Molecular Mass and Volume in Radiation Target Theory

Abstract

Radiation target analysis is based on the action of ionizing radiation directly on macromolecules. Interactions of this radiation with the molecules leads to considerable structural damage and consequent loss of biological activity. The radiation sensitivity is dependent on the size of the macromolecules. There has been confusion and discrepancy as to whether the molecular mass or the molecular volume was the determinant factor in the sensitivity. Some proteins are known to change their hydrodynamic volume at low pH, and this characteristic can be utilized to compare the radiation sensitivities of these proteins in the two states. The results show that the radiation sensitivity of proteins depends on the mass of the molecule and is independent of the molecular volume/shape.

Inactivated virus vaccines from chemistry to prophylaxis: merits, risks and challenges

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“…40 This phenomenon is ascribed to damage propagation throughout the protein consequent to a single hit. A radiation target method, using semi-quantitative measures of DNA damage on agarose gels, for estimating the size of supercoiled plasmid DNA was reported recently.…”

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