Patent US6015546A successfully refreshed from Google Patents.
US6015546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of further diagnostic agents
Assignee: Quadrant Drug Delivery Ltd
•
Filing: 1995-06-05
•
Granted: 2000-01-18
•
Expires: 2015-06-05
Abstract
Abstract Microcapsules are prepared by a process comprising the steps of (i) spray-drying a solution or dispersion of a wall-forming material in order to obtain intermediate microcapsules and (ii) reducing the water-solubility of at least the outside of the intermediate microcaspsules. Suitable wall-forming materials include proteins such as albumin and gelatin. The microcapsules have walls of 40-500 nm thick and are useful in ultrasonic imaging. The control of median size, size distribution and degree of insolubilization and cross-linking of the wall-forming material allows novel microsphere preparations to be produced.
Inventors
- 👤 Andrew Derek Sutton
- 👤 Richard Alan Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:39
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5052; A61K47/00; A61K47/30; A61K47/42; A61K49/00; A61K49/22; A61K49/222; A61K49/223; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1658; A61K9/5031
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
89 words
A process comprising the step of atomizing a solution or dispersion of a proteinaceous wall-forming material in a liquid carrier into a gas in order to obtain gas- or vapor-filled microcapsules by evaporation of the liquid carrier, wherein said microcapsules comprise a poloxamer which, following introduction into the human bloodstream, directs said microcapsules away from the reticulo-endothelial system and/or reduces opsonization of said microcapsules, such that said microcapsules have an in vivo t 1/2 of at least 5 minutes in the blood or in tissue perfused by the blood.
Claim 2
Dependent Claim
89 words
A process comprising the step of atomizing a solution or dispersion of a proteinaceous wall-forming material in a liquid carrier into a gas in order to obtain gas- or vapor-filled microcapsules by evaporation of the liquid carrier, wherein said microcapsules comprise a poloxamer which, following introduction into the human bloodstream, directs said microcapsules away from the reticulo-endothelial system and/or reduces opsonization of said microcapsules, such that said microcapsules have an in vivo t 1/2 of at least 5 minutes in the blood or in tissue perfused by the blood.
Claim 3
Dependent Claim
15 words
A process according to claim 1 wherein said protein is collagen, gelatin or serum albumin.
Claim 4
Dependent Claim
28 words
A process according to claim 2 wherein said protein is human serum albumin, or an analog or fragment thereof, derived from serum or prepared by recombinant DNA techniques.
Claim 5
Dependent Claim
15 words
A process according to claim 2 wherein said protein solution or dispersion comprises 10.0-30.0% protein.
Claim 6
Dependent Claim
13 words
A process according to claim 2 wherein said microcapsules comprise 96-98% monomeric protein.
Claim 7
Dependent Claim
27 words
A process according to claim 1 wherein said microcapsules are subjected to a further step of reducing the water-solubility of at least the outside of said microcapsules.
Claim 8
Dependent Claim
20 words
A process according to claim 6 wherein said steps of forming said microcapsules and reducing their water-solubility are substantially simultaneous.
Claim 9
Dependent Claim
17 words
A process according to claim 6 wherein said water-solubility-reduced microcapsules comprise no more than 5% monomeric protein.
Claim 10
Dependent Claim
15 words
A process according to claim 1 wherein said poloxamer is poloxamer 338, 407, or 908.
References Cited (Backward Citations)
US2797201A
Cited
US3501419A
Cited
US3565559A
Cited
GB1288583A
Cited
US4173488A
Cited
US3781230A
Cited
US3960583A
Cited
US4107288A
Cited
US4127622A
Cited
US4089800A
Cited
US4102806A
Cited
US4276885A
Cited
US4316391A
Cited
JPS56129035A
Cited
EP0052575A2
Cited
US4442843A
Cited
US4420442A
Cited
US4466442A
Cited
EP0091555A1
Cited
US4960351A
Cited
US4718433A
Cited
WO1984002838A1
Cited
US4900540A
Cited
EP0131540A2
Cited
EP0224934A2
Cited
US4774958A
Cited
US4904479A
Cited
US5069936A
Cited
US4844882A
Cited
EP0324938A1
Cited
NZ227869A
Cited
EP0327490A1
Cited
US4981625A
Cited
US4957656A
Cited
US5370861A
Cited
US5543162A
Cited
WO1990013780A1
Cited
WO1991006286A1
Cited
US5271961A
Cited
JPH04506931A
Cited
WO1991009629A1
Cited
CA2036107A1
Cited
US5501863A
Cited
WO1991012823A1
Cited
US4968562A
Cited
WO1991015244A2
Cited
US5658551A
Cited
US5643553A
Cited
US5567414A
Cited
US5380519A
Cited
US5271928A
Cited
FR2660864A1
Cited
WO1991016080A1
Cited
US5137928A
Cited
EP0458079A2
Cited
US5190982A
Cited
US5205287A
Cited
EP0458745A1
Cited
AU8029791A
Cited
US5215680A
Cited
JPH04145131A
Cited
EP0494615A1
Cited
WO1992017213A1
Cited
WO1992017212A1
Cited
JPH06507884A
Cited
US5547656B1
Cited
US5547656A
Cited
WO1992018164A1
Cited
US5147631A
Cited
WO1993002712A1
Cited
US5196183A
Cited
EP0554213A1
Cited
US5674468A
Cited
EP0611567A1
Cited
EP0606486A1
Cited
US5498421A
Cited
US5605673A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-01-17 | 2003-07-19 | 2004-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-01-17 | 2007-07-19 | 2008-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-01-17 | 2011-07-19 | 2012-01-18 | $7700.00 | Window Closed / Lapsed |