EP0093595A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Home diagnostic aid and method for determining the presence of occult blood
Assignee: HEMATEC Corp
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Filing: 1983-04-29
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Granted: —
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Expires: 2003-04-29
Abstract
Abstract A one-step, guaiac reagent based, diagnostic aid for determining the presence of occult blood in an aqueous system includes a cellulosic carrier having adsorbed or absorbed thereon guaiac and a promoter, preferably a water-soluble polymer matrix. A dry powdered oxidizing agent, such as a monopersulphate compound, is placed in contact with the carrier. The oxidizing agent is capable of oxidizing guaiac to a blue dye in the presence of water and hemoglobin. The oxidizing agent, in the absence of water, is substantially non-reactive with the guaiac in the carrier. When the diagnostic aid is contacted with water, the oxidizing agent is activated to produce hydrogen peroxide which, in the presence of occult blood, will oxidise the guaiac to a brilliant blue reaction product.
Inventors
- 👤 Henry J. Wells
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 06:18
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/72; G01N33/721; G01N33/725; G01N33/726
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
107 words
A substantially dry, diagnostic aid for use in determining in one step the presence of hemoglobin in an aqueous environment, the diagnostic aid comprising: a composition comprising a cellulosic carrier on which are adsorbed or absorbed guaiac and a medium that promotes the oxidation of guaiac to a blue dye in the presence of water, hemoglobin and an oxidizing agent; and an oxidizing agent in contact with the composition, the oxidizing agent being capable of oxidizing the guaiac to a blue dye in the presence of water and hemoglobin, and the oxidizing agent in the absence of water being substantially non-reactive with the guaiac in the compositure.
Claim 2
Dependent Claim
107 words
A substantially dry, diagnostic aid for use in determining in one step the presence of hemoglobin in an aqueous environment, the diagnostic aid comprising: a composition comprising a cellulosic carrier on which are adsorbed or absorbed guaiac and a medium that promotes the oxidation of guaiac to a blue dye in the presence of water, hemoglobin and an oxidizing agent; and an oxidizing agent in contact with the composition, the oxidizing agent being capable of oxidizing the guaiac to a blue dye in the presence of water and hemoglobin, and the oxidizing agent in the absence of water being substantially non-reactive with the guaiac in the compositure.
Claim 3
Dependent Claim
39 words
A diagnostic aid according to Claim 1, wherein the composition comprises a cellulosic carrier having adsorbed or absorbed thereon guaiac in a polymer matrix, the polymer being soluble in water and preferably being soluble in a solvent for guaiac.
Claim 4
Dependent Claim
40 words
A diagnostic aid according to Claim 1, wherein the composition comprises a cellulosic carrier having guaiac adsorbed or absorbed thereon, the guaiac being adsorbed or absorbed thereon by contacting the carrier with a solution of guaiac in a solvent therefor.
Claim 5
Dependent Claim
20 words
A diagnostic aid according to Claim 1, 2 or 3, wherein the cellulosic carrier comprises a sheet of absorbent material.
Claim 6
Dependent Claim
55 words
A diagnostic aid according to Claim 2, or to Claim 4 when appendant to Claim 2, wherein the polymer is selected from polyethylene glycol, polyvinylpyrollidone, or mixtures thereof, and is preferably a polethylene glycol having a molecular weight ranging from 200 to 20,000 or a polyvinylpyrollidone having a molecular weight ranging from 10,000 to 360,000.
Claim 7
Dependent Claim
52 words
A diagnostic aid according to any preceding claim, wherein the oxidizing agent is selected from a monopersulphate compound, cumene hydroperoxide, tertiary butyl hydroperoxide, or mixtures thereof, the oxidizing agent preferably being a monopersulphate compound, and more preferably being potassium monopersulphate or a mixture of potassium monopersulphate, potassium hydrogen sulphate, and potassium sulphate.
Claim 8
Dependent Claim
98 words
A diagnostic aid according to Claim 2 or 5, or to Claim 4 or 6 when appednant to Claim 2, wherein the polymer and the guaiac are adsorbed or absorbed onto the carrier by dissolving the polymer and guaiac in a mutal solvent therefor, contacting the resulting solution with the carrier, and evaporating substantially all of the solvent, the solvent preferably being selected from a lower aliphatic alcolhol, chloroform, benzene, or mixtures thereof, the lower aliphatic alcohol preferably being an alkanol or alkenol having from one to six carbon atoms, more preferably methanol, isopropanol or a mixture thereof.
Claim 9
Dependent Claim
51 words
A diagnostic aid according to Claim 7, wherein the guaiac is present in the solvent in an amount ranging from 1 to 5% by weight, preferably from 1 to 3% by weight, and wherein the polymer is present in the solvent in an amount ranging from 1 to 60% by volume.
Claim 10
Independent Claim
42 words
A method for determining the presence of hemoglobin in an aqueous environment, the method comprising: placing in contact with the aqueous environment, a diagnostic aid according to any preceding claim; and observing whether a portion of the diagnostic aid is dyed blue.
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