Patent US4193813A successfully refreshed from Google Patents.
US4193813A
Expired / Lapsed
US
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Method for making collagen sponge
Assignee: Medi-Coll Inc
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Filing: 1976-09-07
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Granted: 1980-03-18
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Expires: 1996-09-07
Abstract
Abstract Method for making a collagen sponge including the following steps. Native collagen form of fibrillar protein is comminuted and homogenized in an acid environment; noncollagenous material is removed and residual collagen is mixed with water the pH of the resulting slurry is adjusted to 4.5 to 5.0 by the addition of acetic acid; gluteraldehyde is then added and the slurry poured into molds and frozen at approximately -10° centigrade for approximately 20 hours. The frozen mass is then thawed, washed, and immersed in a wash of pH 8 to 9 for approximately 2 hours at 20° centigrade. Sufficient reducing agent is added to the wash to create excess reducing equivalents. The sponge is then immersed in a buffer solution of pH 4 to 5 for a time sufficient to equilibrate to uniform pH. The sponge formed by the above method is then moistended and self-administered in the upper vault of the vagina proximal to the cervix. The sponge is then retained for a desired period, usually several days to one month.
Inventors
- 👤 Milos Chvapil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:31
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0012; A61K9/0034; A61K9/0036; Y; Y10; Y10S; Y10S128/00; Y10S128/08
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
127 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into a homogeneous slurry, the improvement comprising: in the folowing sequence (a) adjusting the pH of said slurry to from pH 3.5 to pH 6.5; (b) adding from 0.5% to 1% of an aldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from 0° centigrade to -20° centigrade; (d) thawing said slurry to form collagenous sponge; and (e) immersing said sponge in a reducing wash having a pH of from 8 to 9 containing sufficient reducing agent to create excess reducing equivalents for a time, and at a temperature sufficient to reduce the existing double bond Schiff base to a single bond.
Claim 2
Dependent Claim
127 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into a homogeneous slurry, the improvement comprising: in the folowing sequence (a) adjusting the pH of said slurry to from pH 3.5 to pH 6.5; (b) adding from 0.5% to 1% of an aldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from 0° centigrade to -20° centigrade; (d) thawing said slurry to form collagenous sponge; and (e) immersing said sponge in a reducing wash having a pH of from 8 to 9 containing sufficient reducing agent to create excess reducing equivalents for a time, and at a temperature sufficient to reduce the existing double bond Schiff base to a single bond.
Claim 3
Dependent Claim
19 words
The improved method of claim 1 including adjusting the pH of said slurry to from pH 4.5 to 5.0.
Claim 4
Dependent Claim
20 words
The improved method of claim 1 including freezing said slurry at a temperature of from -5° centrigrade to -10° centigrade.
Claim 5
Dependent Claim
10 words
A collagen product formed by the method of claim 1.
Claim 6
Dependent Claim
120 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into an homogenous slurry, the improvement comprising: (a) adjusting the pH of said slurry from pH 4.5 to pH 5.0; (b) adding 0.5% to 1% of glutaraldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from -5° centigrade to -10° centigrade; (d) thawing said slurry to form a collagenous sponge; (e) immersing said sponge in a reducing wash having a pH of 8 to 9 and containing sufficient sodium borohydride to create excess reducing equivalents for a time, and at a temperature, sufficient to reduce the existing double bond Schiff base to a single bond.
Claim 7
Dependent Claim
120 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into an homogenous slurry, the improvement comprising: (a) adjusting the pH of said slurry from pH 4.5 to pH 5.0; (b) adding 0.5% to 1% of glutaraldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from -5° centigrade to -10° centigrade; (d) thawing said slurry to form a collagenous sponge; (e) immersing said sponge in a reducing wash having a pH of 8 to 9 and containing sufficient sodium borohydride to create excess reducing equivalents for a time, and at a temperature, sufficient to reduce the existing double bond Schiff base to a single bond.
Claim 8
Dependent Claim
10 words
A collagen product formed by the method of claim 5.
Claim 9
Dependent Claim
154 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into a homogenous slurry, the improvement comprising: in the following sequence (a) adjusting the pH of said slurry to from pH 3.5 to pH 6.5; (b) adding from 0.5% to 1% of an aldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from 0° centigrade to -20° centigrade; (d) thawing said slurry to form a collagneous sponge; (e) immersing said sponge in a reducing wash having a pH of from 8 to 9 containing sufficient reducing agent to create excess reducing equivalents fro a time, and at a temperature sufficient to reduce the existing double bond Schiff base to a single bond; (f) immersing said sponge in a buffer solution for a time and at a temperature to equilibrate the pH of the sponge of pH 4.0 to 6.5.
Claim 10
Dependent Claim
154 words
In a method of making a collagenous product wherein comminuted collagen is suspended in water and formed into a homogenous slurry, the improvement comprising: in the following sequence (a) adjusting the pH of said slurry to from pH 3.5 to pH 6.5; (b) adding from 0.5% to 1% of an aldehyde based on the total volume of said slurry; (c) freezing said slurry at a temperature of from 0° centigrade to -20° centigrade; (d) thawing said slurry to form a collagneous sponge; (e) immersing said sponge in a reducing wash having a pH of from 8 to 9 containing sufficient reducing agent to create excess reducing equivalents fro a time, and at a temperature sufficient to reduce the existing double bond Schiff base to a single bond; (f) immersing said sponge in a buffer solution for a time and at a temperature to equilibrate the pH of the sponge of pH 4.0 to 6.5.
Claim 11
Dependent Claim
20 words
The improved method of claim 7 including adjusting the pH of said slurry to from pH 4.5 to pH 5.0.
Claim 12
Dependent Claim
20 words
The improved method of claim 7 including freezing said slurry at a temperature of from -5° centigrade to -10° centigrade.
Claim 13
Dependent Claim
41 words
The improved method of claim 7 including immersing said sponge in a buffer solution having a pH of from 4.0 to 5.0 for a time, and at a temperature to equilibrate the pH of the sponge to pH 4.0 to 6.5.
Claim 14
Dependent Claim
52 words
The improved mmethod of claim 7 including immersing said sponge in a reducing wash having a pH of from 8.0 to 9.0 and containing sufficient sodium borohydride to create excess reducing equivalents for a time, and at a temperature, sufficient to reduce the existing double bond Schiff base to a single bond.
Claim 15
Dependent Claim
10 words
A collagen product formed by the method of claim 7.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-03-18 | 1983-09-17 | 1984-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-18 | 1987-09-17 | 1988-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-18 | 1991-09-17 | 1992-03-18 | $7700.00 | Window Closed / Lapsed |