Patent US5022745A successfully refreshed from Google Patents.
EP0190833A2
Expired / Lapsed
EP
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Method for producing microcapsule
Assignee: Takeda Pharmaceutical Co Ltd
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Filing: 1986-01-17
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Granted: —
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Expires: 2006-01-17
Abstract
Abstract Microcapsules are advantageously produced with a high take-up of a water-soluble drug by preparing a W/O emulsion composed of a water-soluble drug-containing solution as the inner aqueous phase and a polymer-containing solution as the oil phase, dispersing said emulsion in an aqueous phase and subjecting the resulting W/O/W emulsion to an in-water drying, wherein the viscosity of the W/0 emulsion used in preparing the W/O/W emulsion is adjusted to about 150 to about 10,000 centipoises.
Inventors
- 👤 Masaki Yamamoto
- 👤 Shigeyuki Takada
- 👤 Yasuaki Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 16:54
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5031; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; A61K9/1652; A61K9/1658; A61K9/1682; A61K9/1694; B; B01; B01J; B01J13/00; B01J13/02; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2987
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
72 words
A method of producing sustained-release microcapsules containing a water-soluble drug, which comprises preparing a W/O emulsion composed of a water-soluble drug-containing solution as the inner aqueous phase and a polymer-containing solution as the oil phase,adjusting the viscosity of the W/O emulsion used in preparing the W/O/W emulsion to from about 150 to about 10,000 centipoises, dispersing said emulsion in an aqueous phase and subjecting the resulting W/O/W emulsion to an in-water drying.
Claim 2
Independent Claim
72 words
A method of producing sustained-release microcapsules containing a water-soluble drug, which comprises preparing a W/O emulsion composed of a water-soluble drug-containing solution as the inner aqueous phase and a polymer-containing solution as the oil phase,adjusting the viscosity of the W/O emulsion used in preparing the W/O/W emulsion to from about 150 to about 10,000 centipoises, dispersing said emulsion in an aqueous phase and subjecting the resulting W/O/W emulsion to an in-water drying.
Claim 3
Dependent Claim
27 words
A method as claimed in Claim 1, wherein the viscosity of the W/O emulsion in preparing the W/O/W emulsion is adjusted to about 150 to 5,000 centipoises.
Claim 4
Dependent Claim
100 words
A method as claimed in Claim 1, wherein the viscosity of the W/O emulsion in preparing the W/O/W emulsion is adjusted to about 150 to about 10,000 centipoises by the procedure of increasing the polymer concentration in the oil phase; adjusting the ratio of the aqueous phase to the oil phase; adjusting the temperature of said W/O emulsion; adjusting the temperature of the external aqueous phase; adjusting the temperature of the W/O emulsion with a line heater or cooler or the like in infusing the W/O emulsion into the external aqueous phase; or carrying out the above procedure in combination.
Claim 5
Dependent Claim
63 words
A method as claimed in Claim 1, wherein the viscosity of the W/O emulsion in preparing the W/O/W emulsion is adjusted to about 150 to about 10,000 centipoises by the manner of regulating the temperatures of (i) the W/O emulsion or (ii) both'the W/O emulsion and the external aqueous phase to from about -20°C to the boiling point of the organic solvent used.
Claim 6
Dependent Claim
15 words
A method as claimed in Claim 4, wherein the temperature is about 0°C to 30°C.
Claim 7
Dependent Claim
16 words
A method as claimed in Claim 1, wherein the water-soluble drug is a biologically active polypeptide.
Claim 8
Dependent Claim
18 words
A method as claimed in Claim 6, wherein the biologically active polypeptide is (Pyr)Glu-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-Pro-NH-C 2 H 5 ·acetate.
Claim 9
Dependent Claim
13 words
A method as claimed in Claim 1, wherein the polymer is polylactic acid.
Claim 10
Dependent Claim
19 words
A method as claimed in Claim 1, wherein the polymer is a copolymer of lactic acid and glycolic acid.
Claim 11
Dependent Claim
31 words
A method as claimed in Claim 9, wherein the ratio of lactic acid : glycolic acid of the copolymer is about 75±2 mole % : about 25 ± 2 mole %.
References Cited (Backward Citations)
No citation records indexed.
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