New Photochrome Probe Allows Simultaneous pH and Microviscosity Sensing
Steele, Terry W. J.
Marks, Robert S.
School of Materials Science and Engineering
4-N,N′-dimethylamino-4′-N′-stilbenemaleamic acid (DASMA), a unique molecular photochrome probe that exhibits solubility and retains trans-cis photoisomerisation in a wide range of organic solvents and aqueous pH environments, was prepared, purified and chemically characterised. Absorption, fluorescence excitation and emission spectra and constant-illumination fluorescence decay were measured in acetonitrile, dimethyl sulfoxide, ethanol, propylene carbonate, and aqueous glycerol mixtures. The pseudo-first-order fluorescence decay rates were found to be strongly dependent on the medium viscosity. In addition, the molecule exhibited the pH-dependent fluorescence and photoisomerisation kinetics.
Journal of Fluorescence
© 2015 Springer Science+Business Media. This is the author created version of a work that has been peer reviewed and accepted for publication by Journal of Fluorescence, Springer Science+Business Media. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1007/s10895-015-1577-2].