Cd(ii)-terpyridine-based complex as a ratiometric fluorescent probe for pyrophosphate detection in solution and as an imaging agent in living cells

Abstract

The terpyridine anthracene ligand L1 was synthesized and characterized. L1 is a ratiometric fluorescent probe for Cd²⁺ with a recognition mechanism based on intramolecular charge transfer (ICT). An L1-Cd(II) complex was isolated, and its structure was established using single-crystal XRD. The L1-Cd(II) complex was able to serve as a novel reversible chemosensing ensemble to allow ratiometric response to pyrophosphate (PPi) in aqueous media. Moreover, the fluorescence imaging in living cells from these two emission channels suggested that L1 was a ratiometric probe for Cd²⁺, and the in situ generated L1-Cd(II) complex was also a ratiometric ensemble for PPi detection in living cells.