Abstract
Concentration is a key determining factor in the fluorescence properties of organic fluorophores. We studied self-quenching of disodium fluorescein (uranin) fluorescence in polyvinyl alcohol (PVA) thin films. The concentration dependent changes in brightness and anisotropy were followed by a lifetime decrease. We found that at a concentration of 0.54 M, the lifetime decreases to 7 ps. At a concentration of 0.18 M the lifetime was 10 ps with the relatively high quantum yield of 0.002. In these conditions the fluorescence intensity decay was homogeneous (well approximated by a single lifetime). We realized that such a sample was an ideal fluorescence lifetime standard for spectroscopy and microscopy, and therefore characterized instrument response functions for a time-domain technique. We show that self-quenched uranin enables measurements free of the color effect, making it a superior choice for a lifetime reference over scattered light.
Original language | English |
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Pages (from-to) | 2446-2451 |
Number of pages | 6 |
Journal | Journal of Luminescence |
Volume | 130 |
Issue number | 12 |
DOIs | |
State | Published - Dec 2010 |
Keywords
- Homo-FRET
- Homotransfer
- Instrument response function
- Lifetime standard
- Self-quenching
- Single photon avalanche diode