Renovated multifunctional colorimetric/fluorometric sensor for simultaneous detection, imaging of pH variance and antimicrobial therapies

Abstract pH is an essential aspect of the intracellular environment and potentially affect virtually all cellular processes. Tracking pH changes in diverse heterogeneous environments thus become so important. Most of studies have reported the development of molecular pH sensors based on different response mechanisms. However, multifunctional pH probes which can integrate pH sensing and other job duties such as illness treatment are rarely reported. In this study, we have created such a sensor NNBDH which is based on conjugation of the norfloxacin and NBD (as the fluorophore) molecules and the subsequent studies indicated that NNBDH can sensitively and selectively sense pH changes in water, live cells and zebrafish via a colorimetric and fluorometric response with good reversibility, stability and cell or animal tissue permeability and compatibility. Even more interesting is that NNBDH can offer concurrent potent antibacterial therapies against the superbug MRSA. This 2-in-1 pH sensor can be very useful in coping with some clinical situations often manifested by rising pH and subsequent bacterial infections such as S. aureus or even fatal MRSA. The current proof-of-study is paying way for developing a new generation of economic, fast-response and multifunctional molecular pH sensors which can do not only sensing but also treating and healing.