Method of coating fine particles with lipid film

• US 7,678,415 B2
• Filed: 10/04/2001
• Issued: 03/16/2010
• Est. Priority Date: 10/04/2000
• Status: Expired due to Fees

• Current Assignee: Kyowa Hakko Kirin Company Limited (Kirin Holdings Company Limited)
• Original Assignee: Kyowa Hakko Kirin Company Limited (Kirin Holdings Company Limited)
• Inventors: Kusano, Hiroko, Yamauchi, Masahiro, Iwata, Takeshi, Akinaga, Shiro, Uochi, Takaaki, Kato, Yasuki
• Primary Examiner(s): LIGHTFOOT, ELENA TSOY
• Application Number:
  US10/398,222
• Publication Number:
  US 20040022938A1
• Time in Patent Office: 3,085 Days
• Field of Search: 427/212, 427/213.3
• US Class Current: 427/213.3
• CPC Class Codes: A61K 31/7088 Compounds having three or more nucleosides or nucleotides
• CPC Class Codes: A61K 47/6911 the form being a liposome
• CPC Class Codes: A61K 9/127 Liposomes
• CPC Class Codes: A61K 9/1271 Non-conventional liposomes, e.g. PEGylated liposomes, liposomes coated with polymers liposome as conjugate A61K47/6911
• CPC Class Codes: A61K 9/1272 with substantial amounts of non-phosphatidyl, i.e. non-acylglycerophosphate, surfactants as bilayer-forming substances, e.g. cationic lipids with cholesterol as the only non-phosphatidyl surfactant A61K9/127; lipids as modifying agent A61K47/543
• CPC Class Codes: A61K 9/141 Intimate drug-carrier mixtures characterised by the carrier, e.g. ordered mixtures, adsorbates, solid solutions, eutectica, co-dried, co-solubilised, co-kneaded, co-milled, co-ground products, co-precipitates, co-evaporates, co-extrudates, co-melts; Drug nanoparticles with adsorbed surface modifiers (co) spray-dried products A61K9/16, (co) lyophilised products A61K9/19; the carrier being chemically bound to the active ingredient A61K47/50
• CPC Class Codes: A61K 9/146 with organic macromolecular compounds
• CPC Class Codes: A61K 9/5015 Organic compounds, e.g. fats, sugars
• CPC Class Codes: A61K 9/5123 Organic compounds, e.g. fats, sugars
• CPC Class Codes: A61K 9/5192 Processes
• CPC Class Codes: B01J 13/12 removing solvent from the wall-forming material solution

Abstract

An object of the present invention is to provide a safe, convenient and efficient method for coating fine particles with lipid membrane.

There is provided a method for coating fine particles with lipid membrane, characterized in that, the rate of a polar organic solvent in an aqueous solution containing the polar organic solvent where the fine particles are dispersed and lipid is dissolved, is decreased.

Claims

1. A method for coating a complex of a nucleic acid and a liposome with closed vesicles of a lipid bilayer, the liposome comprising cationic lipid, the complex obtained by mixing the nucleic acid and the liposome in water, which consists of the steps of (i) and (ii):

(i) suspending the complex in an aqueous solution consisting essentially of;

water,

polar organic solvent(s) selected from an alcohol, a glycol and a polyalkylene glycol, and

lipid(s) selected from phospholipid, glyceroglycolipid, sphingoglycolipid, cholesterol and synthetic lipid, excluding a cationic lipid,

wherein the complex has a diameter of 10 nm to 1,000 nm, and

wherein the lipid(s) is dissolved in the aqueous solution; and

(ii) adding water to the aqueous solution in which the complex is suspended, so as to decrease the vol % concentration of the polar organic solvent(s) in the aqueous solution, whereby the complex is coated with closed vesicles of the lipid bilayer formed of the lipid(s).

5. The method according to claim 1 or 2, wherein the complex contains a water-soluble polymer derivative.

6. The method according to claim 1 or 2, wherein the liposome comprises a phospholipid and a dextran sulfate sodium salt.

7. The method according to claim 1 or 2, wherein the alcohol is ethanol.

8. The method according to claim 1 or 2, wherein the glycol is a propylene glycol.

9. The method according to claim 1 or 2, wherein the polyalkylene glycol is polyethylene glycol.

10. The method according to claim 5, wherein the water-soluble polymer derivative is one or more member(s) selected from polyethylene glycolated lipid, a polyethylene glycol alkyl ether, a polyethylene glycol castor oil derivative, a polyethylene glycol sorbitan fatty acid ester, a polyethylene glycol stearate, a copolymer of ethylene glycol with propylene glycol and a glycerol ester.

11. The method according to claim 1 or 2, wherein the lipid(s) is one or more member(s) selected from phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, lysophosphatidylcholine, sphingomyelin, polyethylene glycolated phospholipid, egg yolk lecithin, soybean lecithin and hydrogenated phospholipid.

12. The method according to claim 1 or 2, wherein the lipid(s) is a mixture of egg yolk phosphatidylcholine (EggPC) and 1,2-distearoyl-sn-glycero-3-phosphatidylethanolamine-N-(polyethyleneglycol 2000)(PEG-DSPE).

13. The method according to claim 1 or 2, wherein the polar organic solvent(s) is ethanol.

2. A method for coating a complex of a nucleic acid and a liposome with closed vesicles of a lipid bilayer, the liposome comprising cationic lipid, the complex obtained by mixing the nucleic acid and the liposome in water, which consists of the steps of (i), (ii), (iii) and (iv):

(i) suspending the complex in liquid A consisting essentially of;

water, and

polar organic solvent(s) selected from an alcohol, a glycol and a polyalkylene glycol,

wherein the complex has a diameter of 10 nm to 1,000 nm,

(ii) dissolving lipid(s) selected from phospholipid, glyceroglycolipid, sphingoglycolipid, cholesterol and synthetic lipid, excluding a cationic lipid, in liquid B consisting essentially of;

polar organic solvent(s) selected from an alcohol, a glycol and a polyalkylene glycol, and optionally water,

(iii) mixing the liquid A and the liquid B, to obtain liquid C in which the complex is suspended, and

(iv) adding water to the liquid C so as to decrease the vol % concentration of the polar organic solvent(s), to obtain liquid D, and whereby the complex is coated with closed vesicles of the lipid bilayer formed of the lipid(s).

3. The method according to claim 2, wherein the concentrations of the polar organic solvent(s) in the liquid A and the liquid B are 60 to 90 vol %.

4. The method according to claim 3, wherein the concentration of the polar organic solvent(s) in the liquid D is 50 vol % or less.