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arXiv · 0911.4651

Photogenerated singlet oxygen damages cells in optical traps

S. D. Zakharov N. C. Thanh
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Abstract

The origin of photodamage of single cells confined in laser tweezers is determined by comparison of action spectra with these recorded for a photoinduced response of cell populations. Triplet-singlet transitions in dissolved oxygen provide a common cause of both phenomena. Such transitions are forbidden in isolated O2 molecules, but occur in solutions due to the formation of temporary oxygen-solvent complexes. In dependence on the photon energy oxygen molecules may be excited alone or in combination with roto-vibrational excitations in H2O. The photodamage is a consequence of a toxic action produced by the singlet oxygen 1O2 (1.DELTA.gO2.).

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S. D. Zakharov N. C. Thanh. 2009-11-24. Photogenerated singlet oxygen damages cells in optical traps. https://arxiv.org/abs/0911.4651

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