US3948743A
Expired / Lapsed
US
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Method for gel electrophoresis
Assignee: Bio Rad Laboratories Inc
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Filing: 1975-04-14
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Granted: 1976-04-06
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Expires: 1995-04-14
Abstract
Abstract Gels for electrophoresis such as polyacrylamide gels are formed in a neutral pH medium containing a salt solution of preselected concentration. This salt is incorporated in the gel and in subsequent use in electrophoresis is displaced upon application of an electrical potential (direct current) by ionic species which form a pH buffer in the gel. Prior to introduction of the buffer, the gel containing the neutral salt is storage stable for prolonged periods of time. The gel is reproducible since it is always formed under the same conditions and the buffer only thereafter introduced.
Inventors
- 👤 James F. Monthony
- 👤 Christopher J. Siebert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:20
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/0052; B01J13/0065; G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/447; G01N27/44704; G01N27/44747
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
37 words
A pre-cast crosslinked polyacrylamide adapted for use in gel electrophoresis and containing therein a strongly ionizable neutral salt in a concentration of about 0.005N - 1.0N the pH of said polyacrylamide being between about 6 and 8.
Claim 2
Dependent Claim
37 words
A pre-cast crosslinked polyacrylamide adapted for use in gel electrophoresis and containing therein a strongly ionizable neutral salt in a concentration of about 0.005N - 1.0N the pH of said polyacrylamide being between about 6 and 8.
Claim 3
Dependent Claim
23 words
A pre-cast crosslinked polyacrylamide in accordance with claim 1 wherein said neutral salt is present in a concentration of about 0.01N - 0.8N.
Claim 4
Dependent Claim
16 words
A pre-cast crosslinked polyacrylamide in accordance with claim 1 wherein said neutral salt is ammonium sulfate.
Claim 5
Dependent Claim
17 words
A pre-cast crosslinked polyacrylamide in accordance with claim 1 wherein the acrylamide crosslinking agent is methylene bis-acrylamide.
Claim 6
Dependent Claim
38 words
A pre-cast crosslinked polyacrylamide in accordance with claim 1 wherein the total concentration of monomer in the solution forming said polyacrylamide is about 2-20% and the proportion of crosslinking agent relative to total monomer content is about 1-10%.
Claim 7
Dependent Claim
18 words
A pre-cast crosslinked polyacrylamide in accordance with claim 1 wherein the pH in said polyacrylamide is about 7.
Claim 8
Dependent Claim
46 words
An improved method for gel electrophoresis comprising: providing a gel suitable for electrophoresis and containing a strong neutral salt at a pH of about 6-8, electrophoretically exchanging a buffer for said strong salt, and applying a sample for resolution into its components to said buffer-containing gel.
Claim 9
Dependent Claim
46 words
An improved method for gel electrophoresis comprising: providing a gel suitable for electrophoresis and containing a strong neutral salt at a pH of about 6-8, electrophoretically exchanging a buffer for said strong salt, and applying a sample for resolution into its components to said buffer-containing gel.
Claim 10
Dependent Claim
28 words
The improved method in accordance with claim 7 and including applying a tracking dye to said gel to indicate the completion of exchange of buffer for said salt.
Claim 11
Dependent Claim
48 words
The improved method in accordance with claim 7 wherein said buffer contains at least one cation having a titratable pK a of 2-10 and at least one anion having a titratable pK a of 2-10, wherein the difference between said pK a 's is not more than 5.
Claim 12
Dependent Claim
21 words
The improved method in accordance with claim 9 wherein the difference between said pK a 's is not more than 3.
Claim 13
Dependent Claim
15 words
The improved method in accordance with claim 9 wherein said buffer also contains strong ions.
Claim 14
Dependent Claim
39 words
The improved method in accordance with claim 7 wherein the concentration of said strong neutral salt and the components of said buffer are initially selected to provide an effective conductivity in said buffer-containing gel of about 200-20,000 micro mhos.
Claim 15
Dependent Claim
35 words
The improved method in accordance with claim 7 wherein said gel is provided by polymerizing acrylamide and a crosslinking agent in an aqueous media containing said strong neutral salt at a pH of about 6-8.
Claim 16
Dependent Claim
72 words
In the method for resolving components of a sample by gel electrophoresis in a polyacrylamide gel containing a buffer, the improvement comprising preforming said gel in the absence of a buffer and in the presence of a strong neutral salt to incorporate the salt in the gel, and thereafter electrophoretically introducing a buffer into said gel in exchange for said neutral salt prior to the application of the sample to said gel.
Claim 17
Dependent Claim
72 words
In the method for resolving components of a sample by gel electrophoresis in a polyacrylamide gel containing a buffer, the improvement comprising preforming said gel in the absence of a buffer and in the presence of a strong neutral salt to incorporate the salt in the gel, and thereafter electrophoretically introducing a buffer into said gel in exchange for said neutral salt prior to the application of the sample to said gel.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |