Determination of sulfite in beer samples using an amperometric fill and flow channel biosensor employing sulfite oxidase Gooding, John en_US Hibbert, D. Brynn en_US Zhao, Min en_US 2021-11-25T13:14:52Z 2021-11-25T13:14:52Z 2006 en_US
dc.description.abstract A simple method is described to determine sulfite in beer samples using a fill and flow channel biosensor. A droplet of sample is placed into the inlet of a rectangular flow cell and begins to flow through the channel by capillarity. The flow is maintained and controlled by a porous outlet plug of defined porosity. In a rectangular flow cell, the sample solution flows through three consecutive zones: over a predictor electrode, an enzyme layer and a detector electrode. Together these three zones enable the differentiation between current due to sulfite and current due to other electroactive species in the sample. The predictor electrode is located upstream, and on the opposite channel wall to the enzyme layer and detector electrode, and is poised at the same potential (+0.65 V versus Ag/AgCl) as the detector electrode. On this electrode, the current contribution from all species in the sample solution that are oxidized at that potential is determined. The enzyme layer contains sulfite oxidase, which, in the process of oxidizing sulfite, produces hydrogen peroxide, which itself is reduced by excess sulfite. The current at the downstream detector electrode is therefore different from that at the predictor electrode as a result of the enzyme reaction and the difference of the currents, corrected for the dimensions of the electrodes, is proportional to the concentration of sulfite. The method enables a straightforward correction of the interfering current at the detector electrode and a determination of the analyte concentration. The effect of interferences from ascorbic acid, ethanol, sorbic acid and tartaric acid in the detection of sulfite is efficiently removed. The concentration of sulfite in a sample of beer measured by the biosensor is equivalent to that measured using a reference method based on the AOAC-recommended Monier-Williams method. © 2005 Elsevier B.V. All rights reserved. en_US
dc.identifier.issn 0003-2670 en_US
dc.language English
dc.language.iso EN en_US
dc.rights CC BY-NC-ND 3.0 en_US
dc.rights.uri en_US
dc.source Legacy MARC en_US
dc.subject.other Biosensors en_US
dc.subject.other Capillarity en_US
dc.subject.other Electrodes en_US
dc.subject.other Enzyme kinetics en_US
dc.subject.other Hydrogen peroxide en_US
dc.title Determination of sulfite in beer samples using an amperometric fill and flow channel biosensor employing sulfite oxidase en_US
dc.type Journal Article en
dcterms.accessRights open access
dspace.entity.type Publication en_US
unsw.description.publisherStatement Journal homepage: en_US
unsw.identifier.doiPublisher en_US
unsw.relation.faculty Science
unsw.relation.ispartofissue 1 en_US
unsw.relation.ispartofjournal Analytica Chimica ACTA en_US
unsw.relation.ispartofpagefrompageto 195-200 en_US
unsw.relation.ispartofvolume 556 en_US
unsw.relation.originalPublicationAffiliation Gooding, John, Chemistry, Faculty of Science, UNSW en_US
unsw.relation.originalPublicationAffiliation Hibbert, D. Brynn, Chemistry, Faculty of Science, UNSW en_US
unsw.relation.originalPublicationAffiliation Zhao, Min, Chemistry, Faculty of Science, UNSW en_US School of Chemistry *
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Determination of Sulfite in Beer for UNSWworks.doc.pdf
99.53 KB
Resource type