Title data
Achmann, Sabine ; Hermann, Markus ; Hilbrig, Frank ; Jérôme, Valérie ; Hämmerle, Martin ; Freitag, Ruth ; Moos, Ralf:
Direct detection of formaldehyde in air by a Novel NAD⁺- and glutathione-independent formaldehyde dehydrogenase-Based biosensor.
In: Talanta.
Vol. 75
(2008)
Issue 3
.
- pp. 786-791.
ISSN 0039-9140
DOI: https://doi.org/10.1016/j.talanta.2007.12.015
Project information
Project title: |
Project's official title Project's id No information Ha 4424/1-1 |
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Project financing: |
Deutsche Forschungsgemeinschaft |
Abstract in another language
An amperometric enzyme-based sensor-system for the direct detection of formaldehyde in air is under investigation. The biosensor is based on a native bacterial NAD+- and glutathione-independent formaldehyde dehydrogenase as biorecognition element. The enzyme was isolated from Hyphomicrobium zavarzinii strain ZV 580, grown on methylamine hydrochloride in a fed-batch process. The sensor depends on the enzymatic conversion of the analyte to formic acid. Released electrons are detected in an amperometric measurement at 0.2 V vs. Ag/AgCl reference electrode by means of a redox-mediator. To optimize the sensing device, Ca2+ and pyrroloquinoline quinone (PQQ) were added to the buffer solution as reconstitutional substances.
At this stage, the sensor shows linear response in the tested ppm-range with a sensitivity of 0.39 μA/ppm. The signal is highly reproducible with respect to sensitivity and base line signal. Reproducibility of sensitivity is more than 90% within the same bacterial batch and even when enzyme of different bacterial batches is used.