Methods for encapsulating plasmids in lipid bilayers
AssigneeInex Pharmaceuticals Corporation
InventorsJeffery J. Wheeler, Michael Hope, Pieter R. Cullis, Marcel B. Bally
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Abstract
Plasmid-lipid particles which are useful for transfection of cells in vitro or in vivo are described. The particles can be formed using either detergent dialysis methods or methods which utilize organic solvents. The particles are typically 65-85 nm, fully encapsulate the plasmid and are serum-stable.
Claims29
A method for the preparation of serum-stable plasmid-lipid particles, comprising:
- (a) combining a plasmid with cationic lipids in a detergent solution to provide a coated plasmid-lipid complex;
- (b) contacting non-cationic lipids with said coated plasmid-lipid complex to provide a solution comprising detergent, a plasmid-lipid complex and non-cationic lipids;
- and
- (c) removing said detergent from said solution of step (b) to provide a solution of serum-stable plasmid-lipid particles, wherein said plasmid is encapsulated in a lipid bilayer and said particles are resistant to degradation in serum, and wherein the particles have a diameter ranging from about 50 to about 150 nm.
A method for the preparation of serum-stable plasmid-lipid particles, comprising:
- (a) preparing a mixture comprising cationic lipids and non-cationic lipids in an organic solvent;
- (b) contacting an aqueous solution of plasmid with said mixture prepared in step (a) to provide a single phase;
- and
- (c) removing said organic solvent to provide a suspension of plasmid-lipid particles, wherein said plasmid is encapsulated in a lipid layer and said particles are resistant to degradation in serum, and wherein the particles have a diameter ranging from about 50 to about 150 nm.
A method for the preparation of serum-stable plasmid-lipid particles, comprising:
- a) combining a plasmid with cationic lipids in a first detergent solution to provide a coated plasmid-lipid complex;
- b) contacting non-cationic lipids with said coated plasmid-lipid complex to provide a second solution comprising detergent, a plasmid-lipid complex and non-cationic lipids and adding a polyethylene glycol-lipid conjugate to said second solution;
- and
- c) removing said detergent from said second solution to provide a solution of serum-stable plasmid-lipid particles, wherein said plasmid is encapsulated in a lipid bilayer and said particles are resistant to degradation in serum, and wherein the particles have a diameter ranging from about 50 to about 150 nm.
A method for the preparation of serum-stable plasmid-lipid particles, comprising:
- a) preparing a mixture comprising cationic lipids and non-cationic lipids in an organic solvent, wherein said non-cationic lipids comprise a polyethylene glycol-lipid conjugate;
- b) contacting an aqueous solution of plasmid with said mixture prepared in step (a) to provide a single phase;
- and
- c) removing said organic solvent to provide a suspension of plasmid-lipid particles, wherein said plasmid is encapsulated in a lipid bilayer and said particles are resistant to degradation in serum, and wherein the particles have a diameter ranging from about 50 to about 150 nm.
Dependencies are inferred from the claim text.