A turn on fluorescent sensor for cyanide based on ICT off in aqueous and its application for bioimaging

A turn on fluorescent probe for cyanide has been rationally constructed based on an intramolecular charge transfer (ICT) mechanism. Upon treatment with cyanide, probe 1 exhibited a strong fluorescence emission based on blocking ICT. The emission showed good linearity with the cyanide concentration in the range of 0-1.8 mu M, and the detection limit measured to be as low as 0.05 mu M. The NMR experiments confirmed that the ratiometric response of probe 1 to cyanide is due to the electrophilic addition reaction, which results in the inhibition of the ICT process in the probe. Furthermore, the qualitative determination of exogenous cyanide in HepG2 cells demonstrated that the probe can be employed to detect exogenous cyanide in real biological samples. (C) 2015 Elsevier B.V. All rights reserved.