Colorimetric enzymic analysis
AssigneeCranfield Biotechnology Ltd.
InventorsTimothy D. Gibson, John R. Woodward, Irving J. Higgins, William J. Aston, David A. Griffiths
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Abstract
A colorimetric enzymic analytical test element comprises a support and a plurality of reaction zones incorporating a dried enzyme composition, dyestuff and reagent adapted to provide a substantial dosage independent colorimetric display when the concentration of an analyte applied to the elements exceeds a predetermined value.
Claims10
Colorimetric analytical apparatus comprising a test element including a support, the support carrying a zone including a dried enzyme composition, a predetermined amount of a thiol mediator and a dyestuff, the enzyme composition being arranged to produce hydrogen peroxide upon contact of the zone with an analyte, the dyestuff providing a colorimetric display upon reaction with hydrogen peroxide, said colorimetric display being produced by a reversible covalent condensation reaction in the presence of the mediator, the mediator being adapted until exhausted to scavenge hydrogen peroxide and prevent said colorimetric displays said mediator being selected from the group consisting of sodium mercaptoethane sulphonate and sodium mercaptopropane sulphonate, dithioerythrithol, dithiothreitol, mercapto dextran and glutathione.
Dependencies are inferred from the claim text.