Patent EP0336986A1 successfully refreshed from Google Patents.
EP0336986A1
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Polyacrylamide gels
Assignee: Hewlett Packard GmbH Germany
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Filing: 1988-04-09
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Granted: —
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Expires: 2008-04-09
Abstract
Abstract Polyacrylamide gels containing bound dye indicator molecules being sensitive to pH variation are treated with an aqueos solution for a period of time until the shifting of the pK value of the gel, due to the treatment, has finished.
Inventors
- 👤 Martin Wunderling
- 👤 Lothar Rupp
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 17:48
CPC Classifications
G; G01; G01N; G01N33/00; C; C08; C08F; C08F8/00; C08F8/12; C08F2810/00; C08F2810/20
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
66 words
A method for the preparation of polyacrylamide gels containing bound dye indicator molecules being sensitive to pH variation, said method comprising the step of a polymerization of acrylamides and said indicator molecules for forming gels characterized by - treating said gels with an aqueous solution for a period of time until a shifting of the pK value of the gels, due to the treatment, has finished.
Claim 2
Independent Claim
66 words
A method for the preparation of polyacrylamide gels containing bound dye indicator molecules being sensitive to pH variation, said method comprising the step of a polymerization of acrylamides and said indicator molecules for forming gels characterized by - treating said gels with an aqueous solution for a period of time until a shifting of the pK value of the gels, due to the treatment, has finished.
Claim 3
Dependent Claim
23 words
Method according to claim 1, characterized in that said aqueous solution has a pH value in the range of pH 5 to 12.
Claim 4
Dependent Claim
17 words
Method according to claim 1 or 2, characterized in that said aqueous solution is a buffered solution.
Claim 5
Dependent Claim
21 words
Method according to at least one of the preceding claims, characterized in that said solution further comprises an a-amino carboxylic acid.
Claim 6
Dependent Claim
20 words
Method according to claim 4, characterized in that said a-amino carboxylic acid is histidine, preferably L-histidine and/or lysine, preferably L-lysine.
Claim 7
Dependent Claim
27 words
Method according to at least one of the preceding claims, characterized in that said treatment occurs with temperatures in the range of about 20 to 55 C.
Claim 8
Dependent Claim
26 words
Method according to at least one of the preceding claims, characterized in that said dye indicator is a triphenylmethane dye containing at least one hydroxyl group.
Claim 9
Dependent Claim
22 words
Method according to claim 7, characterized in that said triphenylemthane dye is optionally substituted by at least one halogen and/or sulfonic group.
Claim 10
Dependent Claim
30 words
Method according to claim 7 or 8, characterized in that said triphenylmethane dye is selected from the group consisting of phenol red, chlorphenol red, cresol red, cresol sulfonic red, phenolphthalein.
Claim 11
Dependent Claim
53 words
A polyacrylamide gel containing bound dye indicator molecules being sensitive to pH variation, said indicator molecules were bound by a polymerization of an acrylamide and said indicator molecules, characterized in that this particular amido groups of the polyacrylamide gel being hydrolizable by an aqueous solution having a preselected pH value are hydrolized completely.
Claim 12
Dependent Claim
53 words
A polyacrylamide gel containing bound dye indicator molecules being sensitive to pH variation, said indicator molecules were bound by a polymerization of an acrylamide and said indicator molecules, characterized in that this particular amido groups of the polyacrylamide gel being hydrolizable by an aqueous solution having a preselected pH value are hydrolized completely.
Claim 13
Dependent Claim
57 words
Polyacrylamide gel according to claim 10, characterized in that said dye indicator is a triphenylmethane dye having at least one hydroxyl group, said dye indicator molecules being bound via the ortho- position of the hydroxyphenyl ring to the acrylamide polymer chain, said particular hydrolizable amido groups are positioned adjacent to the hydroxyl group of said indicator molecules.
Claim 14
Dependent Claim
33 words
Polyacrylamide gel according to claim 10 or 11, characterized in that a-amino carboxylic acids are bound to the polymer chain by treating said gel with an aqueous solution containing said a-amino carboxylic acids.
Claim 15
Dependent Claim
21 words
Polyacrylamide gel according to claim 12, characterized in that said a-amino carboxylic acids are histidine, preferably L-histidine and/or lysine, preferably L-lysine.
References Cited (Backward Citations)
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