EP0473241A2
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EP
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Method of operation of reflectance-reading devices
Assignee: LifeScan Inc
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Filing: 1987-08-07
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Granted: —
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Expires: 2007-08-07
Abstract
Abstract A method for operating a reflectance-reading device involves triggering a timing circuit by an initial decrease in reflectance by the wetting of the surface whose reflectance is being measured by a fluid which passes through the inert matrix. The method is particularly suitable for the measurement of glucose levels in blood without requiring separation of red blood cells from serum or plasma.
Inventors
- 👤 Roger Phillips
- 👤 Geoffrey Mcgarraugh
- 👤 Frank Jurik
- 👤 Ray Underwood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 12:20
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/8483; G01N33/00; C; C12; C12Q; C12Q1/00; C12Q1/54; G01N33/48; G01N33/50; G01N33/52; G01N33/521; G01N33/523; G01N33/66; G01N21/17; G01N21/47; G01N21/4738; G01N21/474; G01N2021/4752; G01N2021/4757; G01N21/25; G01N21/31; G01N21/314; G01N35/00; G01N35/10; G01N35/1009; G01N35/1016; Y; Y02; Y02A; Y02A90/00; Y02A90/10; Y10; Y10S; Y10S435/00; Y10S435/805; Y10S435/808; Y10S435/81; Y10T; Y10T436/00; Y10T436/11; Y10T436/112499; Y10T436/14; Y10T436/142222; Y10T436/143333; Y10T436/144444
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
107 words
A method of initiating timing of a measurement in a reflectance-reading device, which comprises: taking at least one first reflectance reading from a first surface of a porous matrix prior to application of a sample to a second surface of the matrix; taking at least one additional reflectance reading from the first surface; comparing the additional reflectance reading to the first reflectance reading and initiating time measurement upon a predetermined drop in reflectance resulting from the sample reaching the first surface; and taking at least one measurement reflectance reading at a predetermined time after the additional reflectance reading differs from said reflectance value by the predetermined difference.
Claim 2
Independent Claim
107 words
A method of initiating timing of a measurement in a reflectance-reading device, which comprises: taking at least one first reflectance reading from a first surface of a porous matrix prior to application of a sample to a second surface of the matrix; taking at least one additional reflectance reading from the first surface; comparing the additional reflectance reading to the first reflectance reading and initiating time measurement upon a predetermined drop in reflectance resulting from the sample reaching the first surface; and taking at least one measurement reflectance reading at a predetermined time after the additional reflectance reading differs from said reflectance value by the predetermined difference.
Claim 3
Dependent Claim
36 words
A method according to claim 1, wherein said surface is initially dry and said additional reflectance reading differs from said first reflectance value when a liquid assay medium penetrates to said first surface of said matrix.
Claim 4
Dependent Claim
17 words
A method according to claim 2, wherein said matrix has a dye precursor bound to the matrix.
References Cited (Backward Citations)
No citation records indexed.
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