Abstract
Steady-state absorption and emission as well as time-resolved emission spectroscopies were employed to study the photophysics and photochemistry of d-luciferin, the firefly active bioluminescent compound. In aqueous solution the electronically excited-state protonated d-luciferin compound undergoes an efficient process of proton transfer to the solvent, with a rate constant k PT = 3.0 × 1010 s-1. We found a kinetic isotope effect of about 2.5 for this process. The deprotonated form of d-luciferin in the excited state recombines irreversibly with the geminate proton. Hence, the fluorescence decay of the deprotonated form is nonexponential, and the fluorescence quantum yield is low.
Original language | English |
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Pages (from-to) | 8075-8082 |
Number of pages | 8 |
Journal | Journal of Physical Chemistry A |
Volume | 114 |
Issue number | 31 |
DOIs | |
State | Published - 12 Aug 2010 |