US4990291A
Expired / Lapsed
US
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Method of making lipid tubules by a cooling process
Assignee: United States Department of the Navy
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Filing: 1988-02-29
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Granted: 1991-02-05
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Expires: 2008-02-29
Abstract
Abstract Diacetylinic phosophocholines have distinctly different endothermic and exothermic transition temperatures. Lipid tubules are formed by hydrating a diacetylinic phosphocholine at a temperature above its endothermic transition temperature. The hydrated lipid is then cooled slowly to a formation temperature 1° to 10° C. below the exothermic transition temperature to form tubule structures. The tubules structures can be polymerized to form permanent tubules. The tubules can be used in the same manner as a liposome vesicle or they can be metal coated for a variety of applications.
Inventors
- 👤 Paul E. Schoen
- 👤 Paul Yager
- 👤 Joel M. Schnur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:29
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/10; A61K9/127; A61K9/1274
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
78 words
A method of forming tubules relatively free from amorphous material from diacetylinic phosphocholines having hydrocarbon chains of 15 to 29 carbons each comprising the steps of: hydrating a diacetylinic phosphocholine crystalline, lipid powder above its endothermic transition temperature; cooling said hydrated lipid at a rate not exceeding 1° per minute to a formation temperature 1° to 10° C. below the exothermic transition temperature; and holding said formation temperature for 30 minutes to 2 hours to form tubule structures.
Claim 2
Independent Claim
78 words
A method of forming tubules relatively free from amorphous material from diacetylinic phosphocholines having hydrocarbon chains of 15 to 29 carbons each comprising the steps of: hydrating a diacetylinic phosphocholine crystalline, lipid powder above its endothermic transition temperature; cooling said hydrated lipid at a rate not exceeding 1° per minute to a formation temperature 1° to 10° C. below the exothermic transition temperature; and holding said formation temperature for 30 minutes to 2 hours to form tubule structures.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein the hydrated lipid is cooled at a rate of 0.5° C. per 1° C. per minute.
Claim 4
Dependent Claim
20 words
The method of claim 2 wherein the formation temperature is 1° C. to 5° C. below the exothermic transition temperature.
Claim 5
Dependent Claim
16 words
The method according to claim 2 wherein the formation temperature is maintained for about 1 hour.
Claim 6
Dependent Claim
15 words
The method of claim 4 wherein the tubule structure is polymerized to a permanent form.
Claim 7
Dependent Claim
12 words
The method of claim 5 wherein the lipid is 1,2-bis (10,12 heptacosadiynoyl)-sn-glycero-3-phosphocholine.
Claim 8
Dependent Claim
19 words
The method of claim 4 wherein the diacetylinic phosphocholine lipid has at least 27 carbons in each hydrocarbon chain.
Claim 9
Dependent Claim
11 words
The method of claim 7 wherein the lipid is 1,2-bis(11,13 heptacosadiynoyl)-sn-glycero-3-phosphocholine.
Claim 10
Dependent Claim
12 words
The method of claim 7 wherein the lipid is 1,2-bis (9,11 heptacosadiynoyl)-sn-glycero-3-phosphocholine.
Claim 11
Dependent Claim
11 words
The method of claim 7 wherein the lipid 1,2 (8,10 heptacosadiynoyl)-sn-glycero-3-phosphocholine.
Claim 12
Dependent Claim
12 words
The method of claim 7 wherein the lipid is 1,2-bis (7,9 heptacosadiynoyl)-sn-glycero-3-phosphocholine.
Claim 13
Dependent Claim
15 words
The method of claim 7 wherein the tubule structure is polymerized to a permanent form.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |