Resins complex insoluble chemical compounds that may be administered with the diet to alter the electrolyte balance of the body in the treatment of heart, kidney, and metabolic disorders. For example, in patients on a strict low-sodium diet such resins combine with sodium in the food so that it cannot be absorbed and passes out in the feces.
The transfer of cations between those in a liquid medium and those in a solid polymer. The polymer is termed the cation exchanger. This technique is used in ion-exchange chromatography.