Michael W. Allen, Jay R. Unruh, Brian D. Slaughter
Jul 2, 2003
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0
Influential Citations
12
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Journal
Journal of Physical Chemistry A
Abstract
This paper presents a detailed description of the fluorescence and photophysical behavior of indoline and indoline-2-carboxylic acid (I2CA). Indoline is an analogue of indole lacking the C2C3 double bond, but unlike indole, indoline possesses well-separated 1La and 1Lb states. I2CA, which displays similar fluorescence properties, is an amino acid and can be regarded as a fluorescent analogue of proline. In view of the potential for indoline and I2CA as fluorescent probes in peptides and proteins, we have undertaken an in-depth study of the spectroscopic and photophysical properties of these molecules. A companion paper (Slaughter, B.D.; Allen, M. W.; Lushington, G. H.; Johnson, C. K. J. Phys. Chem. A 2003, 107, 5670) presents a theoretical treatment of the spectroscopic transitions of indoline and I2CA. The pH-dependent absorption and fluorescence characteristics are investigated for both indoline and I2CA. Ground- and excited-state dissociation constants are determined spectroscopically. Quantum yields a...