A fluorescent pH chemosensor for strongly acidic conditions based on the intramolecular charge transfer (ICT) effect

A BA-derived fluorescent pH sensor for use under strongly acidic conditions based on the ICT effect was realized to exhibit high stability, sensitivity and selectivity. This probe can be used to detect acidity within the pH range 0.5-2.5. The design strategy may help to develop probes for targets at high concentrations.