What Is A Free Radical - Ústav lékařské chemie a biochemie

Hydroxyl radical
• Formation in the body:
– Ionising radiation:
H 2 O → H· + OH·
OH ·
– The Fenton reaction:
H 2 O 2 + Fe 2+ → OH – + OH· + Fe 3+
• Properties:
- Extremely high reactivity. Damages biomolecules
near its site of formation.
Reactive Oxygen Species (ROS)
• Radicals:
– Superoxide, O 2·–
– Hydroperoxyl radical, HO 2·
– Hydroxyl radical, OH·
– Peroxyl radicals, ROO·
– Alkoxyl radicals, RO·
• Non-radicals:
– Hydrogen peroxide, H 2 O 2
– Hypochlorous acid, HClO
– Ozone O 3
– Singlet oxygen, 1 O 2
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