an·i·on ex·change
(an'ī-on eks-chānj'), The process by which an anion in a mobile (liquid) phase exchanges with another anion previously bound to a solid, nonmobile, positively charged phase, the latter being an anion exchanger. For example, the process takes place when Cl- is exchanged for OH- in desalting. The reaction is Cl- (in solution) + (OH- on anion exchanger+) → (Cl- on anion exchanger) + OH- (in solution); in combination with the cation exchange, NaCl is removed from solution. Anion exchange may also be used chromatographically, to separate anions, and, medicinally, to remove an anion (for example, Cl-) from gastric contents or bile acids in the intestine.
Farlex Partner Medical Dictionary © Farlex 2012
ion-ex·change chro·ma·tog·ra·phy
(ī'on-eks-chānj' krō'mă-tog'ră-fē) Chemical investigation in which cations or anions in the mobile phase are separated by electrostatic interactions with the stationary phase.
See also:
anion exchange,
cation exchange
cat·i·on ex·change
(kat'ī-on eks-chānj') The process by which a cation in a liquid phase exchanges with another cation present as the counter-ion of a negatively charged solid polymer (cation exchanger). Cation exchange may be used chromatographically, to separate cations, and medicinally, to remove a cation.
See also:
anion exchange
an·i·on ex·change
(an'ī-on eks-chānj') The process by which an anion in a mobile (liquid) phase exchanges with another anion previously bound to a solid, positively charged phase, the latter being an anion exchanger. Anion exchange may also be used chromatographically, to separate anions, and medicinally, to remove an anion (e.g., Cl-) from gastric contents or bile acids in the intestine.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
ion exchange
A reversible chemical reaction in which ions in a solution are replaced by others with like charge from an insoluble solid such as an ION EXCHANGE RESIN. The process is used for softening hard water, purifying sugar, separating radioactive isotopes and for other purposes.Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005