Patent US4774093A successfully refreshed from Google Patents.
US4774093A
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Polysaccharide compositions, preparation and uses
Assignee: FMC Corp
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Filing: 1985-06-25
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Granted: 1988-09-27
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Expires: 2005-06-25
Abstract
Abstract Novel beta-1,3-glucan polysaccharide gels characterized by (a) coherent, uniform, non-particulate structure, and (b) substantially uniform pH throughout. The gels are prepared by dissolving a beta-1,3-glucan polysaccharide in an aqueous alkaline medium at a temperature of about 55° C. or below and while maintaining the solution at a temperature of at least 50° C., adjusting the pH to 10.5 or lower, followed by cooling below about 40° C. or heating above 50° C. The gels formed by cooling are reversible whereas the gels formed by heating are thermally irreversible. The gels are useful for supporting, separating, transforming or treating biological materials, as carriers for pharmaceuticals, as coatings for biological materials, in food products, and can be shaped to form disposable contact lenses.
Inventors
- 👤 Richard B. Provonchee
- 👤 Donald W. Renn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:57
CPC Classifications
C; C08; C08L; C08L5/00; A; A61; A61K; A61K47/00; A61K47/30; A61K47/36; A61K8/00; A61K8/18; A61K8/72; A61K8/73; A61Q; A61Q11/00; G; G02; G02B; G02B1/00; G02B1/04; G02B1/041; G02B1/043
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
18 words
A beta-1,3-glucan polysaccharide gel characterized by (a) coherent, uniform, non-particulate structure, and (b) a substantially uniform pH throughout.
Claim 2
Dependent Claim
18 words
A beta-1,3-glucan polysaccharide gel characterized by (a) coherent, uniform, non-particulate structure, and (b) a substantially uniform pH throughout.
Claim 3
Dependent Claim
11 words
The gel of claim 1 wherein the polysaccharide is biologically produced.
Claim 4
Dependent Claim
19 words
The gel of claim 1 wherein the polysaccharide is produced by a microorganism of the genus Alcaligenes or Agrobacterium.
Claim 5
Dependent Claim
17 words
The gel of claim 1 wherein the polysaccharide is produced by the microorganism Alcaligenes faecalis var. myxogenes.
Claim 6
Independent Claim
129 words
A method of preparing an aqueous polysaccharide solution capable upon cooling below about 40° C. of forming a reversible, high strength gel and capable upon being heated above about 50° C. of forming a thermally irreversible, high strength gel, said gel having a coherent, uniform, non-particulate structure and a substantially uniform pH throughout, which method comprises: (a) providing a beta-1,3-glucan polysaccharide normally insoluble in neutral aqueous medium but soluble in alkaline aqueous medium; (b) dissolving the polysaccharide in an aqueous alkaline medium at a temperature of about 55° C. or below to provide a solution thereof; and (c) while maintaining the solution at a temperature of at least 50° C. but lower than the decomposition temperature of the polysaccharide, adjusting the pH of the solution to 10.5 or lower.
Claim 7
Independent Claim
129 words
A method of preparing an aqueous polysaccharide solution capable upon cooling below about 40° C. of forming a reversible, high strength gel and capable upon being heated above about 50° C. of forming a thermally irreversible, high strength gel, said gel having a coherent, uniform, non-particulate structure and a substantially uniform pH throughout, which method comprises: (a) providing a beta-1,3-glucan polysaccharide normally insoluble in neutral aqueous medium but soluble in alkaline aqueous medium; (b) dissolving the polysaccharide in an aqueous alkaline medium at a temperature of about 55° C. or below to provide a solution thereof; and (c) while maintaining the solution at a temperature of at least 50° C. but lower than the decomposition temperature of the polysaccharide, adjusting the pH of the solution to 10.5 or lower.
Claim 8
Dependent Claim
11 words
The method of claim 5 wherein the polysaccharide is biologically produced.
Claim 9
Dependent Claim
19 words
The method of claim 5 wherein the polysaccharide is produced by a microorganism of the genus Alcaligenes or Agrobacterium.
Claim 10
Dependent Claim
17 words
The method of claim 5 wherein the polysaccharide is produced by the microorganism Alcaligenes faecalis var. myxogenes.
Claim 11
Dependent Claim
20 words
The method of claim 5 wherein the pH of the solution is adjusted by the addition of an organic acid.
Claim 12
Dependent Claim
12 words
The method of claim 9 wherein the organic acid is acetic acid.
Claim 13
Dependent Claim
17 words
The method of claim 5 wherein the solution is neutralized by the addition of a mineral acid.
