Magnesium-selective ion-channel mimetic sensor with a traditional calcium ionophore.

A novel magnesium-selective ion-channel mimetic sensor based on a well-known calcium ionophore, ETH 5234, was demonstrated. Due to different stoichiometry of the ionophore with Mg(2+) and Ca(2+), the sensor exhibits high selectivity to Mg(2+) by controlling ionophore concentration on the electrode surface, which allows the measurement of Mg(2+) in a 1 mM Ca(2+) background solution.