US3998946A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fibrinogen-free plasminogen-plasmin-free plasma and method of preparing and using same
Assignee: University of Minnesota System
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Filing: 1975-04-23
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Granted: 1976-12-21
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Expires: 1995-04-23
Abstract
Abstract A method of treating blood plasma or fractionated plasma products with fumed colloidal silica to remove fibrinogen without polymerization to fibrin, to remove the plasminogen-plasmin proteolytic enzyme system, to remove cholesterol and lipoproteins and reduce triglycerides, while maintaining plasma coagulation factor II at pretreatment levels and leaving immunoglobulins and other protein constitutents unaffected, and the resulting product. Plasma products treated with fumed silica may be subjected to long-term storage for a year or more without loss of its biologically active support properties, thereby circumventing the problem of hepatitis. The treated plasma products, either fresh or after long-term storage, may be used as a perfusion support media for organ perfusion, for treatment of hemmorrhagic shock and similar purposes for which untreated plasma and fractionated plasma products are customarily used, with equal or superior effectiveness.
Inventors
- 👤 Richard M. Condie
- 👤 Luis H. Toledo-Pereyra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:03
CPC Classifications
A; A61; A61K; A61K35/00; A61K35/12; A61K35/14; A61K35/16
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
85 words
The method of treatment to remove fibrinogen without polymerization to fibrin, to remove the plasminogen-plasmin enzyme system, and to remove lipoproteins and lipids from blood plasma and plasma fractions containing the same, which method comprises: A. intimately admixing finely divided sterile fumed silica containing siloxan and silanol groups at its surface with a blood plasma product selected from the class consisting of blood plasma and plasma fractionation products, and B. separating the silica and associated fibrinogen, plasminogen-plasmin, lipoprotein and lipids from the remaining plasma product.
Claim 2
Independent Claim
85 words
The method of treatment to remove fibrinogen without polymerization to fibrin, to remove the plasminogen-plasmin enzyme system, and to remove lipoproteins and lipids from blood plasma and plasma fractions containing the same, which method comprises: A. intimately admixing finely divided sterile fumed silica containing siloxan and silanol groups at its surface with a blood plasma product selected from the class consisting of blood plasma and plasma fractionation products, and B. separating the silica and associated fibrinogen, plasminogen-plasmin, lipoprotein and lipids from the remaining plasma product.
Claim 3
Dependent Claim
31 words
The method according to claim 1 further characterized in that silica is added to plasma in the proportion of about 10 to 50 grams of silica per liter of plasma product.
Claim 4
Dependent Claim
32 words
The method according to claim 1 further characterized in that said silica is admixed at a temperature between about 4° to 37° C and stirred for about 20 minutes to 2 hours.
Claim 5
Dependent Claim
18 words
The method according to claim 1 further characterized in that said silica is admixed in the dry state.
Claim 6
Dependent Claim
33 words
The method according to claim 1 further characterized in that said silica is admixed in suspension in normal saline solution in the proportion of about one gram silica per 15 milliliters of saline.
Claim 7
Dependent Claim
16 words
The method according to claim 1 further characterized in that said silica is separated by centrifugation.
Claim 8
Dependent Claim
16 words
The method according to claim 1 further characterized in that said silica is separated by filtration.
Claim 9
Dependent Claim
37 words
The method according to claim 6 further characterized in that said silica is separated by centrifugation at about 100 to 10000 rpm for about 10 to 30 minutes at a temperature between about 0° and 37° C.
Claim 10
Dependent Claim
13 words
A fibrinogen-free plasminogen-plasmin-free blood plasma product produced by the method of claim 1.
Claim 11
Dependent Claim
44 words
In the method of perfusing kidneys removed by nephrectomy to preserve the same pending transplantation into a living body, the improvement which consists in using as a perfusate a fumed silica treated fibrinogen-free, plasminogen-plasmin-free blood plasma product produced by the method of claim 1.
Claim 12
Dependent Claim
38 words
In the method of treating hypovolemic (hemorrhagic) and endotoxic shock in living bodies, the improvement which consists in transfusing the body with a fumed silica treated fibrinogen-free, plasminogen-plasmin-free blood plasma product produced by the method of claim 1.
Claim 13
Independent Claim
133 words
The method of treatment to remove fibrinogen without polymerization to fibrin and without liberation of fibrinogen split products, to remove the plasminogen-plasmin enzyme system, and to remove lipoproteins and lipids from blood plasma and plasma fractions containing the same, which method comprises: A. introducing sterile finely divided fumed silica containing siloxan and silanol groups on its surface into a blood plasma product selected from the class consisting of blood plasma and plasma fractionation products with stirring to a concentration between about 10 and 50 grams of said silica per liter of plasma product, B. continuing agitation at a temperature between about 4° to 37° C for about 20 minutes to 2 hours, and C. treating the mixture to separate the silica and associated fibrinogen, plasminogen-plasmin, lipoproteins and lipids from the remaining plasma product.
Claim 14
Independent Claim
133 words
The method of treatment to remove fibrinogen without polymerization to fibrin and without liberation of fibrinogen split products, to remove the plasminogen-plasmin enzyme system, and to remove lipoproteins and lipids from blood plasma and plasma fractions containing the same, which method comprises: A. introducing sterile finely divided fumed silica containing siloxan and silanol groups on its surface into a blood plasma product selected from the class consisting of blood plasma and plasma fractionation products with stirring to a concentration between about 10 and 50 grams of said silica per liter of plasma product, B. continuing agitation at a temperature between about 4° to 37° C for about 20 minutes to 2 hours, and C. treating the mixture to separate the silica and associated fibrinogen, plasminogen-plasmin, lipoproteins and lipids from the remaining plasma product.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-12-21 | 1980-06-21 | 1980-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-21 | 1984-06-21 | 1984-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-21 | 1988-06-21 | 1988-12-21 | $7700.00 | Window Closed / Lapsed |