caa a22 4500 605507872 CHVBK 20210128100634.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s00775-014-1171-0 doi (NATIONALLICENCE)springer-10.1007/s00775-014-1171-0 A sensitive and stable amperometric nitrate biosensor employing Arabidopsis thaliana nitrate reductase [Elektronische Daten] [Palraj Kalimuthu, Katrin Fischer-Schrader, Günter Schwarz, Paul Bernhardt] Nitrate reductase (NR) from the plant Arabidopsis thaliana has been employed in the development of an amperometric nitrate biosensor that functions at physiological pH. The anion anthraquinone-2-sulfonate (AQ) is used as an effective artificial electron transfer partner for NR at a glassy carbon (GC) electrode. Nitrate is enzymatically reduced to nitrite and the oxidized form of NR is electrochemically reduced by the hydroquinone form of the mediator (AQH2). The GC/NR electrode shows a pronounced cathodic wave for nitrate reduction and the catalytic current increases linearly in the nitrate concentration range of 10-400µM with a correlation coefficient of 0.989. Using an amperometric method, a low detection limit of 0.76nM (S/N=3) was achieved. The practical application of the present electrochemical biosensor was demonstrated by the determination of nitrate concentration in natural water samples and the results agreed well with a standard spectroscopic method. Graphical Abstract: SBIC, 2014 Nitrate reductase nationallicence Voltammetry nationallicence Molybdenum nationallicence Kalimuthu Palraj School of Chemistry and Molecular Biosciences, University of Queensland, 4072, Brisbane, Australia aut Fischer-Schrader Katrin Department of Chemistry and Center for Molecular Medicine, Institute of Biochemistry, Cologne University, Zülicher Str. 47, 50674, Cologne, Germany aut Schwarz Günter Department of Chemistry and Center for Molecular Medicine, Institute of Biochemistry, Cologne University, Zülicher Str. 47, 50674, Cologne, Germany aut Bernhardt Paul School of Chemistry and Molecular Biosciences, University of Queensland, 4072, Brisbane, Australia aut JBIC Journal of Biological Inorganic Chemistry Springer Berlin Heidelberg 20/2(2015-03-01), 385-393 0949-8257 20:2<385 2015 20 775 https://doi.org/10.1007/s00775-014-1171-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00775-014-1171-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kalimuthu Palraj School of Chemistry and Molecular Biosciences, University of Queensland, 4072, Brisbane, Australia aut NATIONALLICENCE 700 1- Fischer-Schrader Katrin Department of Chemistry and Center for Molecular Medicine, Institute of Biochemistry, Cologne University, Zülicher Str. 47, 50674, Cologne, Germany aut NATIONALLICENCE 700 1- Schwarz Günter Department of Chemistry and Center for Molecular Medicine, Institute of Biochemistry, Cologne University, Zülicher Str. 47, 50674, Cologne, Germany aut NATIONALLICENCE 700 1- Bernhardt Paul School of Chemistry and Molecular Biosciences, University of Queensland, 4072, Brisbane, Australia aut NATIONALLICENCE 773 0- JBIC Journal of Biological Inorganic Chemistry Springer Berlin Heidelberg 20/2(2015-03-01), 385-393 0949-8257 20:2<385 2015 20 775