US4808707A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chitosan alginate capsules
Assignee: DELAWARE A NOT FOR PROFIT Corp OF, University of
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Filing: 1987-06-08
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Granted: 1989-02-28
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Expires: 2007-06-08
Abstract
Abstract The permeability of the walls of chitosan alginate capsules is adjusted by substituting with esterified alginic acid a portion of the metal alginate normally used in the fabrication of such capsules.
Inventors
- 👤 Mary M. Daly
- 👤 Robert W. Keown
- 👤 Dietrich W. Knorr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:55
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/4816
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
26 words
A capsule of chitosan alginate wherein said alginate is 10 to 60% esterified with 1,2-propylene glycol to increase the permeability of the walls of said capsule.
Claim 2
Dependent Claim
26 words
A capsule of chitosan alginate wherein said alginate is 10 to 60% esterified with 1,2-propylene glycol to increase the permeability of the walls of said capsule.
Claim 3
Dependent Claim
11 words
The capsule of claim 1 wherein the alginate is 30% esterified.
Claim 4
Dependent Claim
9 words
The capsule of claim 1 hardened with calcium chloride.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-28 | 1992-08-29 | 1993-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-28 | 1996-08-29 | 1997-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-28 | 2000-08-29 | 2001-02-28 | $7700.00 | Window Closed / Lapsed |