US5073202A
Expired / Lapsed
US
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Method of using a biodegradable superabsorbing sponge
Assignee: Novavax Inc
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Filing: 1990-07-12
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Granted: 1991-12-17
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Expires: 2010-07-12
Abstract
Abstract A new superabsorber which gels and cross-links as hydrated has been developed. The superabsorber contains a branched-chain polyanionic carbohydrate such as carboxymethylcellulose, a cross-linking agent, and a hydrophobic carboxylic acid. The superabosrber is biodegradable and non-toxic.
Inventors
- 👤 Donald F. H. Wallach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:56
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/60; A61F; A61F13/00; A61F13/15; A61F13/15203; A61F13/15252; A61L15/22; A61L15/28; A61F13/51; A61F2013/51059; A61F2013/51061; A61F13/53; A61F2013/530481; A61F2013/530583; A61F2013/530649; A61F2013/530795; A61F13/534; A61F2013/53481; A61F13/84; A61F13/8405; A61F2013/8438; A61F2013/8447; A61F2013/8452
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
79 words
A method of absorbing an aqueous or saline solution using a biodegradable synthetic sponge composition comprising the steps of: providing said synthetic sponge composition in a substantially unhydrated form, said synthetic sponge composition containing a carboxylic acid with a substantial hydrophobic region, a separate cross-linking agent, and a branched complex carbohydrate; contacting said solution to be absorbed with said synthetic sponge composition; whereby said synthetic sponge composition hydrates to absorb said solution and cross-links into a gel substantially simultaneously.
Claim 2
Independent Claim
79 words
A method of absorbing an aqueous or saline solution using a biodegradable synthetic sponge composition comprising the steps of: providing said synthetic sponge composition in a substantially unhydrated form, said synthetic sponge composition containing a carboxylic acid with a substantial hydrophobic region, a separate cross-linking agent, and a branched complex carbohydrate; contacting said solution to be absorbed with said synthetic sponge composition; whereby said synthetic sponge composition hydrates to absorb said solution and cross-links into a gel substantially simultaneously.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein said carboxylic acid is selected from the group consisting of fatty acids, benzoic acid, and mixtures thereof.
Claim 4
Dependent Claim
24 words
The method of claim 2 wherein said fatty acid is selected from the group consisting of lauric, palmitic, and stearic acids, and mixtures thereof.
Claim 5
Dependent Claim
20 words
The method of claim 1 wherein said branched complex carbohydrate is selected from the group consisting of carboxymethylcellulose, and chitosan.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein said composition further comprises a linear carbohydrate.
Claim 7
Dependent Claim
34 words
The method of claim 1 wherein said cross-linking agent is selected from the group consisting of metallo-organic complexes containing aluminum ions, chromium ions, and other metal ions with a valence of at least 3.
Claim 8
Independent Claim
78 words
The method of entrapping particles in a gel comprising the steps of: providing a synthetic sponge composition in a substantially unhydrated form, said synthetic sponge composition containing a carboxylic acid with a substantial hydrophobic region, a separate cross-linking agent, and a branched complex carbohydrate; contacting a solution containing said particles to be entrapped with said synthetic sponge composition; whereby said gel is formed by the combined hydration and cross-linking of said synthetic sponge composition, thereby entrapping the particles.
Claim 9
Independent Claim
78 words
The method of entrapping particles in a gel comprising the steps of: providing a synthetic sponge composition in a substantially unhydrated form, said synthetic sponge composition containing a carboxylic acid with a substantial hydrophobic region, a separate cross-linking agent, and a branched complex carbohydrate; contacting a solution containing said particles to be entrapped with said synthetic sponge composition; whereby said gel is formed by the combined hydration and cross-linking of said synthetic sponge composition, thereby entrapping the particles.
Claim 10
Dependent Claim
23 words
The method of claim 7 wherein said carboxylic acid is selected from the group consisting of fatty acids, benzoic acid, and mixtures thereof.
Claim 11
Dependent Claim
22 words
The method of claim 7 wherein said particles to be entrapped are selected from the group consisting of cells, bacteria, and macromolecules.
Claim 12
Dependent Claim
24 words
The method of claim 7 wherein said fatty acid is selected from the group consisting of lauric, palmitic, and stearic acids, and mixtures thereof.
Claim 13
Dependent Claim
20 words
The method of claim 7 wherein said branched complex carbohydrate is selected from the group consisting of carboxymethylcellulose, and chitosan.
Claim 14
Dependent Claim
13 words
The method of claim 7 wherein said composition further comprises a linear carbohydrate.
Claim 15
Dependent Claim
34 words
The method of claim 7 wherein said cross-linking agent is selected from the group consisting of metallo-organic complexes containing aluminum ions, chromium ions, and other metal ions with a valence of at least 3.
Claim 16
Dependent Claim
25 words
The method of claim 7 wherein said entrapped particles are released over time from said gel, whereby said gel acts as a sustained release vehicle.
References Cited (Backward Citations)
CA1152483A
Cited
US4786415A
Cited
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