Amperometric nitrate biosensors on the basis of Pseudomonas stutzeri nitrate reductase

Enzymatic Microtiter Plate-Based Nitrate Detection in Environmental and Medical Analysis

“…A cell membrane-localized quinole pool is the natural source for redox equivalents of the P. stutzeri enzyme. In earlier experiments we demonstrated that not only viologens but also phenothiazine or triphenyl methane dyes are effective electron donors for the immobilized enzyme in an am- perometric nitrate sensor (32). Toxic methyl viologen is the prevailing redox mediator reported for other bacterial nitrate reductases (23)(24)(25)(26).…”

Powering denitrification: the perspectives of electrocatalytic nitrate reduction

“…However, kinetic and mechanistic factors come heavily into play when NO 3 − is reduced electrochemically 30 , giving rise to three recurrent fundamental 105 issues • High overpotential related to sluggish reaction kinetics.…”

A New Polyphenol Oxidase Biosensor Mediated by Azure B in Laponite Clay Matrix

“…Moreover, phenothiazines have been used as electron transfer shuttle for biosensors based on reductase enzymes like horseradish peroxidase, nitrate and nitrite reductases [36 ± 40]. For instance, Azure A and B appear to be better mediators than methylviologen, for nitrate and nitrite biosensor applications [39,40]. In order to improve the PPO/laponite biosensor characteristics, we have, therefore, chosen to use Azure B as a redox mediator in the o-quinone detection process.…”