Ionisation clusters at DNA level: experimental modelling.

S Pszona; J Kula

doi:10.1093/oxfordjournals.rpd.a006813

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Ionisation clusters at DNA level: experimental modelling.

S Pszona·J Kula

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Abstract

The importance of initial clustered damage to DNA is a hypothesis, which has to be approached also from physical modelling of the initial products of single charged particle interaction with DNA. A new tool for such studies, presented here, is based on modelling of the ionisation patterns resulting from a single charged particle crossing a nitrogen cavity of nanometre size. The nanometre size sites equivalent in unit density to DNA and nucleosome, have been modelled in a device, called a Jet Counter, consisting of a pulse operated valve which injects nitrogen in the form of an expansion jet into an interaction chamber. The distributions of the number of ions in a cluster created by a single alpha particle of 4.6 MeV along 0.15 nm to 13 nm size in nitrogen have been measured. A new descriptor of radiation action at DNA level is proposed.

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DNA DNA Damage Electrons Models, Theoretical Monte Carlo Method Radiation, Ionizing Radiometry Sensitivity and Specificity Journal Article Research Support, Non-U.S. Gov't

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S Pszona, J Kula. 2002. Ionisation clusters at DNA level: experimental modelling.. https://doi.org/10.1093/oxfordjournals.rpd.a006813

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