Ionophoric properties of atropine: complexation and transport of Na+, K+, Mg2+ and Ca2+ ions across a liquid membrane.

The activity of atropine on the complexation and transport of Na(+), K(+), Mg(2+) and Ca(2+) ions across a liquid membrane was investigated using a spectrophotometric method. Atropine is a natural drug that blocks muscarinic receptors. It is a competitive antagonist of the action of acetylcholine and other muscarinic agonists. Atropine is shown to extract Na(+), K(+), Mg(2+) and Ca(2+) ions from an aqueous phase into an organic one with a preference for Ca(2+) ions. According to a kinetic study, divalent cations (Mg(2+) and Ca(2+)) are more rapidly transported than monovalent ones (Na(+) and K(+)). In both complexation and transport, the flux of the ions increases with the increase of atropine concentration. Atropine might act on the membrane permeability; its complexation and ionophoric properties shed new lights on its therapeutic properties.