| Autor: |
Jana Leppin, Rute André, Filipe Natalio, Werner E. G. Müller, Madalena Humanes, Heinz-Christoph Schröder, Wolfgang Tremel, Ron Wever, Katja Heinze |
| Přispěvatelé: |
Biocatalysis (HIMS, FNWI) |
| Jazyk: |
angličtina |
| Rok vydání: |
2011 |
| Předmět: |
|
| Zdroj: |
Advanced Functional Materials, 21(3), 501-509. Wiley-VCH Verlag |
| ISSN: |
1616-301X |
| DOI: |
10.1002/adfm.201001302 |
| Popis: |
V2O5 nanowires exhibit an intrinsic catalytic activity towards classical peroxidase substrates such as 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 3,3,5,5,-tetramethylbenzdine (TMB) in the presence of H2O2. These V2O5 nanowires show an optimum reactivity at a pH of 4.0 and the catalytic activity is dependent on the concentration. The Michaelis-Menten kinetics of the ABTS oxidation over these nanowires reveals a behavior similar to that of their natural vanadium-dependent haloperoxidase (V-HPO) counterparts. The V2O5 nanowires mediate the oxidation of ABTS in the presence of H2O2 with a turnover frequency (k(cat)) of 2.5 x 10(3) s(-1). The K-M values of the V2O5 nanowires for ABTS oxidation (0.4 mu M) and for H2O2 (2.9 mu M) at a pH of 4.0 are significantly smaller than those reported for horseradish peroxidases (HRP) and V-HPO indicating a higher affinity of the substrates for the V2O5 nanowire surface. Based on the kinetic parameters and similarity with vanadium-based complexes a mechanism is proposed where an intermediate metastable peroxo complex is formed as the first catalytic step. The nanostructured vanadium-based material can be re-used up to 10 times and retains its catalytic activity in a wide range of organic solvents (up to 90%) making it a promising mimic of peroxidase catalysts. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Plný text