EQCN-based cholinesterase biosensors
- The binding of acetylcholinesterase (AChE) to a propidium-modified piezoelectric quartz crystal and its surface enzymatic activity have been investigated. Propidium binds to a site remote to the active center of AChE - the peripheral anionic site (PAS) - which is located on the rim of the gorge to the active site. The gold electrodes of the quartz crystal were first modified with 11-mercaptoundecanoic acid to which propidium was coupled. AChE binding was monitored by a quartz crystal nanobalance (QCN), followed by amperometric activity evaluation of the AChE loaded on the sensor. Interestingly, the binding is strong but does not inhibit AChE. However, an excess of propidium in solution inhibits the immobilized enzyme. The surface enzymatic activities observed depend on the amount of enzyme and differ according to the type and species, i.e. number of enzyme subunits (Electrophorus electricus tetrameric, Drosophila melanogaster mono- and dimeric form - DmAChE). The operational stability and regeneration, effect of propidium in solutionThe binding of acetylcholinesterase (AChE) to a propidium-modified piezoelectric quartz crystal and its surface enzymatic activity have been investigated. Propidium binds to a site remote to the active center of AChE - the peripheral anionic site (PAS) - which is located on the rim of the gorge to the active site. The gold electrodes of the quartz crystal were first modified with 11-mercaptoundecanoic acid to which propidium was coupled. AChE binding was monitored by a quartz crystal nanobalance (QCN), followed by amperometric activity evaluation of the AChE loaded on the sensor. Interestingly, the binding is strong but does not inhibit AChE. However, an excess of propidium in solution inhibits the immobilized enzyme. The surface enzymatic activities observed depend on the amount of enzyme and differ according to the type and species, i.e. number of enzyme subunits (Electrophorus electricus tetrameric, Drosophila melanogaster mono- and dimeric form - DmAChE). The operational stability and regeneration, effect of propidium in solution and detection limit for substrate for various AChEs were investigated amperometrically.…
Author details: | Jan Halamek, Carsten Teller, Alexander Makower, Didier Fournier, Frieder W. SchellerORCiDGND |
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URL: | http://www.sciencedirect.com/science/journal/00134686 |
DOI: | https://doi.org/10.1016/j.electacta.2006.03.047 |
ISSN: | 0013-4686 |
Publication type: | Article |
Language: | English |
Year of first publication: | 2006 |
Publication year: | 2006 |
Release date: | 2017/03/24 |
Source: | Electrochimica acta. - ISSN 0013-4686. - 51 (2006), 24, S. 5174 - 5181 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Biochemie und Biologie |
Peer review: | Referiert |