US3598245A
Expired / Lapsed
US
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Separation medium for gel filtration and a method for its preparation
Assignee: Cytiva Sweden AB
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Filing: 1969-10-27
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Granted: 1971-08-10
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Expires: 1989-10-27
Abstract
Abstract A separation medium for gel filtration having an exclusion limit within the molecular weight range of from 10,000 to 10 million consisting of grains of certain water-insoluble copolymers reinforced with a rigid hydrophilic macroporous material, and method for the preparation thereof. The rigid hydrophilic macroporous material can be grains of regenerated cellulose having a bulk density of 2-25 g./dl., and a pore size in the range of from 2 to 2,000 Mu .
Inventors
- 👤 Helmut Determann
- 👤 Theodor Wieland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:45
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/22
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
31 words
A separation medium as claimed in claim 1, wherein the copolymer has an exclusion limit for globular proteins and viruses in the molecular weight range of from 50,000 to 2 million.
Claim 2
Dependent Claim
42 words
A separation medium as claimed in claim 1, wherein the rigid, hydrophilic, macroporous material constitutes pearls of regenerated cellulose having a bulk density of 2-25 g./dl., the cellulose having a pore size in the range of from 2 to 2,000 Mu .
Claim 3
Dependent Claim
102 words
A process of preparing a separation medium in accordance with claim 1, characterized by copolymerizing in the pores of a rigid hydrophilic, macroporous, granular material a hydroxyl-group-containing substance with a bifunctional substance of the formula X-R-Z, wherein X and Z are each halogen or an epoxy group and R is an aliphatic group containing 3-10 carbon atoms in an aqueous solution, the proportions of the hydroxyl-group-containing substance and bifunctional substance being selected so that the resulting copolymer is insoluble in water and obtains an exclusion limit for globular proteins and viruses in the molecular weight range of from 10,000 to 10 million.
Claim 4
Dependent Claim
42 words
A process as claimed in claim 4, wherein the rigid, hydrophilic, macroporous, granular material constitutes pearls of regenerated cellulose of a bulk density of 2-25 g./d1., the grains having a pore size in the range of from 2 to 2,000 Mu .
Claim 5
Dependent Claim
28 words
A process as claimed in claim 4, wherein the content of the hydroxyl-group-containing substance in the aqueous starting solution used in the polymerization process amounts to 2-20 g./dl.
Claim 6
Dependent Claim
28 words
A process as claimed in claim 5, wherein the content of the hydroxyl-group-containing substance in the aqueous starting solution used in the polymerization process amounts to 2-20 g./dl.
Claim 7
Dependent Claim
42 words
A separation medium as claimed in claim 2 wherein the rigid hydrophilic, macroporous material constitutes pearls of regenerated cellulose having a bulk density of 2-25 g./dl., the cellulose having a pore size in the range of from 2 to 2,000 Mu .
Claim 8
Dependent Claim
28 words
The process of claim 4 wherein the copolymer has an exclusion limit for globular proteins and viruses in the molecular weight range of from 50,000 to 2 million.
Claim 9
Dependent Claim
28 words
The process of claim 5 wherein the copolymer has an exclusion limit for globular protein and viruses in the molecular weight range of from 50,000 to 2 million.
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) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |