US4587267A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled release system
Assignee: STC PLC
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Filing: 1984-09-13
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Granted: 1986-05-06
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Expires: 2004-09-13
Abstract
Abstract A device for the controlled release of an active material into an aqueous medium comprises a porous sintered body of a water soluble glass (11). The pores of the body are filled with a composition (12) consisting wholly or partially of an active material. The device may be provided with a low solubility coating (13). On immersion in an aqueous medium the glass (11) dissolves to become a sponge-like structure having a plurality of convoluted capillaries and from which the active material is released.
Inventors
- 👤 Cyril F. Drake
- 👤 Alfred J. Arch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:52
CPC Classifications
A; A61; A61M; A61M31/00; A61M31/002; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2009; G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/4163
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
82 words
A device for the controlled release of an active material into an aqueous medium in contact with the device, the device including a porous coherent body of a sintered particulate water soluble glass, the pores of said body being impregnated with a material comprising wholly or partially an active material, the device being such that, when contacted with the aqueous medium, the rate at which the active material is released into the medium is determined by the dissolution rate of the glass.
Claim 2
Independent Claim
82 words
A device for the controlled release of an active material into an aqueous medium in contact with the device, the device including a porous coherent body of a sintered particulate water soluble glass, the pores of said body being impregnated with a material comprising wholly or partially an active material, the device being such that, when contacted with the aqueous medium, the rate at which the active material is released into the medium is determined by the dissolution rate of the glass.
Claim 3
Dependent Claim
19 words
A device as claimed in claim 1 wholly or partly clad with a coating of relatively low dissolution rate.
Claim 4
Dependent Claim
15 words
A device as claimed in claim 1 or 2, wherein the active material includes selenium.
Claim 5
Dependent Claim
24 words
A device as claimed in claim 1 or 2, wherein the active material is selected from the group consisting of medicines and therapeutic agents.
Claim 6
Dependent Claim
14 words
A device as claimed in claim 4, wherein the active material is a hormone.
Claim 7
Dependent Claim
12 words
A device as claimed in claim 5, wherein the hormone is insulin.
Claim 8
Dependent Claim
12 words
A device as claimed in claim 5 wherein the hormone is progesterone.
Claim 9
Dependent Claim
17 words
A device as claimed in claim 1, wherein the active material includes a water snail attractant poison.
Claim 10
Dependent Claim
25 words
A device as claimed in claim 1, wherein the glass has a dissolution rate that is significantly dependent on the pH of an aqueous medium.
Claim 11
Independent Claim
115 words
A device for the controlled release of an active material into an aqueous medium in contact with the device, the device including a substantially insoluble tube open at at least one end and containing a composite material comprising a porous coherent body of a sintered particulate water soluble glass, the pores of said body being impregnated with a material comprising wholly or partially of an active material, wherein the dissolution rate of the glass is significantly less than that of the active material, the device being such that, when contacted with the aqueous medium, the rate at which the active material is released into the medium is determined by the dissolution rate of the glass.
Claim 12
Independent Claim
115 words
A device for the controlled release of an active material into an aqueous medium in contact with the device, the device including a substantially insoluble tube open at at least one end and containing a composite material comprising a porous coherent body of a sintered particulate water soluble glass, the pores of said body being impregnated with a material comprising wholly or partially of an active material, wherein the dissolution rate of the glass is significantly less than that of the active material, the device being such that, when contacted with the aqueous medium, the rate at which the active material is released into the medium is determined by the dissolution rate of the glass.
Claim 13
Dependent Claim
13 words
A pill, tablet or granule, incorporating a device as claimed in claim 1.
Claim 14
Dependent Claim
12 words
An implant or bolus incorporating a device as claimed in claim 1.
References Cited (Backward Citations)
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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) | 1989-05-05 | 1989-11-04 | 1990-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-05 | 1993-11-04 | 1994-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-05 | 1997-11-04 | 1998-05-06 | $7700.00 | Window Closed / Lapsed |