Patent US4985143A successfully refreshed from Google Patents.
US4985143A
Expired / Lapsed
US
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Method for packing chromatographic beds
Assignee: University of Maryland, College Park
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Filing: 1990-01-31
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Granted: 1991-01-15
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Expires: 2010-01-31
Abstract
Abstract Column chromatography beds are packed through the application of static force. A slurry of the chromatography bed material and a non-viscous liquid is filled into the column plugged at one end, and allowed to settle. The column is transferred to a centrifuge, and centrifuged for a brief period of time to achieve a predetermined packing level, at a range generally of 100-5,000 gravities. Thereafter, the plug is removed, other fixtures may be secured, and the liquid is allowed to flow out through the bed. This results in an evenly packed bed, with no channeling or preferential flow characteristics.
Inventors
- 👤 David H. Freeman
- 👤 Rosalie M. Angeles
- 👤 Suzanne Keller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:14
CPC Classifications
B; B01; B01D; B01D15/00; B01D15/08; B01D15/10; B01D15/20; B01D15/206; G; G01; G01N; G01N30/00; G01N30/02; G01N30/50; G01N30/56; G01N2030/562; G01N2030/565
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
148 words
A process for packing column chromatography beds, consisting essentially of: preparing a slurry of chromatographic bed material and a liquid comprising at least one of water, methanol, chloroform and hexane, the bed material being denser than the liquid, introducing said slurry into a column provided with a removable plug at one end and allowing said slurry to settle in said column such that said bed material falls to said plugged end, thereafter centrifuging said column under the condition that the surface of the liquid is at all points and times above the surface of the bed material, with respect to said plugged end, and continuing said centrifuging for a period of time to obtain a predetermined packing level in said bed material in the substantial absence of channeling, removing said plug from said column and allowing said liquid to drain through the bed and out of the column.
Claim 2
Dependent Claim
148 words
A process for packing column chromatography beds, consisting essentially of: preparing a slurry of chromatographic bed material and a liquid comprising at least one of water, methanol, chloroform and hexane, the bed material being denser than the liquid, introducing said slurry into a column provided with a removable plug at one end and allowing said slurry to settle in said column such that said bed material falls to said plugged end, thereafter centrifuging said column under the condition that the surface of the liquid is at all points and times above the surface of the bed material, with respect to said plugged end, and continuing said centrifuging for a period of time to obtain a predetermined packing level in said bed material in the substantial absence of channeling, removing said plug from said column and allowing said liquid to drain through the bed and out of the column.
Claim 3
Dependent Claim
23 words
The process of claim 1, wherein said centrifuging is conducted at levels which generate a force at least as great as 100 gravities.
Claim 4
Dependent Claim
16 words
The method of claim 2, wherein said level of force achieved through centrifugation is 100-2,000 gravities.
Claim 5
Dependent Claim
26 words
The process of claim 1, wherein said bed material is comprised of material selected from the group consisting of silica gel, alumina powder or mixtures thereof.
Claim 6
Dependent Claim
13 words
The process of claim 1, wherein a plurality of columns are simultaneously treated.
Claim 7
Dependent Claim
15 words
The process of claim 1, wherein said bed material is comprised of a semi-rigid gel.
References Cited (Backward Citations)
US1218416A
Cited
US1663696A
Cited
US1743242A
Cited
US1761228A
Cited
US2071504A
Cited
US3536106A
Cited
US3692669A
Cited
DE2200730A1
Cited
US3935884A
Cited
US4116948A
Cited
US4146063A
Cited
US4142858A
Cited
US4175037A
Cited
US4270921A
Cited
DE2943982A1
Cited
US4422941A
Cited
US4416783A
Cited
US4549584A
Cited
US4483374A
Cited
EP0148360A2
Cited
US4670141A
Cited
SU1214527A1
Cited
US4737292A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-14 | 1994-07-16 | 1995-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-14 | 1998-07-16 | 1999-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-14 | 2002-07-16 | 2003-01-15 | $7700.00 | Window Closed / Lapsed |