[1C06-10] Nano Structure Analysis by Micro-beam

[1C09] Fast heavy-ion radiation damage of biomolecules in aqueous solution using the vacuum liquid micro-jet technique

*Hidetsugu Tsuchida¹, Shinji Nomura¹, Akihiro Kajiwara¹, Takuya Majima¹, Manabu Saito¹ (1. Kyoto University)

Keywords:Radiation damage of biomolecules, Radiolysis of aqueous solution, Heavy-ion irradiation

Fast heavy-ion radiolysis of biomolecules in aqueous solution is investigated for an atomistic understanding of radiation damage to normal cells during heavy-particle beam therapy. Two types of amino acids, glycine and proline, were used as model biomaterials. Microjets of aqueous solutions under vacuum were irradiated with 4.0-MeV carbon ions corresponding to energies in the Bragg peak region. To understand the effects of the water environment on molecular damage, the yield of molecular dissociation was measured by secondary ion mass spectroscopy. The yield was significantly reduced relative to gas-phase targets. This implies that the numerous water molecules surrounding a single biomolecule act as a buffer that suppresses dissociation.