Radiolysis of phenylalanine in solution with Bragg-Peak energy protons

N. Ludwig (1) , T. Kusumoto (1) , C. Galindo (1) , P. Peaupardin (1) , S. Pin (2) , J.-P. Renault (2) , D. Muller (3) , T. Yamauchi (4) , S. Kodaira (5) , R. Barillon (1) , Q. Raffy (1)

1 IPHC - Institut Pluridisciplinaire Hubert Curien
2 LIONS - Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire
3 ICube - Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie
4 Faculty of Maritime Sciences
5 NIRS - National Institute of Radiological Sciences

Phenylalanine aqueous solutions were irradiated with Bragg-Peak energy protons (0.6–5.6 MeV). An innovative circulation setup has been developed for the irradiation of these solutions with low-energy protons. Every detectable radiolysis product has been identified and quantified after irradiation. While tyrosines are well-known products of phenylalanine radiolysis, 2,5-dihydroxyphenylalanine and dimers were detected in high quantities, for the first time. The track-yields (G'-values) of all products formed under proton irradiation were determined and compared to those obtained with gamma-rays, and 2,5-dopa and dimers production seems to be specific to accelerated ions. A bi-radical mechanism could explain their higher production with a higher density of energy deposition in the track structure.

Domains: Material chemistry

N. Ludwig, T. Kusumoto, C. Galindo, P. Peaupardin, S. Pin, et al.. Radiolysis of phenylalanine in solution with Bragg-Peak energy protons. Radiation Measurements, 2018, 116, pp.55 - 59. ⟨10.1016/j.radmeas.2018.07.007⟩. ⟨cea-01855331⟩