pulse radiolysis study of radicals formed by oxidation of acetamiophen.

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The semi-iminoquinone radical of acetaminophen, which has previously been proposed as a possible hepatotoxic intermediate in the cytochrome P catalysed oxidation of acetaminophen, has been generated and studied by pulse by:   Abstract Free radicals from one-electron oxidation of the antimalarial drug pyronaridine have been studied by pulse radiolysis.

The results show that pyronaridine is readily oxidised to an intermediate semi-iminoquine radical by inorganic and organic free radicals, including those derived from tryptophan and by: 4. Free radicals from one-electron oxidation of the antimalarial drug pyronaridine have been studied by pulse radiolysis.

The results show that pyronaridine is readily oxidised to an intermediate. The oxidation of Br- by Cl2- is investigated by gamma pulse radiolysis in aqueous solutions of NACl and NaBr. Depending on the ratio of the concentration of Br- to Cl- the main product being.

The dynamics of free‐radical species in a model cellular system are examined by measuring the formation and decay of ascorbate radicals within a liposome with pulse radiolysis techniques.

Upon pulse radiolysis of an N2O‐saturated aqueous solution containing ascorbate‐loaded liposome vesicles, ascorbate radicals are formed by the reaction of ls with ascorbate in unilamellar vesicles. Free radicals from one-electron oxidation of the antimalarial drug pyronaridine have been studied by pulse radiolysis.

The results show that pyronaridine is readily oxidised to an intermediate semiiminoquine radical by inorganic and organic free radicals, including those derived from tryptophan and acetaminophen. The dynamics of free‐radical species in a model cellular system are examined by measuring the formation and decay of ascorbate radicals within a liposome with pulse radiolysis techniques.

Upon pulse radiolysis of an N 2 O‐saturated aqueous solution containing ascorbate‐loaded liposome vesicles, ascorbate radicals are formed by the Author: Kazuo Kobayashi, Yumiko Seike, Akinori Saeki, Takahiro Kozawa, Fusako Takeuchi, Motonari Tsubaki.

Pulse radiolysis studies have previously been used to study the redox behaviour of phenols and aminophenols and the properties of the phenoxyl and semi(imino)quinone radicals formed by oneelectron oxidation[20,21]. Free radicals from one-electron oxidation of the antimalarial drug pyronaridine have been studied by pulse radiolysis.

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The results show that pyronaridine is readily oxidised to an intermediate semi-iminoquine radical by inorganic and organic free radicals, including those derived from tryptophan and by: 4. THE REACTIONS OF HYDROXYL RADICAL WITH SOME TRANSITION-METAL COMPOUNDS CONTAINING ORGANIC MOLECULES. Photochemistry and Photobiology28 (), DOI: /jtbx.

P Wardman. Application of pulse radiolysis methods to study the reactions and structure of by: 1. Pulse radiolysis has been used to measure directly the absolute rates of oxidation by ferricyanide ion of various radicals produced by OH attack on organic solutes.

These include mono, di- and polyhydroxylic compounds, hydroxy acids, polyethylene oxides of molecular weightand 20 and the amino acid serine.

The yield of benzyl radical (Bz) formed by electron‐beam pulse radiolysis of benzyl chloride (BzCl) in cyclohexane vapor ( atm/°) has been studied by optical absorption measurements. Electron scavengers lower the benzyl radical (Bz) absorption by competing with dissociative electron capture by BzCl.

A study of this competition gave the relative rate constants for Cited by: 9. The reaction of hydroxyl radical (• OH) with the nucleic acid base analogue 2-thiouracil (1) has been studied by pulse radiolysis experiments and generic intermediate radicals feasible for the • OH reactions with 1, namely, one electron oxidation product (1 •+), • OH-adducts (3 •, 4 •, and 5 •), and H-abstracted radicals (6 • and 7 •), were characterized by.

Description pulse radiolysis study of radicals formed by oxidation of acetamiophen. EPUB

A pulse radiolysis study of glutathione in aqueous solution at pH 55 containing N 2 O/O 2 mixtures at various ratios indicates that oxygen rapidly adds to the thiyl glutathione radical yielding a transient absorption, with a maximum at nm, whose characteristics appear to be compatible with assignment to the GSOO radical.

The reaction appears to be an equilibrium whose kinetic Cited by: by using two methods: gamma and pulse radiolysis. We carried out the gamma radiolysis experiments with + PBq ( TBq) activity of 60Co γ-source.

The pulse radiolysis is a unique tool for creating OH radicals and other strong oxidants in water medium and for studying their reactions. The technique uses short pulse of accelerated electrons.

free radicals on real time. The selected contributions of pulse radiolysis to better understanding the role of free radical reactions in chemistry, biology and medicine are presented and some selected future research needs and opportunities in radiation chemistry are briefly addressed.

