US5096629A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing lipid powder for use in preparing liposomes and method for preparing liposomes
Assignee: Nippon Fine Chemical Co Ltd
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Filing: 1989-08-28
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Granted: 1992-03-17
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Expires: 2009-08-28
Abstract
Abstract The present invention provides (1) a method for preparing lipid powder for use in the preparing liposome, which comprises supplying at a constant speed an organic solvent solution of lipids having liposome membrane forming ability to a tubular heater heated externally, evaporating the organic solvent in the heater to prepare a mixture substantially of solids and organic solvent vapor and introducing this mixture at a high speed into a vacuum chamber of not more than 300 mm Hg, to volatilize the organic solvent instantaneously and dry the solids, and (2) a method for preparing liposomes comprising dispersing the lipid powder obtained by the above method (1) into an aqueous solvent.
Inventors
- 👤 Yukihiro Nanba
- 👤 Toshiya Ueno
- 👤 Toshiyuki Sakakibara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 06:46
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/10; A61K9/127; A61K9/1277; Y; Y10; Y10S; Y10S159/00; Y10S159/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
107 words
A method for preparing liposomes comprising the steps of: i) supplying at a constant speed an organic solvent solution of a mixture of lipids having liposome membrane forming ability to a tubular heater heated externally, ii) evaporating the organic solvent in the heater to prepare a mixture substantially of solids and overheated organic solvent vapor, iii) introducing this mixture at a high speed of over 0.1 times the sound speed into the vacuum chamber of not more than 300 mm Hg to volatilize the organic solvent instantaneously and dry the solids, whereby lipid powder is obtained, and iv) dispersing the resulting lipid powder into an aqueous solvent.
Claim 2
Independent Claim
107 words
A method for preparing liposomes comprising the steps of: i) supplying at a constant speed an organic solvent solution of a mixture of lipids having liposome membrane forming ability to a tubular heater heated externally, ii) evaporating the organic solvent in the heater to prepare a mixture substantially of solids and overheated organic solvent vapor, iii) introducing this mixture at a high speed of over 0.1 times the sound speed into the vacuum chamber of not more than 300 mm Hg to volatilize the organic solvent instantaneously and dry the solids, whereby lipid powder is obtained, and iv) dispersing the resulting lipid powder into an aqueous solvent.
Claim 3
Dependent Claim
24 words
A method according to claim 1 comprising dispersing into an aqueous solvent the resultant lipid power and a desired fat-soluble or amphipathic substance simultaneously.
Claim 4
Dependent Claim
35 words
A method according to claim 1 in which the aqueous solvent is one member selected from the group consisting of water, an aqueous solution of inorganic salts, and an aqueous solution of sugar or water.
Claim 5
Dependent Claim
26 words
A method according to claim 1 in which said lipid mixture is a mixture of lipids selected from the group consisting of phospholipids, glycolipids and cholesterols.
Claim 6
Dependent Claim
80 words
A method according to claim 4 in which said phospholipid is one member selected from the group consisting of lecithin, yolk lecithin, dimyristoylphospharidylcholine, dipalmitoylphosphatidylcholine, distearoylphosphatidylcholine, dioleylphosphatidylcholine, phosphatidyl ethanolamine, phosphatidylglycerol, sphingomyelin and phosphatidylinositol and hydrogenerated lecithin; said glycolipid is one member selected from the group consisting of myristyl glycoside, cholesteryl glycoside, ganglioside GM 1 , ganglioside GM 3 and sulfatide; and said cholesterol is one member selected from the group consisting of cholesterol, cholesterol acetate, dihydrocholesterol, phytosterol, sitosterol, stigmasterol and campesterol.
Claim 7
Dependent Claim
21 words
A method according to claim 4 in which said lipid mixture is a mixture of cholesterol and lipids other than cholesterols.
Claim 8
Dependent Claim
61 words
A method according to claim 6 in which said lipid mixture comprises a mixture of: a) dipalmitoylphosphatidylcholine, dipalmitoylphosphatidylglycerol and cholesterol, b) hydrogenated yolk lecithin and cholesterol, c) hydrogenated soybean lecithin and cholesterol, d) yolk phosphatidylcholine, yolk phosphatidyl glycerol and cholesterol, e) dimyristoylphosphatidylcholine, dimiristoylphosphatidic acid and cholesterol, f) hydrogenated yolk lecithin, hydrogenated yolk phospatidylglycerol and cholesterol, or g) dimyristoylphoshatidylcholine, dimyristoylphosphatidylglycerol and cholesterol.
References Cited (Backward Citations)
US4311712A
Cited
US4229360A
Cited
US4229360B1
Cited
US4508703A
Cited
JPS607933A
Cited
JPS607932A
Cited
JPS6012127A
Cited
US4830858A
Cited
JPS6252724A
Cited
JPS62152531A
Cited
US4950432A
Cited
US4935171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-03-17 | 1995-09-16 | 1996-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-17 | 1999-09-16 | 2000-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-17 | 2003-09-16 | 2004-03-17 | $7700.00 | Window Closed / Lapsed |