RADIOLYSIS AND PHOTOIONIZATION IN CLOSED ORGANIZED MEDIA - INFLUENCE OF THE INTERFACES

Various reported radiolysis and photoionization experiments have made use of the valuable specific properties of micelles and vesicles. The influence of a charged interface separating the aqueous and lipid phas es is now emphasized. The latter affects the ''free'' or ''bound'' sta te of the water molecules adjacent to the interface, the photoinduced charge separation as well as the neutralization thermal reactions. Rea ctions of the water radiolysis products and of oxygen in the presence of organized media are considered and shown to require a nonhomogeneou s treatment. From the various data examined, it appears that: the conc lusions drawn from homogeneous solution radiolysis cannot be directly extrapolated to heterogeneous biological media; the stuctural and func tional analogy which exists between synthetic micelles and vesicles an d cell membranes allows a better approach to the radiochemical behavio r of bioagregates.