A bile acid derived potassium ion sensor

Abstract

A chenodeoxycholic acid based K⁺ ion sensor has been designed using a modular approach in which a fluorophore and a cation receptor are attached to the bile acid backbone. In the absence of K⁺ the fluorescence of the molecule is quenched because of through-space, photo-induced electron-transfer from the aza-crown unit. Fluorescence enhancement was observed upon titration with K⁺ (and other alkali metal ions too). In methanol, good selectivity towards the sensing of K⁺ has been observed.