Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1021/ac950692n
Titel (primär) A nitrite sensor based on a highly sensitive nitrite reductase mediator-coupled amperometric detection
Autor Strehlitz, B.; Gründig, B.; Schumacher, W.; Kroneck, P.M.H.; Vorlop, K.-D.; Kotte, H.
Quelle Analytical Chemistry
Erscheinungsjahr 1996
Department UBZ; SAN
Band/Volume 68
Heft 5
Seite von 807
Seite bis 816
Sprache englisch
Abstract Highly sensitive nitrite sensors have been developed for the first time based on mediator-modified electrodes. Tetraheme cytochrome c nitrite reductase from Sulfurospirillum deleyianum and cytochrome cd1 nitrite reductase from Paracoccus denitrificans are able to accept electrons from artificial electron donors, which simultaneously act as electron mediators between the enzyme and an amperometric electrode. In addition to methyl viologen, redox-active compounds such as phenazines (phenosafranin, safranin T, N-methylphenazinium, 1-methoxy-N-methylphenazinium) and triarylmethane redox dyes (bromphenol blue and red) were selected from a range of redox compounds exhibiting the most efficient performance for nitrite detection. After precipitation, the electron mediators were incorporated in a graphite electrode material. Enzyme immobilization is performed by entrapment in a poly(carbamoyl sulfonate) (PCS) hydrogel. Diffusion coefficients and apparent heterogeneous rate constants of the mediators as well as homogeneous rate constants of nitrite sensors were determined by chronoamperometry and cyclic voltammetry. The phenosafranin-modified electrode layered with the PCS hydrogel immobilization of tetraheme cytochrome c nitrite reductase yielded linear current responses up to 250 μM nitrite with a sensitivity of 446.5 mA M-1 cm-2. The detection limit of the enzymatic nitrite sensor was found to be 1 μM nitrite.
dauerhafte UFZ-Verlinkung
Strehlitz, B., Gründig, B., Schumacher, W., Kroneck, P.M.H., Vorlop, K.-D., Kotte, H. (1996):
A nitrite sensor based on a highly sensitive nitrite reductase mediator-coupled amperometric detection
Anal. Chem. 68 (5), 807 - 816 10.1021/ac950692n