Patent US3283434A successfully refreshed from Google Patents.
EP0125867A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Assay systems using enzymes requiring NAD(P) as cofactor
Assignee: Medisense Inc
•
Filing: 1984-05-08
•
Granted: —
•
Expires: 2004-05-08
Abstract
Abstract This specification discloses methods of detection or measurement of an enzyme or of its specific substrate, and sensors used in such methods. The present invention is con- cenred with a multi-enzyme system, and the specification discloses, as one aspect of the invention a method of assay in which an electrode poised at a suitable potential is contacted with a system comprising a first enzyme, a cofactor linked with said enzyme and a mediator compound which transfers charge to the electrode from the first enzyme when its electrical state is changed by reaction of cofactor material. The cofactor may be NAD, NADP (both collectively referred to herein as NAD (P) CAMP ATP GTP TTP CTP. The specification particularly illustrates a method of assay in which an electrode (1) poised at a suitable potential is contact with a system comprising a first enzyme El a nicotinamide adenine dinucleotide compound N linked with said enzyme EI and a mediator compound F which transfers charge to the electrode from the first enzyme when its electrical state is changed by a NAD(P) NAD(P)H reaction. The NAD compound may act as a "bridge" between the said enryme// mediator system and further NAD utilizing enzymes E2.
Inventors
- 👤 Graham Davis
- 👤 Hugh Allen Oliver Hill
- 👤 Anthony Edward George Cass
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 17:04
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/1468; A61B5/1486; A61B5/68; A61B5/6846; A61B5/6847; A61B5/6848; C; C12; C12Q; C12Q1/00; C12Q1/001; C12Q1/004; Y; Y10; Y10S; Y10S435/00; Y10S435/817
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
56 words
A method of assay in which an electrode poised at a suitable potential is contacted with a system comprising a first enzyme, a nicotinamide adenine dinucleotide compound linked with said enzyme and a mediator compound which transfers charge to the electrode from the first enzyme when its electrical state is changed by a NAD(P) NAD(P)H reaction.
Claim 2
Independent Claim
56 words
A method of assay in which an electrode poised at a suitable potential is contacted with a system comprising a first enzyme, a nicotinamide adenine dinucleotide compound linked with said enzyme and a mediator compound which transfers charge to the electrode from the first enzyme when its electrical state is changed by a NAD(P) NAD(P)H reaction.
Claim 3
Dependent Claim
84 words
A method as claimed in claim 1 in which a second enzyme is also linked with the N A D(P) compound and a substrate for said second enzyme is present in the said system so that the substrate/second enzyme reaction causes the NAD(P) compound to undergo its reversible reaction and thus affect the first enzyme and transfer charge to the electrode in an amount correlated with the extent of second enzyme/substrate reaction so as to permit assay of either if the other is known.
Claim 4
Dependent Claim
28 words
A method as claimed in claim 2 in which a metal electrode is dipped into a solution containing the mediator, both enzymes, the NAD(P) compound and the substrate.
Claim 5
Dependent Claim
36 words
A method as claimed in claim 2 in which an electrode is coated with mediator, both enzymes and the NAD(P) compound and is dipped into solution containing the substrate to detect substrate or- measure its concentration.
Claim 6
Dependent Claim
40 words
A method as claimed in claim 2 in which an electrode coated with mediator, the first enzyme, the NAD(P) compound, and the substrate is dipped into a solution containing the second enzyme to detect the enzyme or measure its concentration.
Claim 7
Dependent Claim
49 words
A method as claimed in claim 2 in which the first enzyme is glutathione oxido-reductase, the NAD(P) compound is nicotinamide adenine dinucleotide phosphate, the second enzyme is D-iso-citrate dehydrogenase and the substrate is D-iso-citrate, whereby the extent of the catatylic conversion of the substrate to - ketoglutarate is measured.
Claim 8
Dependent Claim
48 words
A method as claimed in claim 2 in which the first enzyme is diaphorase (dihydrolipoamide dehydrogenase), the NAD(P) compound is nicotinamide adenine dinucleotide, the second enzyme is a glycerol dehydrogenase, and the substrate is glycerol, whereby the extent of the catalytic conversion of glycerol to dihydroxyacetone is measured.
Claim 9
Dependent Claim
39 words
A method as claimed in claim 7 in which glycerol ester hydrolase is present together with a triglyceride material so as to yield on enzyme catalysed reaction fatty acids and glycerol as a substrate for the said secxond enzyme.
Claim 10
Dependent Claim
23 words
A method as claimed in claim 1, 2, 3, 4, 5, 6, 7 or 8 in which the mediator compound is a ferrocene.
Claim 11
Dependent Claim
28 words
A method as claimed in claim 1, 2, 3, 4, 5, 6, 7 or 8 in which the mediator is coated on the electrode and is 1,1 -dimethylferrocene.
Claim 12
Dependent Claim
27 words
A method as claimed in claim 1, 2, 3, 4, 5, 6, 7 or 8 in which the mediator is present in solution as a carboxy-substituted ferrocene.
Claim 13
Dependent Claim
15 words
A sensor electrode coated with a ferrocene mediator, glutathione reductase and nicotinamide adenine dinucleotide phosphate.
Claim 14
Dependent Claim
15 words
A sensor electrode coated with a ferrocene mediator, glutathione reductase and nicotinamide adenine dinucleotide phosphate.
Claim 15
Dependent Claim
13 words
A sensor electrode coated with a ferrocene mediator, diaphorase, and nicotinamide adenine dinucleotide.
Claim 16
Dependent Claim
13 words
A sensor electrode coated with a ferrocene mediator, diaphorase, and nicotinamide adenine dinucleotide.
Claim 17
Dependent Claim
17 words
A sensor electrode as claimed in claim 12 or 13 in which the ferrocene is 1,1 -dimethylferrocene.
Claim 18
Dependent Claim
20 words
A sensor electrode as claimed in claim 12 or 13 in which the ferrocene and enzyme are chemically linked together.
Claim 19
Independent Claim
53 words
A method of assay in which an electrode poised at a suitable potential is contacted with a system comprising a first enzyme, a cofactor linked with said enzyme and a mediator compound which transfers charge to the electrode from the first enzyme when its electrical state is changed by reaction of cofactor material.
Claim 20
Independent Claim
53 words
A method of assay in which an electrode poised at a suitable potential is contacted with a system comprising a first enzyme, a cofactor linked with said enzyme and a mediator compound which transfers charge to the electrode from the first enzyme when its electrical state is changed by reaction of cofactor material.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.