What is Reactive Oxygen Species

Redox balance is important for maintaining physiological activities in organisms. Once the level of redox-active species is abnormal, it may destroy the balance of the internal environment or further induce biological pathological changes. Therefore, it is of great scientific significance to pay attention to the changes of redox-active species in vivo. Coordination compounds are very broad and important molecular systems that can undergo a wide variety of electronic transitions, with the charge transfer from metal to ligands and their associated excited states being particularly significant. These characteristics give coordination compounds the possibility of regulating redox reactions in vivo. After cisplatin, ruthenium complexes have been extensively studied in order to be alternative molecular systems with less toxicity to normal cells. This chapter will mainly introduce in vivo redox systems, redox process detection as well as ruthenium anti-tumor drugs for redox regulation.