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The hydroxyl radical can damage virtually all types of macromolecules: carbohydrates, nucleic acids , lipids (lipid peroxidation) and amino acids (e.g. conversion of Phe to m-Tyrosine and o-Tyrosine). The hydroxyl radical has a very short in vivo half-life of approximately 10 −9 seconds and a high reactivity. [5]
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula −OH and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry , alcohols and carboxylic acids contain one or more hydroxy groups.
The hydroxyl radical, Lewis structure shown, contains one unpaired electron. Lewis dot structure of a Hydroxide ion compared to a hydroxyl radical. In chemistry, a radical, also known as a free radical, is an atom, molecule, or ion that has at least one unpaired valence electron.
The hydroperoxyl radical is a weak acid and gives rise to the superoxide radical (O 2 •–) when it loses a proton: HO 2 → H + + O 2 – sometimes also written as: HO 2 • → H + + O 2 •– A first pK a value of 4.88 for the dissociation of the hydroperoxyl radical was determined in 1970. [4] The presently accepted value is 4.7. [5]
The fact that oxygen changes the radiation chemistry might be one reason why oxygenated tissues are more sensitive to irradiation than the deoxygenated tissue at the center of a tumor. The free radicals, such as the hydroxyl radical, chemically modify biomolecules such as DNA, leading to damage such as breaks in the DNA strands. Some substances ...
As hydroxyl radicals are short-lived in solution, they need to be generated upon experiment. This can be done using H 2 O 2, ascorbic acid, and Fe(II)-EDTA complex. These reagents form a system that generates hydroxyl radicals through Fenton chemistry. The hydroxyl radicals can then react with the nucleic acid molecules. [17]
A demonic California dad has been arrested for allegedly beheading his 1-year-old son Friday in an early-morning frenzy of violence that also injured his wife and her mother, according to police.
Hydroxide is a diatomic anion with chemical formula OH −. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst.