title: Concentration of fluoride in plaque - a possible mechanism.
abstract: A mechanism of concentration of fluoride (and phosphate) ions in plaque is suggested: calcium ions from saliva are bound to fixed acidic groups in the plaque, and fluoride (or phosphate) ions are attracted to the bound calcium as counterions. The principle was demonstrated by equilibrium dialysis of calcium-treated acidic ionic exchange material (Sephadex SP and CM) against 1 part/10(6) of fluoride. A part of the fluoride was found to be bound under these conditions.
mesh_terms: D001665:Binding Sites; D001692:Biological Transport; D002118:Calcium / Q000032:analysis; D003773:Dental Plaque / Q000032:analysis; D005459:Fluorides / Q000032:analysis; D009994:Osmolar Concentration; D010710:Phosphates / Q000032:analysis
chemical_list: D010710:Phosphates; D005459:Fluorides; D002118:Calcium