The highly poisonous mercury’s bioaccumulation and contamination imposes a great threat to the living organisms and could jeopardize the ecosystem in global dimension. Organo mercury species (like, CH3HgX, X = halides, etc)are known to be more toxic and virulent as it readily crosses the blood-brain barrier, resulting the damage of the central nervous system in addition to other organs.1 Our continuing efforts to develop versatile molecular probes with several useful features such as environmental monitoring, and easy-to-use quantification of mercury species have led us to investigate a ratiometric version of the reactive probe for mercury species as it is less sensitive to the errors associated with the probe concentration, photobleaching, instrument’s sensitivity and environmental effects.2
Herein, we have developed a ratiometric fluorescent probe for mercury species based on the metal-promoted hydrolysis of a vinyl ether derivative of 2-(benzothiazol-2-yl)phenol in a buffer solution. Vinyl ether N-(3-(benzo[d]thiazol-2-yl)-4-(vinyloxy)phenyl)acetamide was found as an optimal probe for mercury species as it shows better reactivity, solubility, and photophysical properties compared with the others derivative of 2-(benzothiazol-2-yl)phenol. The probe responses selectively to mercury species over various other metal ions with a marked fluorescence change from blue to cyan through the excited state intramolecular proton transfer (ESIPT) process.
1. (a) ATSDR 2005. ToxProfiles: Mercury: Atlanta, G. A, U.S. Department of Health and Human Services; (b) P. Jitaru, F. Adams, J. Phys. IV France, 121(2004) 185; (c) T.W. Clarkson, L. Magos, Off. Rev. Toxicology, 2006, 36, 609.
2. (a) Grynkiewicz, G.; Poenie, M.; Tsien, R. Y. J. Biol. Chem. 1985, 260, 3440. (b) Banthia, S.; Samanta, A. J. Phys. Chem. B. 2006, 110, 6437.