Combination of misonidazole and lipoic acid on the radiation sensitivity of Bacillus megaterium spores.

The radiation sensitizing action of a combination of misonidazole and lipoic acid was investigated in Bacillus megaterium spores at various oxygen concentrations. Lipoic acid and misonidazole were applied in two concentrations (0.1 and 1.0 mmol/l) and four combinations were prepared from them. No uniform correlation was found, neither to the combination of the compounds nor to the gas conditions. The combination of two radiation sensitizing compounds with in all probability different action mechanisms does not unequivocally enhance the radiation sensitizing effect under anoxic and hypoxic conditions.