Wan, X. S., Bloch, P., Ware, J. H., Zhou, Z., Donahue, J. J., Guan, J., Stewart, J. and Kennedy, A. R. Detection of Oxidative Stress Induced by Low- and High-Linear Energy Transfer Radiation in Cultured Human Epithelial Cells. Radiat. Res. 163, 364–368 (2005).

A standardized dichlorofluorescin (DCF) fluorometric assay capable of measuring radiation-induced oxidative stress was used to determine the effectiveness of protons and high-mass, high-atomic number (Z) and high-energy (HZE) particles to produce oxidative stress in vitro. Protons were found to be about equally as effective as X rays in the generation of oxidative stress in cultured cells. However, ⁵⁶Fe-ion beams with energies of 1 GeV/nucleon and 5 GeV/nucleon were less effective than X rays or γ rays in inducing dichlorofluorescin (DCFH) oxidation. The relatively lower slope values for the dose responses of HZE-particle radiation-induced DCFH oxidation indicate that the sensitivity of the DCF fluorometric assay is probably dependent on the linear energy transfer (LET) of the radiation beam.