US4902515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polylactide compositions
Assignee: EIDP Inc
•
Filing: 1988-10-12
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Granted: 1990-02-20
•
Expires: 2008-10-12
Abstract
Abstract Systems for delivery of biologically active materials employing novel polylactide composition containing segments of poly(R-lactide) interlocked with segments of poly(S-lactide) as the carrier.
Inventors
- 👤 Gary L. Loomis
- 👤 Joseph R. Murdoch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:25
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/06; C08G63/08; A; A61; A61K; A61K9/00; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; C08L; C08L67/00; C08L67/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
47 words
A process for encapsulating a biologically active ingredient in interlocked segments of poly(R-lactide) and poly(S-lactide) which comprises intimately contacting segments of poly(R-lactide) and poly(S-lactide) at a temperature below the melting temperature of the highest melting phase in the presence of the biologically active compound until interlocking occurs.
Claim 2
Dependent Claim
47 words
A process for encapsulating a biologically active ingredient in interlocked segments of poly(R-lactide) and poly(S-lactide) which comprises intimately contacting segments of poly(R-lactide) and poly(S-lactide) at a temperature below the melting temperature of the highest melting phase in the presence of the biologically active compound until interlocking occurs.
Claim 3
Dependent Claim
36 words
The process of claim 1 wherein the segments are interlocked by mixing solid poly(R-lactide), poly(S-lactide) and the biologically active compound and heating the combination at a temperature above the melting temperature of the lowest melting phase.
Claim 4
Dependent Claim
20 words
The process of claim 2 wherein the segments and biologically active compound are contacted by dissolving each in a solvent.
Claim 5
Dependent Claim
35 words
The process of claim 3 wherein the poly(R-lactide) segments, the poly(S-lact segments and the biologically active compound are dissolved in separate solvents and then the separate solutions are combined before the combined solvent is evaporated.
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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) | 1993-02-19 | 1993-08-21 | 1994-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-19 | 1997-08-21 | 1998-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-19 | 2001-08-21 | 2002-02-20 | $7700.00 | Window Closed / Lapsed |