Lanthanide Luminescence Modulation by Cation–π Interaction in a Bioinspired Scaffold: Selective Detection of Copper(I)

Abstract A prototype luminescent turn‐on probe for Cu + (and Ag + ) is described, harnessing a selective binding site (log K ass =9.4 and 7.3 for Cu + and Ag + , respectively) based on the coordinating environment of the bacterial metallo‐chaperone CusF, integrated with a terbium‐ion‐signaling moiety. Cation–π interactions were shown to enhance tryptophan triplet population, which subsequently sensitized, on the microsecond timescale, the long‐lived terbium emission, offering a novel approach in bioinspired chemosensor design.