ion exchange chromatography

chromatography /chro·ma·tog·ra·phy/ (kro″mah-tog´rah-fe) a method of separating and identifying the components of a complex mixture by differential movement through a two-phase system, in which the movement is effected by a flow of a liquid or a gas (mobile phase) which percolates through an adsorbent (stationary phase) or a second liquid phase.chromatograph´ic

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adsorption chromatography  that in which the stationary phase is an adsorbent.

affinity chromatography  that based on a highly specific biological interaction such as that between antigen and antibody or receptor and ligand, one such substance being immobilized and acting as the sorbent.

column chromatography  that in which the various solutes of a solution are allowed to travel down an absorptive column, the individual components being absorbed by the stationary phase.

gas chromatography  (GC) that in which an inert gas moves the vapors of the materials to be separated through a column of inert material.

gas-liquid chromatography  (GLC) gas chromatography in which the sorbent is a nonvolatile liquid coated on a solid support.

gas-solid chromatography  (GSC) gas chromatography in which the sorbent is an inert porous solid.

gel-filtration chromatography , gel-permeation chromatography that in which the stationary phase consists of gel-forming hydrophilic beads containing specifically sized pores that trap and delay molecules small enough to enter them.

high-performance liquid chromatography , high-pressure liquid chromatography (HPLC) a type of automated chromatography in which the mobile phase is a liquid which is forced under high pressure through a column packed with a sorbent.

ion exchange chromatography  that in which the stationary phase is an ion exchange resin.

molecular exclusion chromatography , molecular sieve chromatography gel-filtration c.

paper chromatography  that using a sheet of blotting paper, usually filter paper, for the adsorption column.

partition chromatography  a method using the partition of the solutes between two liquid phases (the original solvent and the film of solvent on the adsorption column).

thin-layer chromatography  (TLC) chromatography through a thin layer of inert material, such as cellulose.

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ion exchange chromatography,

the process of separating and analyzing different substances according to their affinities for chemically stable but very reactive synthetic exchangers, which are composed largely of polystyrene and cellulose. The process uses an absorbent containing ionizing groups and accommodates the exchange of ions between a solution of substances to be analyzed and the absorbent. Ion exchange chromatography is often used to separate components of nucleic acids and proteins elaborated by various structures throughout the body. Different ions deposited in the absorbent during the exchange produce bands of different colors, which constitute a chromatograph. Compare column chromatography, gas chromatography.

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ion (ī´on),

n an atomic particle, atom, or chemical radical bearing an electrical charge, either negative or positive.

ion exchange chromatography,

n the process of separating and analyzing different substances according to their affinities for chemically stable but very reactive synthetic exchangers, which are composed largely of polystyrene and cellulose. The process uses an absorbent containing ionizing groups and accommodates the exchange of ions between a solution of substances to be analyzed and the absorbent. Ion exchange chromatography is often used to separate components of nucleic acids and proteins.

ion pair,

n the two particles of opposite charge, usually the electron and the positive atomic residue resulting after the interaction of ionizing radiation with the orbital electrons of atoms. The average energy required to produce an ion pair is approximately 33 (or 34) electron volts.

ion-selective electrode,

n a potentiometric electrode that develops a potential in the presence of one ion (or class of ions), but not in the presence of a similar concentration of other ions.