Patent US3927422A successfully refreshed from Google Patents.
US3927422A
Expired / Lapsed
US
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Prosthesis and method for making same
Assignee: Interface Biomedical Laboratories Corp
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Filing: 1973-12-12
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Granted: 1975-12-23
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Expires: 1993-12-12
Abstract
Abstract A tubular collagen vascular graft prosthesis is subjected to treatment so that its intimal surface has an increased net negative surface charge which prevents thrombosis. Treatment with succinic anhydride is shown as one way of accomplishing this. Valve grafts are likewise treated.
Inventors
- 👤 Philip Nicholas Sawyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:16
CPC Classifications
A; A61; A61L; A61L33/00; A61L33/0076; A61L33/0082
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
31 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof by a succinylation reaction.
Claim 2
Independent Claim
31 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof by a succinylation reaction.
Claim 3
Dependent Claim
19 words
A method as claimed in claim 1 wherein the collagen is prepared from ficin digested bovine carotid artery material.
Claim 4
Dependent Claim
16 words
A method as claimed in claim 1 wherein the prosthesis is formed as a vascular prosthesis.
Claim 5
Dependent Claim
15 words
A method as claimed in claim 1 wherein the prosthesis is formed as a valve.
Claim 6
Dependent Claim
8 words
A prosthesis made as claimed in claim 1.
Claim 7
Independent Claim
42 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen, the prosthesis including protein with free amino groups, and increasing the net negative surface charge of the intimal surface thereof by covering the free amino group.
Claim 8
Independent Claim
42 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen, the prosthesis including protein with free amino groups, and increasing the net negative surface charge of the intimal surface thereof by covering the free amino group.
Claim 9
Independent Claim
32 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof by thE following chemical reaction
Claim 10
Independent Claim
32 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof by thE following chemical reaction
Claim 11
Independent Claim
40 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof, said collagen being dialdehyde starch tanned collagen which is treated with succinic anhydride.
Claim 12
Independent Claim
40 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen and increasing the negative surface charge of the intimal surface thereof, said collagen being dialdehyde starch tanned collagen which is treated with succinic anhydride.
Claim 13
Dependent Claim
14 words
A method as claimed in claim 8 comprising further modifying said surface with phenylglyoxal.
Claim 14
Dependent Claim
15 words
A method as claimed in claim 8 comprising further modifying said surface with diethyl pyrocarbonate.
Claim 15
Independent Claim
64 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen, said graft being in the form of a collagen tube, comprising closing off an end of said tube, inserting said end into a fluid and inserting a liquid chemical succinylation reactant into the lumen of the tube to increase the negative surface charge of the intimal surface thereof.
Claim 16
Independent Claim
64 words
A method of improving the performance of a graft prosthesis comprising making the prosthesis of collagen, said graft being in the form of a collagen tube, comprising closing off an end of said tube, inserting said end into a fluid and inserting a liquid chemical succinylation reactant into the lumen of the tube to increase the negative surface charge of the intimal surface thereof.
Claim 17
Dependent Claim
18 words
A method as claimed in claim 11 wherein the chemical reactant is succinic anhydride in a basic solution.
Claim 18
Dependent Claim
38 words
A method as claimed in claim 12 wherein a NaHCO3 buffer solution is inserted into the lumen in sequential additions of approximately 10 ml. aliquots to which about 0.1 gm. of crystals of succinic anhydride were respectively added.
References Cited (Backward Citations)
US2900644A
Cited
US3609768A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |