US4900540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lipisomes containing gas for ultrasound detection
Assignee: University of Massachusetts System
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Filing: 1983-06-20
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Granted: 1990-02-13
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Expires: 2003-06-20
Abstract
Abstract Phospholipid liposomes are provided having a lipid bilayer surrounding a confined composition which includes a gas or a gas precursor. The liposomes can be administered to a patient and can be detected in vivo by ultrasound techniques which permit organ imaging.
Inventors
- 👤 Patrick J. Ryan
- 👤 Michael A. Davis
- 👤 Donald L. Melchior
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:43
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/22; A61K49/222; A61K49/227; Y; Y10; Y10S; Y10S436/00; Y10S436/829
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
46 words
Phospholipid liposomes, for use as an ultrasound contrast medium, comprising an outer phospholipid layer and, confined by said layer a gas precursor selected from the group consisting of aqueous sodium bicarbonate and aqueous aminomalonate in an amount effective to form a gas under physiological pH conditions.
Claim 2
Dependent Claim
46 words
Phospholipid liposomes, for use as an ultrasound contrast medium, comprising an outer phospholipid layer and, confined by said layer a gas precursor selected from the group consisting of aqueous sodium bicarbonate and aqueous aminomalonate in an amount effective to form a gas under physiological pH conditions.
Claim 3
Dependent Claim
13 words
The liposomes of claim 1 wherein said gas precursor is aqueous sodium bicarbonate.
Claim 4
Dependent Claim
11 words
The liposomes of claim 1 wherein said gas precursor is aminomalonate.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1993-02-12 | 1993-08-14 | 1994-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-12 | 1997-08-14 | 1998-02-13 | $3760.00 | Window Closed / Lapsed |
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