title: Turn-on luminescent sensing of metal cations via quencher displacement: rational design of a highly selective chemosensor for chromium(III).
abstract: A highly selective luminescent chemosensor for Cr(3+) in aqueous solution was assembled by a low-selectivity luminogenic receptor with Cu(2+) as a metal quencher. Three tetranitrogen chelating sites were integrated into the multichannel receptor with a tris(1,10-phenanthroline)ruthenium(II) luminophore at the core. This receptor (2) exhibits chelating affinity for many transition-metal cations, among which Cu(2+) efficiently quenches the emission. The further addition of Cr(3+) into the Cu(2+)-titrated solution of 2 results in a metal-exchange reaction and a sensitive turn-on luminescence response highly selective over other metal cations. The quencher displacement sensing strategy in this design can be a simple but efficient approach for OFF-ON luminescent sensing of metal cations that inherently lack selective ligands.
authors.affiliation: College of Chemistry and Chemical Engineering and Key Laboratory of Analytical Sciences, Xiamen University, Xiamen 361005, China.
authors.forename: Jia-Ni
authors.initials: JN
authors.lastname: Wang
authors.forename: Qiong
authors.initials: Q
authors.lastname: Qi
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Shun-Hua
authors.initials: SH
authors.lastname: Li