Matches in SemOpenAlex for { <https://semopenalex.org/work/W2060837415> ?p ?o ?g. }
- W2060837415 endingPage "1338" @default.
- W2060837415 startingPage "1330" @default.
- W2060837415 abstract "The spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) is frequently used to identify free radicals that are generated photochemically using dyes as photosensitizers. When oxygen is present in such systems, singlet oxygen (1O2) may be produced and can react with DMPO. We have studied the reaction of DMPO with 1O2 in aqueous solutions over a wide range of pH, using micellar Rose Bengal (pH 2−13) and anthrapyrazole (pH < 2) as photosensitizers. We found that DMPO quenches 1O2 phosphorescence (kq = 1.2 × 106 M-1 s-1), thereby initiating oxygen consumption that is slow at pH 10 but increases about 10-fold at pH < 6. This oxygen consumption is a composite process that includes efficient oxidation of both DMPO and its degradation products. The oxidation products include both products in which the DMPO pyrroline ring remains intact (DMPO/•OH and 5,5-dimethyl-2-oxo-pyrroline-1-oxyl (DMPOX) radicals) and those in which it becomes opened (nitro and nitroso products). The nitroso product itself strongly quenched 1O2 phosphorescence, while (photo)decomposition of the nitroso group, presumably to nitric oxide (NO•), produced nitrite as a minor product. We propose that 1O2 adds to the >CN(O) bond in DMPO, producing a biradical, >C(OO•)N•(O). This biradical may follow one of two pathways: (i) It may be protonated and rearrange to a strongly oxidizing nitronium-like moiety, which could be reduced to the DMPO hydroperoxide radical DMPO/•O2H while oxidizing another DMPO moiety to ultimately form DMPOX. The DMPO/•O2H could undergo further redox decomposition, e.g. via the known Fenton-like reaction, to produce both free •OH radical and the DMPO/•OH radical. (ii) The biradical >C(OO•)N•(O) may cyclize to a 1,2,3-trioxide (ozonide), which could open the pyrroline ring to form 4-methyl-4-nitropentan-1-al and 4-methyl-4-nitrosopentanoic acid. Because the oxidation of DMPO by 1O2 leads to both rapid O2 depletion and the formation of transients and products that might interfere with trapping and identification of free radicals, DMPO should be used with caution in systems where 1O2 is produced." @default.
- W2060837415 created "2016-06-24" @default.
- W2060837415 creator A5002881154 @default.
- W2060837415 creator A5009588063 @default.
- W2060837415 creator A5066234326 @default.
- W2060837415 creator A5087992186 @default.
- W2060837415 date "1996-01-01" @default.
- W2060837415 modified "2023-10-14" @default.
- W2060837415 title "Oxidation of the Spin Trap 5,5-Dimethyl-1-pyrroline <i>N</i>-Oxide by Singlet Oxygen in Aqueous Solution" @default.
- W2060837415 cites W1968387897 @default.
- W2060837415 cites W1983198076 @default.
- W2060837415 cites W1986319436 @default.
- W2060837415 cites W1992915741 @default.
- W2060837415 cites W1998272209 @default.
- W2060837415 cites W2004490214 @default.
- W2060837415 cites W2014822973 @default.
- W2060837415 cites W2017303691 @default.
- W2060837415 cites W2022377100 @default.
- W2060837415 cites W2026849188 @default.
- W2060837415 cites W2027790836 @default.
- W2060837415 cites W2030699870 @default.
- W2060837415 cites W2042574369 @default.
- W2060837415 cites W2054059522 @default.
- W2060837415 cites W2054198329 @default.
- W2060837415 cites W2054226158 @default.
- W2060837415 cites W2056979802 @default.
- W2060837415 cites W2057198055 @default.
- W2060837415 cites W2060128690 @default.
- W2060837415 cites W2060277762 @default.
- W2060837415 cites W2064450459 @default.
- W2060837415 cites W2068765991 @default.
