US4767619A
Expired / Lapsed
US
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Burn wound dressing material
Assignee: Department of National Defence
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Filing: 1986-08-11
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Granted: 1988-08-30
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Expires: 2006-08-11
Abstract
Abstract The invention disclosed is a burn wound-adherent dressing material comprising a complex of gelatin and a water-soluble resin material such as polyethylenimine. The dressing material may be in the form of a preformed film or in the form of an aqueous coating which sets to a gel and dries to a continuous wound-adherent film in situ.
Inventors
- 👤 Douglas G. Murray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:21
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/22; A61L15/225; A61F; A61F13/00; A61F13/02; A61F13/0246; A61F13/0253; A61F13/0276; A61F13/0289; A61L26/00; A61L26/0009; A61L26/0052; A61F2013/00089; A61F2013/00157; A61F2013/00182; A61F2013/00361; A61F2013/00365; A61F2013/00519; A61F2013/00655; A61F2013/00719; A61F2013/00846
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
50 words
A burn wound-adherent dressing material in the form of a continuous, wound-adherent, preformed film comprising a complex of gelatin of a Bloom # of 80 to 350 and a water-soluble polyethylenimine of molecular weight of 10,000 to 100,000, in a weight ratio of gelatin to polyethylenimine of 9:1 to 3:7.
Claim 2
Dependent Claim
50 words
A burn wound-adherent dressing material in the form of a continuous, wound-adherent, preformed film comprising a complex of gelatin of a Bloom # of 80 to 350 and a water-soluble polyethylenimine of molecular weight of 10,000 to 100,000, in a weight ratio of gelatin to polyethylenimine of 9:1 to 3:7.
Claim 3
Dependent Claim
19 words
A burn wound dressing according to claim 1, wherein the weight ratio of gelatin to polyethylenimine is about 1:1.
Claim 4
Dependent Claim
29 words
A burn wound dressing according to claim 2, wherein the gelatin has a Bloom # of about 150 and the polyethylenimine has a molecular weight of 40,000 to 60,000.
Claim 5
Dependent Claim
20 words
A burn wound dressing according to claim 3, wherein the thickness of the continuous film is 0.05 to 0.35 mm.
Claim 6
Dependent Claim
20 words
A burn wound dressing according to claim 4, wherein the thickness of the continuous film is 0.15 to 0.20 mm.
Claim 7
Dependent Claim
13 words
A burn wound dressing according to claim 1, additionally comprising a compatible plasticizer.
Claim 8
Dependent Claim
13 words
A burn wound dressing according to claim 6, wherein the plasticizer is glycerol.
Claim 9
Dependent Claim
19 words
A burn wound dressing according to claim 7, wherein the weight ratio of gelatin to polyethylenimine is about 1:1.
Claim 10
Dependent Claim
29 words
A burn wound dressing according to claim 8, wherein the gelatin has a Bloom # of about 150 and the polyethylenimine has a molecular weight of 40,000 to 60,000.
Claim 11
Dependent Claim
18 words
A burn wound dressing according to claim 9, wherein the thickness of the film is about 0.13 mm.
Claim 12
Dependent Claim
21 words
A burn wound dressing according to claim 10, wherein the weight ratio of gelatin to polyethylenimine to glycerol is about 5:5:2.
Claim 13
Independent Claim
111 words
A method for making a continuous burn wound-adherent preformed film dressing material, comprising the steps of: (a) dissolving gelatin of a Bloom # of 80 to 350 and an aqueous solution of polyethlenimine of molecular weight of 10,000 to 100,000 in distilled water and mixing to form a gelatin/polyethylenimine complex in a weight ratio of gelatin to polyethylenimine of 9:1 to 3:7; (b) adjusting the pH of the resulting aqueous solution by adding a suitable acid to lower the pH of the solution to 7-9.5; (c) pouring the solution onto a flat surface; and (d) drying in air at room temperature to form a gelatin/polyethylenimine complex continuous, burn wound-adherent preformed film.
