Impact of Protons on Biomolecular Systems

B. Farizon, M. Farizon

Groupe Interactions Particules Matière (IPM) Institut de Physique Nucléaire de Lyon 4, rue Enrico Fermi, Bât. Paul Dirac 69622 Villeurbanne, France
Tél : + 33 (0)472448401/+ 33 (0)472448389 Fax : +33 (0)472448004


Research interests

The experiment developed by the IPM group is focus upon the impact of protons on biomolecular targets at velocities of the order of the Bragg peak (c/137). Incident protons of velocity within the range of the Bragg peak are known to dramatically degrade the reparability of DNA. Proton therapy techniques apply this effect to destroy cancerous cells localised within internal tumours. The treatment is based upon the assumption that the damage to living cells caused by proton impact at velocities below the Bragg peak is negligible. The experiment will provide key results to advance the understanding of the molecular mechanisms underlying the degradation processes. By targeting biomolecules both in the gas phase and within clusters of water molecules, the project will contribute to the clarification and quantification of the distinction between the direct and indirect effects of ionising radiation. Beyond the value of such understanding for cancer therapy, research of this kind is of particular importance for the evaluation of the effects on living material of low doses of ionising radiation. While the damage caused by high doses is relatively well documented, the effects of low doses cannot be assessed reliably by direct observation alone. Therefore, accurate models need to be developed on the basis of the specific mechanisms by which an incident radiation can cause damage to biological systems and the associated cross sectional data. Following the completion of the apparatus, the project will feature absolute cross-section measurements for the production of specific ionic fragments following high-velocity collisions between protons and biological targets. Thus, the fragmentation mechanisms and reactions within a cluster will be studied for a selection of key biomolecules as a function of the number of surrounding water molecules.

COST P9 Workings group(s) of interest: WG1