US4384975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparation of microspheres
Assignee: SADOZ Inc
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Filing: 1980-06-13
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Granted: 1983-05-24
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Expires: 2000-06-13
Abstract
Abstract Microspheres, prepared by solvent removal from an oil-in-water emulsion using carboxylic acid salt surfactant, e.g., sodium oleate as the emulsifier.
Inventors
- 👤 Jones W. Fong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:59
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/16; A61K9/1682; A61K9/1694; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/12; B01J13/125
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
73 words
A process for the preparation of microspheres having a particulate core material encapsulated by a polymer coating which comprises, dissolving the polymer in a volatile, water-immiscible solvent in which the core material is not soluble, adding the core material particles, mixing the resulting dispersion with an aqueous solution containing sodium oleate or potassium oleate as an emulsifier to form an oil-in-water emulsion, and removing the solvent to form discrete microcapsules free of agglomerates.
Claim 2
Dependent Claim
73 words
A process for the preparation of microspheres having a particulate core material encapsulated by a polymer coating which comprises, dissolving the polymer in a volatile, water-immiscible solvent in which the core material is not soluble, adding the core material particles, mixing the resulting dispersion with an aqueous solution containing sodium oleate or potassium oleate as an emulsifier to form an oil-in-water emulsion, and removing the solvent to form discrete microcapsules free of agglomerates.
Claim 3
Dependent Claim
13 words
The process according to claim 1 wherein the polymer is a biodegradable polymer.
Claim 4
Dependent Claim
35 words
The process according to claim 2 wherein the biodegradable polymer is polylactic acid, polyglycolic acid, polyhydroxybutyric acid, polycaprolactone, polyalkylene oxalate, or a polyalkylene glycol ester of acids of the citric acid cycle or copolymers thereof.
Claim 5
Dependent Claim
12 words
The process according to claim 3 wherein the polymer is polylactic acid.
Claim 6
Dependent Claim
31 words
The process according to claim 4 wherein the core material is selected from the group consisting of thioridazine, bromocriptine, a mixture of dihydroergocornine, dihydroergocristine, and dihydroergokryptine, and acid addition salts thereof.
Claim 7
Dependent Claim
13 words
The process according to claim 1 wherein the core material is a drug.
Claim 8
Dependent Claim
13 words
The process according to claim 6 wherein the polymer is a biodegradable polymer.
Claim 9
Dependent Claim
28 words
The process according to claim 1 wherein the polymer is selected from the group consisting of cellulosic polymers, polyvinylacetate, natural or synthetic rubbers, polyvinyl chloride, polyacrylates, and polystyrene.
Claim 10
Dependent Claim
63 words
A process for the preparation of microspheres having homogeneous mixture of a polymer and core material which comprises, dissolving the polymer and core material in a volatile, water-immiscible solvent, mixing the polymer-core material-solvent system with an aqueous solution containing sodium oleate or potassium oleate as an emulsifier to form an oil-in-water emulsion, and removing the solvent to form discrete microprills free of agglomerates.
Claim 11
Dependent Claim
63 words
A process for the preparation of microspheres having homogeneous mixture of a polymer and core material which comprises, dissolving the polymer and core material in a volatile, water-immiscible solvent, mixing the polymer-core material-solvent system with an aqueous solution containing sodium oleate or potassium oleate as an emulsifier to form an oil-in-water emulsion, and removing the solvent to form discrete microprills free of agglomerates.
Claim 12
Dependent Claim
13 words
The process, according to claim 9 wherein the polymer is a biodegradable polymer.
Claim 13
Dependent Claim
35 words
The process according to claim 10 wherein the biodegradable polymer is polylactic acid, polyglycolic acid, polyhydroxybutyric acid, polycaprolactone, polyalkylene oxalate, or a polyalkylene glycol ester of acids of the citric acid cycle or copolymers thereof.
Claim 14
Dependent Claim
12 words
The process according to claim 11 wherein the polymer is polylactic acid.
Claim 15
Dependent Claim
31 words
The process according to claim 12 wherein the core material is selected from the group consisting of thioridazine, bromocriptine, a mixture of dihydroergocornine, dihydroergocristine, and dihydroergokryptine, and acid addition salts thereof.
Claim 16
Dependent Claim
13 words
The process according to claim 9 wherein the core material is a drug.
Claim 17
Dependent Claim
13 words
The process according to claim 14 wherein the polymer is a biodegradable polymer.
Claim 18
Dependent Claim
28 words
The process according to claim 9 wherein the polymer is selected from the group consisting of cellulosic polymers, polyvinylacetate, natural or synthetic rubbers, polyvinyl chloride, polyacrylates, and polystyrene.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-23 | 1986-11-22 | 1987-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-23 | 1990-11-22 | 1991-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-23 | 1994-11-22 | 1995-05-24 | $7700.00 | Window Closed / Lapsed |