Abstract |
Time-resolved measurements were made of near-infrared emission from 5-(N-hexadecanoyl)amino-eosin-labeled L1210 leukemia cells following pulsed-laser excitation. The cells were suspended in phosphate-buffered saline made with deuterium oxide solvent. A significant fraction of the emission occurring 10-80 microseconds after the laser pulse was due to singlet oxygen. This singlet-oxygen emission is believed to result from singlet oxygen generated near the cell-membrane surface, where 5-(N-hexadecanoyl)amino eosin is known to concentrate, and then diffusing out into the buffer. The intensity and the kinetics of the experimentally observed singlet-oxygen emission were in excellent agreement with the predictions of a theoretical one-dimensional model of singlet-oxygen diffusion and quenching. During the 10-80 microseconds time period studied, most of the singlet oxygen was located in the buffer. Thus, the use of water-soluble singlet-oxygen quenchers, such as histidine, provide one means of separating the singlet-oxygen emission from other sources of light during this time interval.
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Authors | A Baker, J R Kanofsky |
Journal | Photochemistry and photobiology
(Photochem Photobiol)
Vol. 57
Issue 4
Pg. 720-7
(Apr 1993)
ISSN: 0031-8655 [Print] United States |
PMID | 7685124
(Publication Type: Comparative Study, Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
- Photosensitizing Agents
- 5-(N-hexadecanoyl)aminoeosin
- Singlet Oxygen
- Histidine
- Carnosine
- Ascorbic Acid
- Oxygen
- Eosine Yellowish-(YS)
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Topics |
- Animals
- Ascorbic Acid
(pharmacology)
- Carnosine
(pharmacology)
- Cell Membrane
(metabolism)
- Diffusion
- Eosine Yellowish-(YS)
(analogs & derivatives, metabolism, pharmacology)
- Histidine
(pharmacology)
- Kinetics
- Leukemia L1210
(metabolism)
- Mice
- Models, Biological
- Oxygen
(metabolism)
- Photochemistry
- Photosensitizing Agents
(pharmacology)
- Singlet Oxygen
- Time Factors
- Tumor Cells, Cultured
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