EP0681843A2
Expired / Lapsed
EP
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Preparation of diagnostic agents
Assignee: Quadrant Drug Delivery Ltd
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Filing: 1992-04-10
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Granted: —
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Expires: 2012-04-10
Abstract
Abstract Microcapsules are prepared by spray-drying a solution or dispersion of a wall-forming material. Suitable wall-forming materials include proteins such as albumin and gelatin.
Inventors
- 👤 Andrew Derek Sutton
- 👤 Richard Alan Johnson
- 👤 Peter James Senior
- 👤 David Heath
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 16:53
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/22; A61K49/222; A61K49/223; A61K49/225; A61K9/00; A61K9/14; A61K9/16; A61K9/1682; A61K9/1688; A61K9/1694; A61K9/48; A61K9/50; A61K9/5089; B; B01; B01J; B01J13/00; B01J13/02; B01J13/04; B01J13/043; B01J13/06; B01J13/14; Y; Y10; Y10S; Y10S516/00; Y10S516/924; Y10S516/928
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
34 words
A process comprising the step of atomising a solution or dispersion of a wall-forming material in a liquid carrier into a gas in order to obtain hollow microcapsules by evaporation of the liquid carrier.
Claim 2
Dependent Claim
29 words
A process according to Claim 1 wherein the product obtained thereby is subjected to the further step of reducing the water-solubility of at least the outside of the microcapsules.
Claim 3
Dependent Claim
15 words
A process according to Claim 1 or 2 wherein the wall-forming material is a protein.
Claim 4
Dependent Claim
15 words
A process according to Claim 3 wherein the protein is collagen, gelatin or serum albumin.
Claim 5
Dependent Claim
24 words
A process according to Claim 4 wherein the protein is human serum albumin, or an analogue or fragment thereof, prepared by recombinant DNA techniques.
Claim 6
Dependent Claim
20 words
A process according to any one of Claims 3 to 6 wherein the protein solution or dispersion comprises 10.0-30.0% protein.
Claim 7
Dependent Claim
35 words
A process according to any one of Claims 3 to 6 wherein in the step of Claim 1 the protein solution or dispersion is atomised as said to form discrete microcapsules of 0.01-50.0 µm diameter.
Claim 8
Dependent Claim
24 words
A process according to any one of Claims 3 to 7 wherein the product of the process of Claim 1 comprises 96-98% monomeric protein.
Claim 9
Dependent Claim
32 words
A process according to any one of Claims 3 to 8 when dependent on Claim 2 wherein the product of the step of Claim 2 comprises no more than 5% monomeric protein.
Claim 10
Dependent Claim
32 words
A process according to any one of Claims 2 to 7 wherein the conditions of the step of Claim 1 are such as to achieve the step of Claim 2 substantially simultaneously.
Claim 11
Dependent Claim
14 words
Microcapsules obtained by a process according to any one of Claims 1 to 10.
Claim 12
Dependent Claim
14 words
Microcapsules obtainable by a process according to any one of Claims 1 to 10.
Claim 13
Dependent Claim
30 words
Hollow microspheres in which more than 30% of the microspheres have a diameter within a 2 µm range and at least 90% have a diameter within the range 1.0-8.0 µm.
Claim 14
Dependent Claim
26 words
Hollow microspheres in which the interquartile range of diameters is 2 µm or less and the median diameter is between 2.0 µm and 8.0 µm inclusive.
Claim 15
Dependent Claim
62 words
Hollow microspheres with proteinaceous walls in which at least 90% of the microspheres have a diameter in the range 1.0-8.0 µm; at least 90% of the microspheres have a wall thickness of 40-500 nm; and at least 50% of the protein in the walls of the microspheres is so cross-linked as to be resistant to extraction in 1% HCl for 2 mins.
Claim 16
Dependent Claim
17 words
Hollow microspheres according to Claim 15 wherein at least 95% of the protein is cross-linked as said.
Claim 17
Dependent Claim
41 words
Hollow microspheres predominantly of 1.0-10.0 µm in diameter, at least 10% of the microspheres, when suspended in water, being capable of surviving a 0.25 s application of a pressure of 2.66 x 10⁴ Pa without bursting, collapsing or filling with water.
Claim 18
Independent Claim
54 words
A method of generating an image for subsequent inspection, comprising (a) injecting into the body of a mammal microcapsules according to any one of Claims 11 to 17, (b) subjecting the mammal or part thereof to suitable ultrasonic radiation and (c) detecting ultrasonic radiation reflected, transmitted, resonated or frequency modulated by the said microcapsules.
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