Patent EP0799896A2 successfully refreshed from Google Patents.
EP0799896A2
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Reagent test strip for determination of blood glucose
Assignee: LifeScan Inc
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Filing: 1997-04-03
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Granted: —
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Expires: 2017-04-03
Abstract
Abstract A reagent test strip is adapted for use in a blood glucose meter. A sample of whole blood is applied to one surface of a matrix on the strip and the meter measures the reflectance of the opposite surface of the matrix at about 635 nm and 700 nm and calculates from the reflectance the concentration of glucose in the sample. The portion of the applied sample that penetrates the matrix and is visible from the testing surface does not absorb to any appreciable extent at 700 nm. Nevertheless, the glucose-containing sample interacts with the components of the reagent-containing matrix to cause a change in reflectance at 700 nm that simulates the effect of the blood color. As a result, the strip can be used in meters that measure glucose concentration in whole blood samples in the presence of optically visible hemoglobin. <IMAGE>
Inventors
- 👤 John L. Smith
- 👤 Yeung S. Yu
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 09:22
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/54; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/66; Y; Y10; Y10S; Y10S435/00; Y10S435/975; Y10T; Y10T436/00; Y10T436/14; Y10T436/142222; Y10T436/143333; Y10T436/144444; Y10T436/25; Y10T436/25375
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
186 words
A reagent test strip for use in an apparatus for determining a concentration of glucose in a sample of whole blood, the apparatus comprising optical means for detecting intensity of light at wavelengths of about 635 nm and about 700 nm reflected from at least a portion of a matrix disposed near one end of the strip, which matrix comprises a) a sample receiving surface for receiving the whole blood sample and passing a portion of it toward a testing surface opposite thereto, b) a structure that selectively retards the passage of red blood cells through the matrix and minimizes the lysing of the cells in the matrix, whereby any portion of the sample that is visible from the testing surface does not absorb light to any appreciable extent at about 700 nm, and c) a reagent for indicating the glucose concentration by creating at the testing surface a change in reflectance at about 700 nm that is substantially equivalent to that produced by the absorbance of hemoglobin in blood and a change in reflectance at about 635 nm that is indicative of the glucose concentration.
Claim 2
Dependent Claim
26 words
The strip of claim 1 in which the matrix comprises a membrane that has pores that trap the red blood cells of the whole blood sample.
Claim 3
Dependent Claim
13 words
The strip of claim 1 in which the matrix comprises an anisotropic membrane.
Claim 4
Dependent Claim
25 words
The strip of claim 3 in which the membrane has pores that are larger near the sample receiving surface and smaller near the testing surface.
Claim 5
Dependent Claim
13 words
The strip of claim 1 in which the matrix comprises a polysulfone membrane.
Claim 6
Dependent Claim
34 words
The strip of claim 1 in which the reagent comprises a dye precursor that forms a chromophore indicative of the glucose concentration, the chromophore absorbing light appreciably at both 635 nm and 700 nm.
Claim 7
Dependent Claim
51 words
The strip of claim 6 in which the dye precursor is selected from: dye couples in the group consisting of 4-aminoantipyrene (AAP) and chromotropic acid; AAP and 8-anilino-1-naphthalenesulfonate (ANS) and combinations thereof; the group consisting of 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) and ANS, MBTH combined with its formaldehyde azine, and combinations thereof.
Claim 8
Dependent Claim
49 words
The strip of claim 1 in which the reagent comprises a first dye precursor that forms a chromophore whose absorbance at 635 nm is indicative of the glucose concentration and a second dye precursor that forms a chromophore whose absorbance at 700 nm simulates the absorbance of whole blood.
Claim 9
Dependent Claim
18 words
The strip of claim 8 in which the first dye precursor comprises MBTH combined with 3-dimethylaminobenzoic acid (DMAB).
Claim 10
Dependent Claim
50 words
The strip of claim 8 in which the second dye precursor is selected from: dye couples in the group consisting of MBTH and primaquine diphosphate (PDP), AAP and PDP, and combinations thereof; or the group consisting of alizarin red S, phenol red, and combinations thereof; and is preferably phenolphthalein complexone.
References Cited (Backward Citations)
No citation records indexed.
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