US4614794A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protein/polysaccharide complexes
Assignee: Johnson and Johnson
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Filing: 1984-09-24
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Granted: 1986-09-30
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Expires: 2004-09-24
Abstract
Abstract Complexes of polyanionic plant polysaccharides with biodegradable proteins, or proteolytic degradation products thereof, are useful in the formation of wound dressings and surgical implants, such as sutures, blood vessel grafts, and artificial organs. The biodegradable protein is preferably collagen, and the polysaccharide is preferably sodium alginate. The complexes are preferably formed by combining the protein and the polysaccharide at a pH which is no higher than the isoelectric point of the protein. The complexes may be crosslinked, such as by dehydrothermal crosslinking or by the use of chemical crosslinking agents such as aldehydes or carbodiimides. Multivalent cations may also be incorporated in the complex in order to give added strength.
Inventors
- 👤 Ian A. Easton
- 👤 Stephen D. Gorham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:22
CPC Classifications
C; C08; C08H; C08H1/00; C08H1/06; A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/225; A61L17/00; A61L17/06; A61L17/08; A61L27/00; A61L27/14; A61L27/22; A61L27/24; A61L27/26; C08B; C08B37/00; C08B37/006; C08B37/0084; A61F; A61F2310/00; A61F2310/00005; A61F2310/00365
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
59 words
A process for forming a porous protein/polysaccharide complex, said process comprising treating a solution containing less than 2% w/v of a biodegradable protein, or a hydrolytic degradation product thereof, with a polyanionic plant polysaccharide at a pH which is no higher than the isoelectric pH of said protein or degradation product to precipitate the complex and freeze-drying the complex.
Claim 2
Dependent Claim
59 words
A process for forming a porous protein/polysaccharide complex, said process comprising treating a solution containing less than 2% w/v of a biodegradable protein, or a hydrolytic degradation product thereof, with a polyanionic plant polysaccharide at a pH which is no higher than the isoelectric pH of said protein or degradation product to precipitate the complex and freeze-drying the complex.
Claim 3
Dependent Claim
12 words
A process according to claim 1, wherein the biodegradable protein is collagen.
Claim 4
Dependent Claim
12 words
A process according to claim 1 wherein the polysaccharide is an alginate.
Claim 5
Dependent Claim
14 words
A process according to claim 3, wherein said solution contains less than 1% w/v.
Claim 6
Dependent Claim
14 words
A process according to claim 4, wherein said solution contains less than 0.5% w/v.
Claim 7
Dependent Claim
15 words
A process according to claim 5, wherein said solution contains from 0.3 to 0.35% w/v.
Claim 8
Dependent Claim
19 words
A process according to claim 1 wherein the protein constitutes from 50 to 99% by weight of the complex.
Claim 9
Dependent Claim
19 words
A process according to claim 7 wherein the protein constitutes from 50 to 80% by weight of the complex.
Claim 10
Dependent Claim
17 words
A process according to claim 1 wherein said complex is blast frozen prior to said freeze-drying step.
Claim 11
Dependent Claim
27 words
A porous complex of a biodegradable protein, or a proteolytic degradation product thereof, with a polyanionic plant polysaccharide, and having a pore size greater than 20 microns.
Claim 12
Dependent Claim
27 words
A porous complex of a biodegradable protein, or a proteolytic degradation product thereof, with a polyanionic plant polysaccharide, and having a pore size greater than 20 microns.
Claim 13
Dependent Claim
11 words
A complex according to claim 10 wherein said protein is collagen.
Claim 14
Dependent Claim
12 words
A complex according to claim 10 wherein the polysaccharide is an alginate.
Claim 15
Dependent Claim
14 words
A complex according to claim 10 having a pore size greater than 50 microns.
Claim 16
Dependent Claim
14 words
A complex according to claim 13 having a pore size greater than 100 microns.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-09-29 | 1990-03-31 | 1990-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-29 | 1994-03-31 | 1994-09-30 | $3760.00 | Window Closed / Lapsed |
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