BODIPY based fluorescent turn-on sensor for highly selective detection of HNO and the application in living cells

On the basis of BODIPY platform, a terpyridyl-substituent BODIPY-Copper complex (Cu(II)-BTPY) was rationally designed and synthesized as a redox reaction fluorescent sensor for detecting HNO over reactive oxygen species (ROS) and reactive nitrogen species (RNS) with impressive selectivity in living cells under mild and neutral conditions. The BTPY exhibits relatively high fluorescence quantum efficiency as much as 34.8% and presents large stokes shift, about 62 nm. When a series of transition metal ions were exploited to investigate the fluorescence quench towards BTPY, copper ion (Cu2+) gave the optimal result. After the fluorescence of the probe being effectively quenched in the presence of Cu2+, it can be in turn recovered through the reduction of Cu2+ into Cu+ by HNO accompanying with a visually observable fluorescence response. Still, the sensing mechanism was evidently confirmed by EPR and ESI-MS measurement. In addition, the employment of BTPY for imaging dyes was also presented in vivo. (C) 2019 Published by Elsevier Ltd.