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arXiv · 1006.0358

Effect of intense, ultrashort laser pulses on DNA plasmids in their native state: strand breakages induced by {\it in-situ} electrons

J. S. D'Souza·J. A. Dharmdhikari·A. K. Dharmdhikair·B. J. Rao·D. Mathur
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Abstract

Single strand breaks are induced in DNA plasmids, pBR322 and pUC19, in aqueous media by intense ultrashort laser pulses (820 nm wavelength, 45 fs pulse duration, 1 kHz repetition rate) at intensities of 1-12 TW cm$^{-2}$. The intense laser radiation generates, {\it in situ}, electrons that induce transformation of supercoiled DNA into relaxed DNA. The extent of electron-mediated relaxation of DNA structure is quantified. Introduction of electron and radical scavengers inhibits DNA damage.

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J. S. D'Souza, J. A. Dharmdhikari, A. K. Dharmdhikair, B. J. Rao, D. Mathur. 2010-06-02. Effect of intense, ultrashort laser pulses on DNA plasmids in their native state: strand breakages induced by {\it in-situ} electrons. https://arxiv.org/abs/1006.0358

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