Noncovalent attachment of NAD+ cofactor onto carbon nanotubes for preparation of integrated dehydrogenase-based electrochemical biosensors
This study describes a facile approach to the preparation of integrated dehydrogenase-based electrochemical biosensors through noncovalent attachment of an oxidized form of beta-nicotinamide adenine dinucleotide (NAD(+)) onto carbon nanotubes with the interaction between the adenine subunit in NAD(+...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 26(2010), 8 vom: 20. Apr., Seite 6028-32 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2010
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Nanotubes, Carbon NAD 0U46U6E8UK Glucose 1-Dehydrogenase EC 1.1.1.47 |
Zusammenfassung: | This study describes a facile approach to the preparation of integrated dehydrogenase-based electrochemical biosensors through noncovalent attachment of an oxidized form of beta-nicotinamide adenine dinucleotide (NAD(+)) onto carbon nanotubes with the interaction between the adenine subunit in NAD(+) molecules and multiwalled carbon nanotubes (MWCNTs). X-ray photoelectron spectroscopic and cyclic voltammetric results suggest that NAD(+) is noncovalently attached onto MWCNTs to form an NAD(+)/MWCNT composite that acts as the electronic transducer for the integrated dehydrogenase-based electrochemical biosensors. With glucose dehydrogenase (GDH) as a model dehydrogenase-based recognition unit, electrochemical studies reveal that glucose is readily oxidized at the GDH/NAD(+)/MWCNT-modified electrode without addition of NAD(+) in the phosphate buffer. The potential for the oxidation of glucose at the GDH/NAD(+)/MWCNT-modified electrode remains very close to that for NADH oxidation at the MWCNT-modified electrode, but it is more negative than those for the oxidation of glucose at the MWCNT-modified electrode and for NADH oxidation at a bare glassy carbon electrode. These results demonstrate that NAD(+) molecules stably attached onto MWCNTs efficiently act as the cofactor for the dehydrogenases. MWCNTs employed here not only serve as the electronic transducer and the support to confine NAD(+) cofactor onto the electrode surface, but also act as the electrocatalyst for NADH oxidation in the dehydrogenase-based electrochemical biosensors. At the GDH/NAD(+)/MWCNT-based glucose biosensor, the current is linear with the concentration of glucose being within a concentration range from 10 to 300 microM with a limit of detection down to 4.81 microM (S/N = 3). This study offers a facile and versatile approach to the development of integrated dehydrogenase-based electrochemical devices, such as electrochemical biosensors and biofuel cells |
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Beschreibung: | Date Completed 01.07.2010 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/la903799n |