EP0042249A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Magnetically-localizable, biodegradable lipid microspheres
Assignee: Northwestern University
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Filing: 1981-06-10
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Granted: —
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Expires: 2001-06-10
Abstract
Abstract A drug carrier formulation consisting of magnetically-localizable, biodegradable lipid microspheres containing a magnetically-responsive substance, one or more diodegradable lipids and one or more nontoxic surfactants is described herein. There is also described a process for preparing such microspheres wherein the magnetically-responsive substance is wetted with surfactant and part of the lipids, then this material is added to the remaining lipids and heated to 90-100°C., water is added, the mixture is sonicated to obtain a microemulsion, which is then cooled and lyophilized to obtain the product.
Inventors
- 👤 Robert Milton Morris
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 07:50
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5094; G; G01; G01N; G01N2446/00; G01N2446/20; G01N2446/80
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
26 words
A magnetically-localizable, biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non- toxic surfactants.
Claim 2
Dependent Claim
26 words
A magnetically-localizable, biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non- toxic surfactants.
Claim 3
Dependent Claim
13 words
Microspheres of claim 1 in which the magnetically-responsive substance is finely divided magnetite.
Claim 4
Dependent Claim
16 words
Microspheres of claim 2 in which the magnetite particles have an average size less than 1000A.
Claim 5
Dependent Claim
30 words
Microspheres of claim 1 in which one of the lipids is a saturated fatty acid having an even number of carbon atoms, and melting in the range of about 30-100°C.
Claim 6
Dependent Claim
25 words
Microspheres of claim 1 in which an admixture of fatty acids are used and the final lipid mixture melts in the range of about 30-100°C.
Claim 7
Dependent Claim
13 words
Microspheres of claim 1 in which one or more non-ionic surfactants is employed.
Claim 8
Dependent Claim
14 words
Microspheres of claim 1 in which the average particle size is less than 4µ.
Claim 9
Dependent Claim
10 words
Microspheres of claim 1 of less than 5µ in diameter.
Claim 10
Dependent Claim
30 words
Microspheres of claim 1 comprising palmitic acid, magnetite particles of average size less than 0 1000A, lecithin and polyoxyethylene sorbitan mono-oleate having an average size of less than about 4u.
Claim 11
Dependent Claim
19 words
A magnetically-localizable, biodegradable drug carrier formulation of claim 1 in which a drug is dispersed in the lipid microspheres.
Claim 12
Dependent Claim
15 words
A drug carrier formulation of claim 10 in which the drug is an oncolytic agent.
Claim 13
Dependent Claim
78 words
A process for preparing a magnetically-localizable, biodegradable drug carrier formulation which is characterized by lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactants, wherein the magnetically-responsive substance is wetted with surfactant and part of the lipids, then this material is added to the remaining lipids and heated to 90-100°C., water is added, the mixture is sonicated to obtain a microemulsion, which is then cooled and lyophilized to obtain the product.
Claim 14
Dependent Claim
78 words
A process for preparing a magnetically-localizable, biodegradable drug carrier formulation which is characterized by lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactants, wherein the magnetically-responsive substance is wetted with surfactant and part of the lipids, then this material is added to the remaining lipids and heated to 90-100°C., water is added, the mixture is sonicated to obtain a microemulsion, which is then cooled and lyophilized to obtain the product.
Claim 15
Dependent Claim
78 words
A process for preparing a magnetically-localizable, biodegradable drug carrier formulation which is characterized by lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactants, wherein the magnetically-responsive substance is wetted with surfactant and part of the lipids, then this material is added to the remaining lipids and heated to 90-100°C., water is added, the mixture is sonicated to obtain a microemulsion, which is then cooled and lyophilized to obtain the product.
Claim 16
Dependent Claim
78 words
A process for preparing a magnetically-localizable, biodegradable drug carrier formulation which is characterized by lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactants, wherein the magnetically-responsive substance is wetted with surfactant and part of the lipids, then this material is added to the remaining lipids and heated to 90-100°C., water is added, the mixture is sonicated to obtain a microemulsion, which is then cooled and lyophilized to obtain the product.
Claim 17
Dependent Claim
15 words
The process of claim 1 characterized in that the magnetically-responsive substance is finely divided magnetite.
Claim 18
Dependent Claim
18 words
The process of claim 2 characterized in that the magnetite particles have an average size less than 1000A.
Claim 19
Dependent Claim
32 words
The process of claim 1 characterized in that one of the lipids is a saturated fatty acid having an even number of carbon atoms, and melting in the range of about 30-100°C.
Claim 20
Dependent Claim
27 words
The process of claim 1 characterized in that an admixture of fatty acids are used and the final lipid mixture melts in the range of about 30-100°C.
Claim 21
Dependent Claim
15 words
The process of claim 1 characterized in that one or more non-ionic surfactants is employed.
Claim 22
Dependent Claim
16 words
The process of claim 1 characterized in that the average particle size is less than 4µ.
Claim 23
Dependent Claim
17 words
The process of claim 1 characterized in that the microspheres are of less than 5u in diameter.
Claim 24
Dependent Claim
36 words
The process of claim 1 characterized in that palmitic acid, magnetite particles of average size 0 less than 1000A, lecithin and polyoxyethylene sorbitan mono-oleate having an average size of less than about 4 p are used.
Claim 25
Dependent Claim
45 words
The process of claim 1 characterized in that a drug is dispersed in the lipid microspheres by adding from 2 to 15% of the drug by weight to the initial lipid mixture to which is added the surfactant and lipid coated magnetite prior to heating.
Claim 26
Dependent Claim
14 words
The process of claim 10 characterized in that the drug is an onocolytic agent.
Claim 27
Dependent Claim
26 words
A magnetically-localizable, biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non- toxic surfactants.
Claim 28
Dependent Claim
26 words
A magnetically-localizable, biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non- toxic surfactants.
Claim 29
Dependent Claim
23 words
A pharmaceutical composition comprising a diluent or carrier and a magnetically-localizable biodegradable drug carrier formulation prepared by a process according to claim 1.
Claim 30
Dependent Claim
42 words
A process for preparing a pharmaceutical composition which comprises mixing a magnetically- locizable biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactantswith a pharmaceutically- acceptable diluent or carrier
Claim 31
Dependent Claim
42 words
A process for preparing a pharmaceutical composition which comprises mixing a magnetically- locizable biodegradable drug carrier formulation which comprises lipid microspheres containing a magnetically-responsive substance, one or more biodegradable lipids and one or more non-toxic surfactantswith a pharmaceutically- acceptable diluent or carrier
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