1,8-Naphthalimide-Cu(ІІ) ensemble based turn-on fluorescent probe for the detection of thiols in organic aqueous media

A naphthalimide-Cu(II) ensemble was rationally designed and synthesized as a new turn-on fluorescent probe utilizing the 'chemosensing ensemble' method for detections of thiols (Cys, Hcy and GSH) with high selectivity over other α-amino acids. The recognition mechanism was attributed to the remove of Cu(II) from the naphthalimide-Cu(II) ensemble by thiols and the release of florescence of ligand 1. Remarkable fluorescence enhancements were therefore observed in the sensing process of thiols by the naphthalimide-Cu(II) ensemble in the vitro assays and in the fluorescence imaging in CHO cells with high sensitivity and selectivity.