US5333613A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microparticles as ultrasonic contrast media
Assignee: Delineate
•
Filing: 1993-03-23
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Granted: 1994-08-02
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Expires: 2013-03-23
Abstract
Abstract Ultrasonic contrast media are provided comprising small particles with entrapped gas, where the compositions can be selected for rapid dissolution with production of microbubbles or maintaining the gas in microtubules, microchambers or microcracks, providing for echogenicity. The particles are readily formed by precipitation from a liquid, either solution or melt, of a monomeric material, followed by drying and mechanically reducing the size of the particles.
Inventors
- 👤 Ernest G. Tickner
- 👤 Robert E. Short
- 👤 David H. Rammler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:14
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/22; A61K49/222; A61K49/223
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
118 words
In a method for ultrasonic scanning comprising introducing an echogenic material into a liquid containing chamber; isonating said chamber with ultrasonic sound; and detecting echoes from said chamber as a result of said echogenic material to determine characteristics of the walls of said chamber or of the fluid in said chamber, the improvement which comprises: said echogenic material being individual matrix particles, characterized by being comprised of low molecular weight physiologically acceptable amino acids capable of forming microparticles with entrapment of gas as microtubules, microchambers, and/or microcracks; and either capable of rapid dissolution in said liquid with release of microbubbles which retain a size to be visualized by standard ultrasonic techniques; or by slow dissolution in said liquid.
Claim 2
Dependent Claim
118 words
In a method for ultrasonic scanning comprising introducing an echogenic material into a liquid containing chamber; isonating said chamber with ultrasonic sound; and detecting echoes from said chamber as a result of said echogenic material to determine characteristics of the walls of said chamber or of the fluid in said chamber, the improvement which comprises: said echogenic material being individual matrix particles, characterized by being comprised of low molecular weight physiologically acceptable amino acids capable of forming microparticles with entrapment of gas as microtubules, microchambers, and/or microcracks; and either capable of rapid dissolution in said liquid with release of microbubbles which retain a size to be visualized by standard ultrasonic techniques; or by slow dissolution in said liquid.
Claim 3
Dependent Claim
19 words
A method according to claim 1, wherein said matrix particles are anhydrous and said amino acids exist as hydrates.
Claim 4
Dependent Claim
14 words
A method according to claim 1, wherein said amino acids are asparagine or proline.
Claim 5
Dependent Claim
43 words
A method according to claim 1, wherein said matrix particles are produced by dissolving said amino acids in a solvent at an elevated temperature; precipitating said amino acids from said solvent by at least one of evaporation or cooling; and removing residual solvent.
Claim 6
Dependent Claim
14 words
A method according to claim 7, wherein said amino acids are proline or asparagine.
Claim 7
Dependent Claim
42 words
A method according to claim 1, wherein said matrix particles are produced by melting said amino acids by heating said amino acids above their melting point; and cooling said amino acids while sonicating said amino acids to produce microtubules of entrapped gas.
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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) | 1997-08-01 | 1998-01-31 | 1998-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-01 | 2002-01-31 | 2002-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-01 | 2006-01-31 | 2006-08-02 | $7700.00 | Window Closed / Lapsed |