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US4405327A
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Method for inhibiting mineralization of natural tissue during implantation
Assignee: Medtronic Inc
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Filing: 1982-08-25
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Granted: 1983-09-20
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Expires: 2002-08-25
Abstract
Abstract Natural tissues fixed with a tanning solution such as glutaraldehyde and intended for implantation in humans, e.g., porcine heart valve prosthetic devices, are treated with a solution of a water soluble quaternary ammonium salt such as dodecyltrimethylammonium chloride to inhibit mineralizaton, particularly calcification, of the tissue after implantation.
Inventors
- 👤 Elisabeth M. Pollock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:58
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/36; A61L27/3683; A61L27/3687; A61L2400/00; A61L2400/02; Y; Y10; Y10S; Y10S623/00; Y10S623/915; Y10S623/916
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
51 words
A method for inhibiting the mineralization of fixed natural tissue after implantation in a living body comprising contacting fixed natural tissue intended for implantation with an aqueous solution of a water soluble quaternary ammonium salt whose nitrogen atom has at least one alkyl group containing from 7 to 15 carbon atoms.
Claim 2
Independent Claim
51 words
A method for inhibiting the mineralization of fixed natural tissue after implantation in a living body comprising contacting fixed natural tissue intended for implantation with an aqueous solution of a water soluble quaternary ammonium salt whose nitrogen atom has at least one alkyl group containing from 7 to 15 carbon atoms.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein the aqueous solution has a pH of from about 2.0 to about 10.0.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein the counter-ion of the quaternary ammonium salt is selected from the group consisting of chloride ion and methylsulfate ion.
Claim 5
Dependent Claim
15 words
The method of claim 1 wherein the substituent group is a straight chain aliphatic group.
Claim 6
Dependent Claim
14 words
The method of claim 1 wherein the substituent group is a branched aliphatic group.
Claim 7
Dependent Claim
26 words
The method of claim 1 wherein the water soluble quaternary ammonium salt is selected from the group consisting of decyltrimethylammonium chloride, dodecyltrimethylammonium chloride and myristyltrimethylammonium chloride.
Claim 8
Dependent Claim
28 words
The method of claim 1 wherein said natural tissue is contacted with said solution for a time sufficient to effectively inhibit future calcification of said tissue after implantation.
Claim 9
Dependent Claim
24 words
The method of claim 1 wherein said tissue is contacted with said solution for a period of at least 24 hours at ambient temperature.
Claim 10
Dependent Claim
22 words
The method of claim 1 wherein the concentration of said salt in said solution is from about 0.1 to 5% by weight.
Claim 11
Dependent Claim
53 words
The method of claim 1 wherein said solution comprises, in addition to said quaternary ammonium salt, up to about 1% by weight of sodium chloride, up to about 0.05% by weight each of potassium chloride, magnesium sulfate heptahydrate and dipotassium hydrogen phosphate, and up to about 0.1% by weight of sodium dihydrogen phospate.
Claim 12
Dependent Claim
52 words
The method of claim 1 wherein said solution comprises, in addition to said quaternary ammonium salt, about 0.8% by weight of sodium chloride, about 0.04% by weight of potassium chloride, about 0.02% by weight each of magnesium sulfate heptahydrate and dipotassium hydrogen phospate, and about 0.08% by weight of sodium dihydrogen phospate.
Claim 13
Dependent Claim
14 words
The method of claim 11 wherein the solution has a pH of about 7.
Claim 14
Independent Claim
44 words
A method for inhibiting the calcification of fixed natural tissue after implantation in a living body which comprises contacting fixed tissue intended for implantation with a solution comprising dodecyltrimethylammmonium chloride for a time sufficient to effectively inhibit future calcification of said tissue after implantation.
Claim 15
Independent Claim
44 words
A method for inhibiting the calcification of fixed natural tissue after implantation in a living body which comprises contacting fixed tissue intended for implantation with a solution comprising dodecyltrimethylammmonium chloride for a time sufficient to effectively inhibit future calcification of said tissue after implantation.
Claim 16
Dependent Claim
18 words
The method of claim 13 wherein said solution comprises from about 0.1 to 5% by weight dodecyltrimethylammonium chloride.
Claim 17
Dependent Claim
22 words
The method of claim 13 wherein said tissue is contacted with said solution for a time of at least about 7 days.
Claim 18
Dependent Claim
53 words
The method of claim 13 wherein said solution comprises, in addition to said quaternary ammonium salt, up to about 1% by weight of sodium chloride, up to about 0.05% by weight each of potassium chloride, magnesium sulfate heptahydrate and dipotassium hydrogen phosphate, and up to about 0.1% by weight of sodium dihydrogen phosphate.
Claim 19
Dependent Claim
52 words
The method of claim 13 wherein said solution comprises, in addition to said quaternary ammonium salt, about 0.8% by weight of sodium chloride, about 0.04% by weight of potassium chloride, about 0.02% by weight each of magnesium sulfate heptahydrate and dipotassium hydrogen phoshpate, and about 0.08% by weight of sodium dihydrogen phosphate.
Claim 20
Dependent Claim
14 words
The method of claim 17 wherein the pH of said solution is about 7.0.
Claim 21
Dependent Claim
14 words
The method of claim 18 wherein the concentration of dodecyltrimethylammonium chloride is about 1%.
Claim 22
Dependent Claim
26 words
The method of claim 19 wherein the tissue is contacted with said solution of dodecyltrimethylammonium chloride for a period of about 7 days at ambient temperature.
Claim 23
Dependent Claim
15 words
The method of claim 13 wherein the fixed tissue is a glutaraldehyde-fixed porcine heart valve.
Claim 24
Dependent Claim
12 words
The method of claim 13 wherein said living body is a human.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-19 | 1987-03-21 | 1987-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-19 | 1991-03-21 | 1991-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-19 | 1995-03-21 | 1995-09-20 | $7700.00 | Window Closed / Lapsed |