Judiciously designed cyanine based fluorogenic probe (L) can exhibit interesting solvent polarity induced isomerization. The probe displayed a highly selective TURN-ON fluorescence response towards hypochlorite among various reactive oxygen species (ROS) and analytes in a mixed aqueous medium. Thesensing process was attributed to the formation of a probe-OCl adduct which results in restricting the donor acceptor extended conjugation. The detection limit was found to be as low as 3 μM. The proposed sensing mechanism is supported by mass spectrometric analysis and HPLC study
