New publication of team COSM : “A Squaraine-based Dipicolylamine Derivative Acting as a Turn-on Mercury(II) Fluorescent Probe in Water”
Catarina V. Esteves, Judite Costa, Hélène Bernard, Raphael Tripier and Rita Delgado
A symmetrical squaraine-based ligand, sbdpa, bearing two dipicolylamine (dpa) units, was synthesized for the first time, using an environment friendly procedure, such as one-pot and solvent-free reaction. The sbdpa ligand was found to have a small blue-green emission, in aqueous solution, due to a photoinduced electron transfer (PET) mechanism. Metal complexes of sbdpa with a large panel of cations, Na+, K+, Ag+, Mg2+, Ca2+, Ba2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+, were prepared in aqueous buffered solution and screened, in search of a selective response for one of them. A turn-on fluorescence response was then found only for Hg2+