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

A prototype luminescent turn-on probe for Cu+ (and Ag+) is described, harnessing a selective binding site (log Kass=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.