Chain reactions and radiosensitization: model enzyme studies.

The influence of persulphate ions on the radiosensitivity of dilute aqueous solutions of ribonuclease and lysozyme has been studied under a variety of conditions. Rate-constants for reactions of the sulphate radical, SO4, with a variety of solutes and transient product spectra of some of these reactions are reported. The presence of persulphate ions in general enhances the radiation sensitivity; in nitrous-oxide-saturated persulphate solution, a chain reaction has been demonstrated.