A coumarin-based fluorescent probe for recognition of Cu2+ and fast detection of histidine in hard-to-transfect cells by a sensing ensemble approach

A coumarin-based fluorescent chemosensor CAQA has been synthesized. It can selectively and sensitively recognize Cu2+ in aqueous acetonitrile solutions. Using the Cu-containing complex CAQA-Cu2+ as a sensing ensemble, the device demonstrates highly selective recognition of His/biothiols and was applied in fluorescence imaging of histidine in hard-to-transfect living cells.