- W2060837415 cites W2070515927 @default.
- W2060837415 cites W2076850531 @default.
- W2060837415 cites W2099994130 @default.
- W2060837415 cites W2115999167 @default.
- W2060837415 cites W2130037583 @default.
- W2060837415 cites W2254245178 @default.
- W2060837415 cites W2281900189 @default.
- W2060837415 cites W2315554116 @default.
- W2060837415 cites W2488551355 @default.
- W2060837415 cites W4234604396 @default.
- W2060837415 doi "https://doi.org/10.1021/ja952140s" @default.
- W2060837415 hasPublicationYear "1996" @default.
- W2060837415 type Work @default.
- W2060837415 sameAs 2060837415 @default.
- W2060837415 citedByCount "196" @default.
- W2060837415 countsByYear W20608374152012 @default.
- W2060837415 countsByYear W20608374152013 @default.
- W2060837415 countsByYear W20608374152014 @default.
- W2060837415 countsByYear W20608374152015 @default.
- W2060837415 countsByYear W20608374152016 @default.
- W2060837415 countsByYear W20608374152017 @default.
- W2060837415 countsByYear W20608374152018 @default.
- W2060837415 countsByYear W20608374152019 @default.
- W2060837415 countsByYear W20608374152020 @default.
- W2060837415 countsByYear W20608374152021 @default.
- W2060837415 countsByYear W20608374152022 @default.
- W2060837415 countsByYear W20608374152023 @default.
- W2060837415 crossrefType "journal-article" @default.
- W2060837415 hasAuthorship W2060837415A5002881154 @default.
- W2060837415 hasAuthorship W2060837415A5009588063 @default.
- W2060837415 hasAuthorship W2060837415A5066234326 @default.
- W2060837415 hasAuthorship W2060837415A5087992186 @default.
- W2060837415 hasConcept C121332964 @default.
- W2060837415 hasConcept C139066938 @default.
- W2060837415 hasConcept C145148216 @default.
- W2060837415 hasConcept C155647269 @default.
- W2060837415 hasConcept C178790620 @default.
- W2060837415 hasConcept C181817918 @default.
- W2060837415 hasConcept C184651966 @default.
- W2060837415 hasConcept C185592680 @default.
- W2060837415 hasConcept C2776568683 @default.
- W2060837415 hasConcept C2776977394 @default.
- W2060837415 hasConcept C2777516457 @default.
- W2060837415 hasConcept C30095370 @default.
- W2060837415 hasConcept C540031477 @default.
- W2060837415 hasConcept C62520636 @default.
- W2060837415 hasConcept C75473681 @default.
- W2060837415 hasConcept C77176794 @default.
- W2060837415 hasConcept C91881484 @default.
- W2060837415 hasConceptScore W2060837415C121332964 @default.
- W2060837415 hasConceptScore W2060837415C139066938 @default.
- W2060837415 hasConceptScore W2060837415C145148216 @default.
- W2060837415 hasConceptScore W2060837415C155647269 @default.
- W2060837415 hasConceptScore W2060837415C178790620 @default.
- W2060837415 hasConceptScore W2060837415C181817918 @default.
- W2060837415 hasConceptScore W2060837415C184651966 @default.
- W2060837415 hasConceptScore W2060837415C185592680 @default.
- W2060837415 hasConceptScore W2060837415C2776568683 @default.
- W2060837415 hasConceptScore W2060837415C2776977394 @default.
- W2060837415 hasConceptScore W2060837415C2777516457 @default.
- W2060837415 hasConceptScore W2060837415C30095370 @default.
- W2060837415 hasConceptScore W2060837415C540031477 @default.
- W2060837415 hasConceptScore W2060837415C62520636 @default.
- W2060837415 hasConceptScore W2060837415C75473681 @default.
- W2060837415 hasConceptScore W2060837415C77176794 @default.
- W2060837415 hasConceptScore W2060837415C91881484 @default.
- W2060837415 hasIssue "6" @default.