EP0253548A2
Expired / Lapsed
EP
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Method for the determination of occult blood and chemical compositions therefor
Assignee: Savyon Diagnostics Ltd
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Filing: 1987-07-06
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Granted: —
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Expires: 2007-07-06
Abstract
Abstract A method is disclosed for the determination of pseudo-peroxidases, especially for the determination of occult blood in specimens of human material, which employs stable liquid chemical compositions containing chromogenic materials and a peroxide. Stable liquid chemical compositions for carrying out the method are also described.
Inventors
- 👤 Abraham Ben-Michael
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 08:19
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/72; G01N33/721; G01N33/725
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
148 words
A stable liquid composition for use in determining the presence of occult blood in specimens of human material, comprising (a) a water-miscible aprotic solvent selected from dimethylsulphoxide, dimethylformamide and dimethylacetamide; (b) an aqueous solvent medium; (c) an effective amount of a chelating agent selected from tri-sodium citrate, sodium pyrophosphate, acetanilide, 8-hydroxy-quinoline and the hemi-sulphate salt thereof, and mixtures of any two or more such chelating agents; (d) a stabilizing compound selected from guaiacol sulfonic acid, vanillin, vanillic acid, N-benzylidene- methylamine, N-benzylidenebenzylamine, 10-benzylidene-9-anthrone, 2-(2-hydroxyphenyl)-benzoxazole, 1-hydroxybenzotriazole, 2-hydroxy-benzophenone, 2,4,4 1- trihydroxy-benzophenone, flavianic acid, 2-pyrrolidinone, o-toluamide, p-toluamide, m-toluamide, p-nitrobenzamide, 1-methyl-2-pyrrolidinone, salicylanilide, 2,4,6-collidine, 2-quinoxalinol, 4-methylpyrimidine, benzamide, 4'-nitroacetanilide, ethyl nicotinate, 2-amino-4,6-dimethylpyrimidine, 2-(aminomethyl)pyridine, 4-pyridine carboxylic acid, 2,6- lutidine, 2-amino-6-methylpyridine, and mixtures of any two or more such stabilizing compounds; (e) an organic peroxide, preferably cumene hydroperoxide or hydrogen peroxide or an analogue thereof; and (f) an indicator selected from tetramethylbenzidine and its derivatives and tetramethyl-p-phenylenediamine.
Claim 2
Dependent Claim
148 words
A stable liquid composition for use in determining the presence of occult blood in specimens of human material, comprising (a) a water-miscible aprotic solvent selected from dimethylsulphoxide, dimethylformamide and dimethylacetamide; (b) an aqueous solvent medium; (c) an effective amount of a chelating agent selected from tri-sodium citrate, sodium pyrophosphate, acetanilide, 8-hydroxy-quinoline and the hemi-sulphate salt thereof, and mixtures of any two or more such chelating agents; (d) a stabilizing compound selected from guaiacol sulfonic acid, vanillin, vanillic acid, N-benzylidene- methylamine, N-benzylidenebenzylamine, 10-benzylidene-9-anthrone, 2-(2-hydroxyphenyl)-benzoxazole, 1-hydroxybenzotriazole, 2-hydroxy-benzophenone, 2,4,4 1- trihydroxy-benzophenone, flavianic acid, 2-pyrrolidinone, o-toluamide, p-toluamide, m-toluamide, p-nitrobenzamide, 1-methyl-2-pyrrolidinone, salicylanilide, 2,4,6-collidine, 2-quinoxalinol, 4-methylpyrimidine, benzamide, 4'-nitroacetanilide, ethyl nicotinate, 2-amino-4,6-dimethylpyrimidine, 2-(aminomethyl)pyridine, 4-pyridine carboxylic acid, 2,6- lutidine, 2-amino-6-methylpyridine, and mixtures of any two or more such stabilizing compounds; (e) an organic peroxide, preferably cumene hydroperoxide or hydrogen peroxide or an analogue thereof; and (f) an indicator selected from tetramethylbenzidine and its derivatives and tetramethyl-p-phenylenediamine.
Claim 3
Dependent Claim
20 words
A composition according to claim 1, characterised in that it contains from 100 to 10,000 ppmw of the stabilizing compound.
Claim 4
Dependent Claim
22 words
A composition according to claim 1 or claim 2, characterised in that it contains from 100 to 10,000 ppmw of chelating agent.
Claim 5
Dependent Claim
22 words
A composition according to any one of claims 1 to 3, characterized in that the aqueous solvent medium is a buffer solution.
Claim 6
Dependent Claim
118 words
A composition according to any one of claims 1 to 4, characterized in that it contains, per 1000 ml: (a) from 250 to 350 ml of dimethylsulphoxide or dimethylformamide or dimethyl acetamide; (b) from 650 to 750 ml of distilled water; (c) from 50 to 150 g of citric acid or acetic acid; (d) from 5 to 15 g each of tri-sodium citrate, sodium pyrophosphate and acetanilide, and optionally up to 10 g or 8-hydroxyquinoline hemi-sulphate; (e) from 5 to 15 g of guaiacol sulphonic acid or vanillin; (f) from 0.5 to 2.0 g of tetramethylbenzidine; and (g) from 500 to 1500 p1 of hydrogen peroxide or an analogue thereof, or of cumene hydroperoxide or a derivative thereof.
Claim 7
Dependent Claim
13 words
A composition according to claim 5, having a pH from 3 to 4.
Claim 8
Dependent Claim
128 words
A composition according to any one of claims 1 to 4, characterized in that it contains, per 1000 ml: (a) from 250 to 350 ml of dimethylsulphoxide or dimethylformamide or dimethyl acetamide; (b) from 650 to 750 ml of distilled water; (c) from 50 to 150 g of sodium carbonate; (d) from 5 to 15 g each of tri-sodium citrate, sodium pyrophosphate and acetanilide; (e) from 5 to 15 g of guaiacol sulphonic acid or, optionally, up to 15 g of vanillin or vanillic acid; (f) from 0.5 to 2 g of tetramethyl-p-phenylenediamine alone or in admixture with 4-aminoantipyrine and/or 2,2'-azino-di-(3-ethylbenzothiazoline sulfonic acid) and/or N-1-naphthyl ethylenediamine; and (g) from 500 to 1500 µl of hydrogen peroxide or an analogue thereof, or of cumene hydroperoxide or a derivative thereof.
Claim 9
Dependent Claim
13 words
A composition according to claim 7, having a pH from 10 to 11.
Claim 10
Dependent Claim
36 words
A composition according to claim 7 or claim 8, characterized in that it further contains up to 10 g N-benzylidenemethylamine, N-benzylidenebenzylamine, 10-benzylidene-9-anthrone, 2-(2-hydroxyphenyl)-benzoxazole, 1-hydroxybenzotriazole, 2-hydroxy-benzophenone, 2,4,4'-trihydroxy-benzophenone or a mixture of any two or more such compounds.
Claim 11
Independent Claim
49 words
A method for determining the presence of occult blood in specimens of human material, characterised in that the specimen to be tested is brought into contact with a liquid composition according to any one of claims 1 to 9, and the composition is monitored for the development of colour.
Claim 12
Dependent Claim
17 words
A novel indicator for carrying out chromogenic determinations of occult blood, characterised in that it is tetramethyl-p-phenylenediamine.
Claim 13
Dependent Claim
17 words
A novel indicator for carrying out chromogenic determinations of occult blood, characterised in that it is tetramethyl-p-phenylenediamine.
References Cited (Backward Citations)
No citation records indexed.
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