Free radical mechanisms for the oxidation of substituted ascorbates. A pulse radiolysis study of L-ascorbic acid-2-sulfate

Journal Article · Thu Sep 01 04:00:00 EDT 1983 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3576098· OSTI ID:5433739

Cabelli, D E; Comstock, D A; Bielski, B H.J.

The oxidations of L-ascorbate 2-sulfate by Br/sub 2//sup -/ and OH radicals generated in aqueous solutions (pH 4.5 to 9.5) were studied by pulse radiolysis. The (2-SO/sub 4/A)./sup -/ radical, generated in an electron transfer reaction between Br/sub 2//sup -/ and the parent compound, loses sulfate (tau approx. 500 ..mu..sec) to give ascorbate free radical (A./sup -/) with a G(A./sup -/) = 2.0. The oxidation of L-ascorbate 2sulfate by OH radicals is complex, yielding both (2-SO/sub 4/A)/sup -/ and OH radical adducts. Some of these transients subsequently yield A./sup -/. HPLC studies corroborate the overall mechanism postulated for the oxidation of L-ascorbate 2-sulfate by OH radicals.

• Research Organization: Brookhaven National Lab., Upton, NY
• OSTI ID: 5433739
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 95:3; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
ABSORPTION SPECTRA
AQUEOUS SOLUTIONS
ASCORBIC ACID
BROMINE
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
DISPERSIONS
ELEMENTS
HALOGENS
HYDROXYL RADICALS
MIXTURES
NONMETALS
OXIDATION
OXYGEN COMPOUNDS
PH VALUE
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
SOLUTIONS
SPECTRA
SULFATES
SULFUR COMPOUNDS
VITAMINS