Visualization Reactive oxygen species

Photodynamic therapy uses non-thermal red light to activate verteporfin, which produces reactive oxygen species that locally damage the neovascular endothelium.24 Verteporfin treatment reduces the risk of loss of visual acuity and legal blindness over 1 to 2 years. Long-term results are not yet available. Severe photosensitivity for 3 to 5 days after the procedure is common and some patients experience a severe loss of vision. Eventually, most patients have some visual recovery. This procedure requires multiple treatments over time.22... 

Szilagyi, G. Simon, L. Koska, R Telek, G. Nagy, Z. Visualization of mitochondrial membrane potential and reactive oxygen species via double staining. Neurosci. Lett. 2006, 399, 206-209. 

It is considered that tissue injury following ischemia and reperfusion is mediated by reactive oxygen derived-species (ROS) and pools of redox active iron and copper. The role of free iron and copper is visualized mainly as causing the conversion of low reactive species, such as superoxide radical anion, to the highly reactive hydroxyl radicals. The significance of iron in ischemia and reperfusion is supported by studies showing that metal chelation protected post-ischemic tissue [8], whereas the addition of iron to the perfusate increased the rate of injury [9]. 

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