A copper(II) rhodamine complex with a tripodal ligand as a highly selective fluorescence imaging agent for nitric oxide

A copper(II) complex CuRBT with a ring-closed rhodamine-containing tripodal ligand was synthesized as a highly selective fluorescent imaging agent for nitric oxide (NO). It featured a 700-fold fluorescent enhancement toward NO from a dark-background with the detection limit of NO about 1 nM in aqueous solution and could be applied for monitoring intracellular NO.