The Synthesis And Applications Of Phenothianine Derivatives-based Fluorescence Probes For Hypochlorous Acid

Reactive oxygen species(ROS)are associated with various physiological and pathological processes,and the concentration of ROS in bodies plays a key role in balancing health.As a type of ROS,hypochlorous acid(HClO),which could partially dissociate to hypochlorite(OCl~-),is associated with innate host defence for killing a wide range of pathogens.However,aberrant accumulation of HClO in phagocytes can trigger tissue damage,lung diseases and rheumatoid arthritis.In our daily life,the ionized form of hypochlorous acid,is particularly important because it is widely used as cleaning agents,disinfectants,and sanitizers in households and industries,but overuse of it may cause serious environmental problems.As a result,development of effective methods for rapid,sensitive and specific detection of HClO in vitro,vivo and environment is urgently in need.In this work,two fluorescence probes,XZ and LB,were developed for monitoring HClO level in biological and environmental samples.XZ and LB were easily synthesized by one-step condensation reaction.Upon addition of HClO,significant changes in the absorption spectra and the colour change of the solution were noticed,facilitating the“naked eye”detection of HClO.The fluorescence of XZ and LB was found to be significantly increased within 1 second and 50 seconds respectively,leading to“OFF-ON”fluorescence response towards HClO.The sensing mechanism,oxidation thioether and C=C in XZ and LB respectively by HClO,was confirmed by HRMS titration analysis.XZ and LB,with a low limit of detection at15.6 nM?2.0?M,feature high sensitivity,selectivity,fast response towards HClO and low toxicity.More importantly,XZ and LB were applied in the recognization of exogenous and endogenous hypochlorite in cells,zebrafish and mice.LB,spercifically,was successfully used in the identification the marker of arthritis and concetration of HClO in different water samples.