Claim 14
Dependent Claim
12 words
The method of claim 11 wherein the mineral acid is phosphoric acid.
Claim 15
Dependent Claim
10 words
The polysaccharide solution prepared by the method of claim 5.
Claim 16
Dependent Claim
10 words
The polysaccharide solution prepared by the method of claim 6.
Claim 17
Dependent Claim
10 words
The polysaccharide solution prepared by the method of claim 7.
Claim 18
Dependent Claim
10 words
The polysaccharide solution prepared by the method of claim 8.
Claim 19
Dependent Claim
26 words
A method of preparing a reversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises cooling below about 40° C. the polysaccharide solution of claim 13.
Claim 20
Dependent Claim
26 words
A method of preparing a reversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises cooling below about 40° C. the polysaccharide solution of claim 14.
Claim 21
Dependent Claim
26 words
A method of preparing a reversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises cooling below about 40° C. the polysaccharide solution of claim 15.
Claim 22
Dependent Claim
26 words
A method of preparing a reversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises cooling below about 40° C. the polysaccharide solution of claim 16.
Claim 23
Dependent Claim
11 words
The reversible polysaccharide gel prepared by the method of claim 17.
Claim 24
Dependent Claim
11 words
The reversible polysaccharide gel prepared by the method of claim 18.
Claim 25
Dependent Claim
11 words
The reversible polysaccharide gel prepared by the method of claim 19.
Claim 26
Dependent Claim
11 words
The reversible polysaccharide gel prepared by the method of claim 20.
Claim 27
Dependent Claim
26 words
A method of preparing a thermally irreversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises heating above 50° C. the polysaccharide solution of claim 13.
Claim 28
Dependent Claim
26 words
A method of preparing a thermally irreversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises heating above 50° C. the polysaccharide solution of claim 14.
Claim 29
Dependent Claim
26 words
A method of preparing a thermally irreversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises heating about 50° C. the polysaccharide solution of claim 15.
Claim 30
Dependent Claim
26 words
A method of preparing a thermally irreversible, high strength gel of a beta-1,3-glucan polysaccharide, which comprises heating above 50° C. the polysaccharide solution of claim 16.
Claim 31
Dependent Claim
12 words
The thermally irreversible polysaccharide gel prepared by the method of claim 25.
Claim 32
Dependent Claim
12 words
The thermally irreversible polysaccharide gel prepared by the method of claim 26.
Claim 33
Dependent Claim
12 words
The thermally irreversible polysaccharide gel prepared by the method of claim 27.
Claim 34
Dependent Claim
12 words
The thermally irreversible polysaccharide gel prepared by the method of claim 28.
Claim 35
Dependent Claim
42 words
In a method for supporting, separating, transforming or treating biological materials wherein a biological material is incorporated into or placed in contact with a gel medium, the improvement which comprises utilizing as the gel medium the beta-1,3-glucan polysaccharide gel of claim 1.
Claim 36
Dependent Claim
42 words
In a method for supporting, separating, transforming or treating biological materials wherein a biological material is incorporated into or placed in contact with a gel medium, the improvement which comprises utilizing as the gel medium the beta-1,3-glucan polysaccharide gel of claim 17.
Claim 37
Dependent Claim
42 words
In a method for supporting, separating, transforming or treating biological materials wherein a biological material is incorporated into or placed in contact with a gel medium, the improvement which comprises utilizing as the gel medium the beta-1,3-glucan polysaccharide gel of claim 29.
Claim 38
Dependent Claim
63 words
In a method for preparing a gel medium containing a biological material wherein the biological material is incorporated into the gel by dispersing the biological material into a precursor gel-forming solution and thereafter gelling the resulting dispersion by cooling below about 40° C. or heating above about 50° C., the improvement which comprises utilizing as the gel-forming solution the solution of claim 5.
Claim 39
Dependent Claim
22 words
A biological product comprising a biological material and a carrier therefor, said carrier comprising a gel of claim 1 in particulate form.
Claim 40
Dependent Claim
18 words
A pharmaceutical composition comprising a drug and a carrier therefor, said carrier comprising a gel of claim 1.
Claim 41
Dependent Claim
12 words
A biological material having a coating of the gel of claim 1.
Claim 42
Dependent Claim
13 words
A disposable contact lens comprising a contact lens shaped gel of claim 1.
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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) | 1991-09-27 | 1992-03-28 | 1992-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-27 | 1996-03-28 | 1996-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-27 | 2000-03-28 | 2000-09-27 | $7700.00 | Window Closed / Lapsed |