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

Abstract

The activity of atropine on the complexation and transport of Na⁺, K⁺, Mg²⁺ and Ca²⁺ 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⁺, Mg²⁺ and Ca²⁺ ions from an aqueous phase into an organic one with a preference for Ca²⁺ ions. According to a kinetic study, divalent cations (Mg²⁺ and Ca²⁺) 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 proprieties.

Keywords:

• Atropine
• Complexation
• Transport
• Ionophore
• Mono- and divalent cations

Acknowledgements

This work was supported by the Moroccan CNRST and the urban community of Casablanca. The authors would like to thank Dr Nourrddine Chafik (Sothema Laboratories) for helpful corrections of the text.