An organic compound that will adsorb ions under some conditions and release them under others.
Synthetic organic substances of high molecular weight. They replace certain negative or positive ions that they encounter in solutions.
An ionizable synthetic substance, which may be acid or basic, used accordingly to remove either acid or basic ions from solutions. Anion exchange resins are used to absorb acid in the stomach, and cation-exchange resins are used to remove basic (alkaline) ions from solutions.