Kahnt A, Guldi DM, Brettreich M, Hartnagel U, Hirsch A (2010)
Publication Type: Journal article, Original article
Publication year: 2010
Original Authors: Kahnt A., Guldi D.M., Brettreich M., Hartnagel U., Hirsch A.
Publisher: Royal Society of Chemistry
Book Volume: 20
Pages Range: 83-89
Journal Issue: 1
DOI: 10.1039/b917346n
In this work we focused on the reaction of water-soluble fullerene derivatives with various organic (i.e., methyl radical and t-butyl radical) and inorganic (i.e., superoxide radical and azide radical) radicals to mimic their superoxide dismutase (SOD) activity. Importantly, with the help of time-resolved pulse radiolysis and steady-state gamma radiolysis measurements all of the assays were conducted in aqueous solutions. Our fully-fledged spectroscopic and kinetic investigations leave no doubt about a diffusion-controlled addition mechanism (10 M s) by which superoxide radical reacts with fullerenes to yield (C-O) . Notable is that the formations of (C-CH), (C-(CH)(CH)COH), and (C -N) are much slower and proceed with activation-controlled rate constants less than 10 M s. The major deactivation path of (C-O ) is a pH dependent protonation (10 M s). Despite lacking unambiguous evidence for the formation of C - via a direct impact or an indirect dissociation mechanism - (C-O) is still redoxactive. The latter has been confirmed by an activation-controlled reduction (10 M s) of a series of p-benzoquinones that display different electron affinities. In other words, (C -O) - but not C - is likely to emerge as a key intermediate in the SOD activity of fullerenes. Its slow protonation is beneficial toward an efficient dismutation to form H O. © 2010 The Royal Society of Chemistry.
APA:
Kahnt, A., Guldi, D.M., Brettreich, M., Hartnagel, U., & Hirsch, A. (2010). Reaction of water-soluble fullerenes with O2 - and other reactive radical species. Journal of Materials Chemistry, 20(1), 83-89. https://dx.doi.org/10.1039/b917346n
MLA:
Kahnt, Axel, et al. "Reaction of water-soluble fullerenes with O2 - and other reactive radical species." Journal of Materials Chemistry 20.1 (2010): 83-89.
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