groups
Cation exchange column carries negatively charged groups
Anion exchange column carries positively charged groups
(Click here for a list of exchange groups)
Mobile phase: A buffered aqueous solution carries a counter-ion whose charge is
opposite and in equilibrium with the total charge of the resin.
Once the charged analytes are attached to the exchange groups in the column, they must be eluted out using a buffer with a higher ionic strength or a different pH in order to weaken the electrostatic interactions between the analytes and the exchangers.
