A triphenylamine as a fluorophore and maleimide as a bonding group selective turn-on fluorescent imaging probe for thiols

•A green turn on fluorescent probe for biothiols in solution was developed.•The detection limit is as low as 10−8 M.•The probe can be applied in bioimaging.

With the biological importance of biothiols, the development of probes for thiols has been an active research area in recent years. Here, we report a novel thiol-reactive fluorescent probe based on Michael addition reaction for selectively detecting thiols over other relevant biological species. The thiol adduct was characterized using NMR and mass spectroscopy and detection mechanism was further confirmed. This sensor with excellent selectivity for biothiols over other amino acids features a rapid signal response time, a good linearity range and a low detection limit. For the practical application of the sensor, it can be used to monitor thiol in live cells with turn-on fluorescence imaging.

Graphical abstractBased on the Michael addition reaction of thiol with the CC bond under mild conditions, we herein report a new fluorescent probe which features a rapid signal response time, a good linearity range and a low detection limit. The potential application of this new fluorescent probe was demonstrated by fluorescent imaging of thiol in living cells.Figure optionsDownload full-size imageDownload as PowerPoint slide