Raman spectroscopic study of calf thymus DNA:: an effect of proton- and γ-irradiation

Raman spectroscopy was applied to analyse structural changes in calf thymus double-stranded deoxyribonucleic acid (dsDNA) after proton- and gamma-irradiation (0.5, 5 and 50 Gy). Characteristic Raman bands of phosphodiester linkages, nucleic bases and deoxyribose moieties were sensitive to irradiation. A significant damage of the macromolecules was observed only at the highest dose (50 Gy) of both types of radiations. Spectral changes confirmed a radiation-induced alteration of the native structure of dsDNA. Nucleic bases, especially pyrimidines, were the most sensitive to radiation, while some alterations in the sugar-phosphate backbone were also detected. The differences in the dose-dependent effects of proton vs gamma-irradiation on studied biomolecule are discussed. Copyright (C) 2007 John Wiley & Sons, Ltd.