Ionizing Radiation And Natural Constituents Of Living Cells: Low-Energy Electron Interaction With Coenzyme Q Analogs

Resonance electron attachment to short-tail analogs of coenzyme Q(10)is investigated in the electron energy range 0 eV-14 eV under gas-phase conditions by means of dissociative electron attachment spectroscopy. Formation of long-lived (milliseconds) molecular negative ions is detected at 1.2 eV, but not at thermal energy. A huge increase in the electron detachment time as compared with the referencepara-benzoquinone (40 mu s) is ascribed to the presence of the isoprene side chains. Elimination of a neutral CH(3)radical is found to be the most intense decay detected on the microsecond time scale. The results give some insight into the timescale of electron-driven processes stimulated in living tissues by high-energy radiation and are of importance in prospective fields of radiobiology and medicine.