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放线菌素D是一种和双链DNA和单链DNA都能发生选择性结合的抗生素,而这种结合作用大大增加了DNA的光敏性.利用电子顺磁共振（EPR）和自旋捕捉技术,对放线菌素D光动力作用过程中产生的活性氧进行了系统研究,发现无论是在溶液中还是在与DNA形成复合物以后,1_(O_2)和O_2-都是重要的活性产物,而且两者的产额存在竞争关系.实验结果说明,放线菌素D的光敏作用是通过能量转移（Ⅱ型机制）和电子转移（Ⅰ型机制）两种反应途径进行的.当在溶液中氧自由存在时,以能量转移形成1_(O_2)为主;而当和DNA形成复合物时,放线菌素D的激发态与DNA之间的电子转移反应成为主要的反应途径.
Actinomycin D is an antibiotic that selectively binds both double-stranded DNA and single-stranded DNA, and this binding greatly increases the photosensitivity of DNA. Electron paramagnetic resonance (EPR) and spin-capture Technology, the active oxygen generated during the photodynamic action of actinomycin D was studied systematically and found that both O_ (2) and O_ (2) are important active products in the solution or after forming complexes with DNA , And there is a competitive relationship between the two.The experimental results show that the actinomycin D photosensitization through the energy transfer (Ⅱ mechanism) and electron transfer (Ⅰ mechanism) two reaction pathways when in solution When oxygen is free, 1_ (O_2) is mainly formed by energy transfer. When the complexes with DNA are formed, the reaction between actinomycin D and the electron transfer between DNA and DNA becomes the main reaction pathway.