EP1130111A2
Expired / Lapsed
EP
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Diagnostics based on tetrazolium compounds
Assignee: LifeScan Inc
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Filing: 2001-02-23
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Granted: —
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Expires: 2021-02-23
Abstract
Abstract A reagent is suitable for measuring the concentration of an analyte in a hemoglobin-containing biological fluid, such as whole blood. The reagent comprises a flavin-dependent enzyme that has specificity for the analyte, a flavin cofactor if, and only if, a flavin is not bound to the enzyme, a tetrazolium dye precursor, an electron transfer agent, and a nitrite salt. The reagent causes dye formation that is a measure of the analyte concentration. The nitrite salt suppresses interfering dye formation caused non-enzymatically by the hemoglobin. Preferably, the reagent is used in a dry strip for measuring glucose in whole blood.
Inventors
- 👤 Tianmei Ouyang
- 👤 Yeung Siu Yu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 12:32
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/26; C12Q1/32; C12Q1/54; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N33/525; G01N33/64; Y; Y10; Y10S; Y10S435/00; Y10S435/962; Y10S435/97; Y10T; Y10T436/00; Y10T436/17; Y10T436/173076
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
48 words
A reagent for measuring a concentration of an analyte in a hemoglobin-containing
biological fluid, comprising: a) a flavin-dependent enzyme that has a flavin bound to it and that has
specificity for the analyte, b) a tetrazolium dye precursor, c) an electron transfer agent, and d) a nitrite salt.
Claim 2
Dependent Claim
58 words
A reagent for measuring a concentration of an analyte in a hemoglobin-containing
biological fluid, comprising: a) a flavin-dependent enzyme that has specificity for the analyte and does not
have a flavin bound to it, b) flavin mononucleotide (FMN) or flavin adenine dinucleotide (FAD). c) a tetrazolium dye precursor, d) an electron transfer agent, and e) a nitrite salt.
Claim 3
Dependent Claim
17 words
The reagent of claim 1 in which the analyte is glucose and the enzyme is glucose
oxidase.
Claim 4
Dependent Claim
13 words
The reagent of any preceding claim in which the dye precursor is water-soluble.
Claim 5
Dependent Claim
20 words
The reagent of any preceding claim in which the electron transfer agent comprises
phenazine methosulfate (PMS) or an analog thereof.
Claim 6
Dependent Claim
12 words
The reagent of any preceding claim further comprising a divalent metal stabilizer.
Claim 7
Dependent Claim
36 words
A dry reagent strip for measuring a concentration of an analyte in a hemoglobin-containing
biological fluid comprising a support layer on which is a test pad having a
coating of the reagent of any preceding claim.
Claim 8
Dependent Claim
14 words
The strip of claim 7 in which the test pad has a positively-charged surface.
Claim 9
Dependent Claim
16 words
The strip of claim 7 or claim 8 in which the test pad comprises a polyamide.
Claim 10
Dependent Claim
19 words
The strip of any of claims 7 to 9 further comprising a bibulous top layer overlaying
the test pad.
Claim 11
Dependent Claim
68 words
A dry reagent strip for measuring a concentration of an analyte in a hemoglobin-containing
biological fluid comprising a support layer on which is a test pad and a top
laying overlaying the test pad in which a first part of the reagent of any of claims 1 to 6 is
on the test pad and a second part of the reagent is on the support and/or top layer.
Claim 12
Dependent Claim
12 words
The strip of claim 11 in which the top layer is bibulous.
Claim 13
Dependent Claim
29 words
The strip of claim 11 further comprising a spacer and channel between the top layer
and test pad to provide a capillary path between the top layer and pad.
Claim 14
Dependent Claim
17 words
The strip of claim 11 in which the tetrazolium dye precursor is 2,2'-dibenzothiazolyl-5,5'-bis[4-di(2-sulfoethyl)carbamoylphenyl]-3,3'-(3,3'-dimethoxy-
4,4'-biphenylene)ditetrazolium,
disodium salt (WST-5).
Claim 15
Dependent Claim
73 words
A dry reagent test strip for measuring a concentration of glucose in a hemoglobin-containing
biological fluid, comprising: a) a support layer, b) on the support layer, a test pad having a coating that comprises: i) glucose oxidase that has a flavin bound to it, ii) a tetrazolium dye precursor, and iii) PMS or an analog thereof, and c) on the test pad, a bibulous top layer that is coated with a nitrite salt.
Claim 16
Dependent Claim
80 words
A dry reagent test strip for measuring a concentration of glucose in a hemoglobin-containing
biological fluid, comprising: a) a support layer, b) on the support layer, a test pad having a coating that comprises: i) a flavin-dependent enzyme that does not have a flavin bound to it, ii) FMN or FAD, iii) a tetrazolium dye precursor, and iv) PMS or an analog thereof, and c) on the test pad, a bibulous top layer that is coated with a nitrite salt.
References Cited (Backward Citations)
No citation records indexed.
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