Free radical mechanism in enhancement of radiosensitization by SRSBR.

The free radical mechanism of enhancing radiosensibility by the Synergic Recipe to Strengthen Body Resistance (SRSBR) consisting of 10 Chinese drugs was studied by electron spin resonance (ESR) with spin trapping reagent--Nitroso-tert-butane (NtB) following irradiation of the Deoxy thymidine (dT) solution system by 60Co 3.7 PBq. The results showed SRSBR cannot only enhance the generation of e- aq but also enhance the production of . OH and H . after irradiation with gamma ray in dT-NtB-SRSBR aqueous solution system. These result in damage to biological molecules, attacking and killing tumor cells radiosensitized by SRSBR. The characteristics of SRSBR for radiosensitization are concluded to be increasing production of . OH and H. in comparison with the well-known radiosensitizer-Misonidazole (Miso).