Radiation induced electron transfer between histone H3 and some hydroxycinnamic acid derivatives within binary molecular aggregates has been in vestigated by means of resolution and simulation of ESR spectra from those aggregates γ-irradiated and recorded at 77K

respectively. The excellent linear relationships

which were made on the basis of simulation of composite ESR spectra relevant to those binary aggregates with various molar ratios of the two components

between spin transfer ratios(Rsc) and molar ratios (r) of the aggregates indicate that those hydroxycinnamic acid derivatives have effective potential for repair of the radiation damaged protein by abstracting electrons on peptide carbonyl radical anions in protein. These results are in good accord with our previous studies on radiation protection of DNA and proteins via charge transfer from the damaged biomolecules to hydroxycinnamic acid derivatives. The hydrogen bond formed between peptide carbonyl in protein and phenolic hydroxyl of hydroxycinnamic acids within the aggregates has been illustrated as the major pathway for electron transfer from H3 to caffeic acid hased upon pH dependence on the linear relationship between Rsc and r of irradiated histone H3-caffeic acid aggregates.