Claim 14
Independent Claim
111 words
A method for making a continuous burn wound-adherent preformed film dressing material, comprising the steps of: (a) dissolving gelatin of a Bloom # of 80 to 350 and an aqueous solution of polyethlenimine of molecular weight of 10,000 to 100,000 in distilled water and mixing to form a gelatin/polyethylenimine complex in a weight ratio of gelatin to polyethylenimine of 9:1 to 3:7; (b) adjusting the pH of the resulting aqueous solution by adding a suitable acid to lower the pH of the solution to 7-9.5; (c) pouring the solution onto a flat surface; and (d) drying in air at room temperature to form a gelatin/polyethylenimine complex continuous, burn wound-adherent preformed film.
Claim 15
Dependent Claim
13 words
A method according to claim 12, wherein the suitable acid is hydrochloric acid.
Claim 16
Dependent Claim
15 words
A method according to claim 13, wherein the pH is adjusted to about pH 9.
Claim 17
Dependent Claim
17 words
A method according to claim 14, wherein the weight ratio of gelatin to PEI is about 1:1.
Claim 18
Dependent Claim
27 words
A method according to claim 15, wherein the gelatin has a Bloom # of about 150 and the polyethylenimine has a molecular weight of 40,000 to 60,000.
Claim 19
Independent Claim
136 words
A method of preparing a burn-wound dressing material in the form of a substantially uniform, aqueous coating comprising a complex of gelatin of a Bloom # of 80 to 350 and a water-soluble polyethylenimine of molecular weight of 10,000 to 100,000, in a weight ratio of gelatin to polyethylenimine of 7:3 to 3:7 comprising the steps of (a) providing an aqueous solution of said gelatin; (b) providing an aqueous solution of said polyethylenimine; (c) mixing solutions from (a) and (b) to form said aqueous gelatin/polyethylenimine complex; (d) applying the aqueous complex at a temperature of about 30° C. to a burn wound; (e) spreading the aqueous complex substantially uniformly over the surface of the wound; and (f) permitting the aqueous complex to set to a gel and dry to a continuous burn wound-adherent film in situ.
Claim 20
Independent Claim
136 words
A method of preparing a burn-wound dressing material in the form of a substantially uniform, aqueous coating comprising a complex of gelatin of a Bloom # of 80 to 350 and a water-soluble polyethylenimine of molecular weight of 10,000 to 100,000, in a weight ratio of gelatin to polyethylenimine of 7:3 to 3:7 comprising the steps of (a) providing an aqueous solution of said gelatin; (b) providing an aqueous solution of said polyethylenimine; (c) mixing solutions from (a) and (b) to form said aqueous gelatin/polyethylenimine complex; (d) applying the aqueous complex at a temperature of about 30° C. to a burn wound; (e) spreading the aqueous complex substantially uniformly over the surface of the wound; and (f) permitting the aqueous complex to set to a gel and dry to a continuous burn wound-adherent film in situ.
Claim 21
Dependent Claim
17 words
A method according to claim 17, wherein the gelatin and polyethylenimine components are maintained apart until use.
Claim 22
Dependent Claim
25 words
A method according to claim 18, wherein the aqueous gelatin/polyethylenimine complex comprises 36.5 to 40 parts of gelatin plus polyethylenimine per 100 parts of water.
Claim 23
Dependent Claim
16 words
A method according to claim 17, wherein the pH of the aqueous gelatin/polyethylenimine complex is 8-10.5.
Claim 24
Dependent Claim
15 words
A method according to claim 18, wherein the pH of the PEI solution is 8-11.
Claim 25
Dependent Claim
17 words
A method according to claim 21, wherein the weight ratio of gelatin to polyethylenimine is about 1:1.
Claim 26
Dependent Claim
26 words
A method according to claim 22, wherein the gelatin has a Bloom # of about 150 and the polyethylenimine has a molecular weight of about 50,000.
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) | 1991-08-30 | 1992-02-29 | 1992-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-30 | 1996-02-29 | 1996-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-30 | 2000-02-29 | 2000-08-30 | $7700.00 | Window Closed / Lapsed |