Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution—1: Beam quality and concentration dependences

• Published in: Radiation physics and chemistry (Oxford, England : 1993) Vol. 80; no. 4; pp. 535 - 539
• Main Authors: Maeyama, Takuya, Yamashita, Shinichi, Baldacchino, Gérard, Taguchi, Mitsumasa, Kimura, Atsushi, Murakami, Takeshi, Katsumura, Yosuke
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2011
• Subjects: Absorption spectroscopy; Beams (radiation); Conversion; Coumarin-3-carboxylic-acid; Extreme values; Fluorescence; Fluorescent probe; Ion beam; Ion beams; LET; OH yield; Radiolysis; Scavenging; Water radiolysis; Ion beam; Coumarin-3-carboxylic-acid; LET; OH yield; Water radiolysis; Fluorescent probe
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/j.radphyschem.2010.11.013

Aqueous coumarin-3-carboxylic acid (3-CCA) solutions were irradiated with seven different ion beams covering LET range from 0.5 to above 2000eV/nm. G-values of 7OH-CCA, one of hydroxylated products in radiolysis of the solutions, have been determined by fluorescence-HPLC technique in 3-CCA concentration range from 0.1 to 26mM. The formation yield of 7OH-CCA increased with increase in concentration of 3-CCA while it decreased with increase in LET value of ion beam. Compared with our previous reports on G(•OH) at a scavenging capacity of 107s−1 with absorption spectroscopy, it was found that G(7OH-CCA) is about (4.7±0.6)% of G(•OH), which is consistent for all of the ion beams used in the present study. However, 7OH-CCA yields in high 3-CCA concentration region, especially by using extremely high LET ions, were much higher than expected values based on the above conversion factor and G(•OH) value predicted in theoretical work.