A Novel Luminescent pH Sensor Based on a Tricarbonylpolypydridylrhenium(I) Complex with Trhree Protonation Sites

CATTANEO, MAURICIO; FAGALDE, FLORENCIA; KATZ, NÉSTOR E.; BORSARELLI, CLAUDIO

Jerusalem, Israel

Congreso; XXXVIII International Conference on Coordination Chemistry; 2008

IUPAC

Following a previous report on proton-induced luminescence changes of tricarbonylpolypyridylrhenium(I) complexes,[1] we address in this work the possibility of increasing the dynamic range of pH-sensing by using a complex with three protonation sites: the ion [Re(4,4?-(CO2H)2-bpy)(CO)3(4,4?-bpy)]+, (bpy = 2,2?-bipyridine, 4,4?-bpy = 4,4?-bipyridine), synthesized as a CF3SO3- salt, and characterized by spectroscopic, electrochemical and photophysical techniques. By studying the pH dependence in aqueous solution of its luminescence decay, three values of pKa* could be determined, as shown in the Figure. The amplification factor is near 13, making it a promising luminescent pH sensor of the on-off-on type over a pH range of 0-8. [1] M. Cattaneo, F. Fagalde, N. E. Katz, C. D. Borsarelli, T. Parella, Eur. J. Inorg. Chem. 2007, 34, 5323-5332. [1] M. Cattaneo, F. Fagalde, N. E. Katz, C. D. Borsarelli, T. Parella, Eur. J. Inorg. Chem. 2007, 34, 5323-5332. [1] M. Cattaneo, F. Fagalde, N. E. Katz, C. D. Borsarelli, T. Parella, Eur. J. Inorg. Chem. 2007, 34, 5323-5332. [1] M. Cattaneo, F. Fagalde, N. E. Katz, C. D. Borsarelli, T. Parella, Eur. J. Inorg. Chem. 2007, 34, 5323-5332.