Key words free radicals • pulse radiolysis • oxidative. The radical anion, Br 2 ˙–, a strong one-electron oxidant, has been used to oxidise iron(II)–imidazole, Fe II –ImH, and iron(II)–bis(imidazolyl)methane, Fe II –2-BIM, complexes in aqueous solution, the latter being regarded as good models of the iron(II) site in non-haem iron-containing enyzmes such as rates of oxidation of Fe II –lmH, Fe II (ImH) 2, Fe–2-BIM.

Abstract Pulse radiolysis and laser-flash photolysis have been used to generate the radicals SO -2, SO -3, SO -4 and SO Optical absorption spectra for these radicals and rate constants for their self-reactions have been derived.

The radiolysis of water due to ionizing radiation results in the production of electrons, H atoms, OH radicals, H3O+ ions and molecules (dihydrogen H2 and hydrogen peroxide H2O2). A brief history of the development of the understanding of water radiolysis is presented, with a focus on the H2 production.

This H2 production is strongly modified at oxide by: A mechanistic pulse radiolysis study}, author = {Goldbach, A and Saboungi, M L and Johnson, J A and Cook, A R and Meisel, D}, abstractNote = {The oxidation of aqueous polyselenide solutions was studied by pulse radiolysis in the presence of N{sub 2}O at pH ; the hydroxyl radical OH was the predominant oxidant, while hydrogen selenide anions.

Solutions of SH can be photolyzed also with nm laser pulses to produce the SH/ S / S radical. The same radical is formed by oxidation of SH ions with SO 4. and CO 3 radicals. At pH > 5 SH/ S reacts with SH (k f = 4 x 10 9 L mol s, k r = 5 x 10 5 s) to form HSSH.-/HSS, with λ max at by: @article{osti_, title = {Formation of peroxynitrite from the oxidation of hydrogen peroxide by nitrosonium ion (NO{sup +}): A pulse radiolysis study}, author = {Goldstein, S and Czapski, G}, abstractNote = {The rate constant of the reaction of {sup {sm_bullet}}N{sub 3} with {sup {sm_bullet}}NO has been determined to be ( {+-} ) x 10{sup 9} M{sup -1} s{sup -1} using the pulse.

Pulse radiolysis and polarography. pH dependence of the oxidation and reduction potentials of short-lived organic radicals at the dropping mercury electrodeAuthor: M.

Graetzel, A. Henglein, J. Lilie, M. Scheffler. In the present study, we used both time-resolved (pulse radiolysis) and steady-state (using a Fenton system) analyses of the reaction of HE with O 2 s show that O 2 -reacts fairly rapidly with HE and that O 2 -generated from hydroxyl radicals ( OH) reacts with HE to form the characteristic product, 2-OH-E +.We have also demonstrated that the one-electron oxidation species Cited by:   Applications of Pulse Radiolysis to Protein Chemistry - Volume 12 Issue 4 - M.

Klapper, M. Faraggi Pulse Radiolysis studies of the oxidation of phenols by SO 4 – and Br 2 – in aqueous solutions. Mechanism of tryptophan oxidation by some inorganic radical-anions: a pulse radiolysis study. by: Chemiluminescence as a Means to Study the Role of Hydroxyl Radicals in Oxidative Processes The latter process is often catalyzed by transition metal ions (Walling ).

A convenient method of producing hydroxyl radicals in dilute aqueous solution is by decomposition of the solvent using ionizing radiation (Baxendale and Busi ).

Pulse radiolysis in study of oxygen radicals. (PMID) Abstract Citations; Related Articles; Data; BioEntities; External Links ' ' Simic MG Methods in Enzymology [01 Jan] Type: Journal Article DOI: /(90)c. Abstract. No abstract provided.

Cited by: Abstract Reactions of hydroxyl radicals (*OH) with selenocystine (SeCys) and two of its analogues, diselenodipropionic acid (SeP) and selenocystamine (SeA), have been studied in aqueous solutions at pHs of 1, 7, and 10 using the pulse radiolysis technique coupled with absorption detection.

Reduction Potential of the Sulfhydryl Radical: Pulse Radiolysis and Laser Flash Photolysis Studies of the Formation and Reactions of SH and HSSH-in Aqueous Solutions Abstract Not Available Bibtex entry for this abstract Preferred format for Return: Query Results: Return items starting with number: Query Form: Database: Astronomy.

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Details pulse radiolysis study of radicals formed by oxidation of acetamiophen. PDF

t1 - pulse radiolysis studies on the mechanism of the high sensitivity of chloromethylated polystyrene as an electron negative resist. au - tabata, y. au - tagawa, s. au - washio, m. py - /12/1. y1 - /12/1Cited by: Radiolysis is the dissociation of molecules by ionizing is the cleavage of one or several chemical bonds resulting from exposure to high-energy flux.

The radiation in this context is associated with ionizing radiation; radiolysis is therefore distinguished from, for example, photolysis of the Cl 2 molecule into two Cl-radicals, where (ultraviolet or visible spectrum) light is used.the H can interact with molecular oxygen to form the hydroperoxyl radical H + O>HO2.

HO 2 + HO >H2O2 +O2 some organic molecules can become reactive free radicals (r=one part of CHON).