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US3905923A
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US
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Poly (urea-urethane) foams containing immobilized active enzymes
Assignee: 3M Co
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Filing: 1974-04-04
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Granted: 1975-09-16
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Expires: 1994-04-04
Abstract
Abstract An active, immobilized enzyme system is formed from an enzyme and a hydrophilic poly (urea-urethane) foam, said foam surrounding, entrapping and supporting the enzyme in an active configuration. The hydrophilic foam is formed by the reaction of water with a hydrophilic isocyanate-terminated polyoxyalkylene prepolymer containing at least 50 mole percent of oxyethylene in the prepolymer backbone.
Inventors
- 👤 James H Klug
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:41
CPC Classifications
C; C12; C12N; C12N11/00; C12N11/02; C12N11/04; Y; Y10; Y10S; Y10S521/00; Y10S521/905; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
73 words
AN ENZYME-CONTAINING FOAM COMPRISING: ABOUT 0.1 TO 15 PERCENT BY WEIGHT OF AN ACTIVE ENZYME PREPARATION ON AN ANHYDROUS SOLIDS BASIS, AND A HYDROPHILIC POLY(UREA-URETHANE) FOAM MATRIX HAVING AN OXYALKYLENE BACKBONE CONTAINING AT LEAST 50 MOLE PERCENT OXYETHYLENE, SAID HYDROPHILIC FOAM BEING FORMED BY REACTING AN ISOCYANATE-TERMINATED PREPOLYMER CONTAINING AN AQUEOUS SOLUTION OF SAID ENZYME WITH WATER, AND SAID HYDROPHILIC FOAM ENTRAPPING AND SUPPORTING SAID ENZYME IN AN ACTIVE CONFIGURATION FOR ENZYMATIC ACTIVITY.
Claim 2
Dependent Claim
73 words
AN ENZYME-CONTAINING FOAM COMPRISING: ABOUT 0.1 TO 15 PERCENT BY WEIGHT OF AN ACTIVE ENZYME PREPARATION ON AN ANHYDROUS SOLIDS BASIS, AND A HYDROPHILIC POLY(UREA-URETHANE) FOAM MATRIX HAVING AN OXYALKYLENE BACKBONE CONTAINING AT LEAST 50 MOLE PERCENT OXYETHYLENE, SAID HYDROPHILIC FOAM BEING FORMED BY REACTING AN ISOCYANATE-TERMINATED PREPOLYMER CONTAINING AN AQUEOUS SOLUTION OF SAID ENZYME WITH WATER, AND SAID HYDROPHILIC FOAM ENTRAPPING AND SUPPORTING SAID ENZYME IN AN ACTIVE CONFIGURATION FOR ENZYMATIC ACTIVITY.
Claim 3
Dependent Claim
53 words
A process for forming an active enzyme foam comprising the steps of: combining an aqueous solution of enzyme and a hydrophilic isocyanate-terminated polyoxyalkylene prepolymer, said prepolymer containing at least 50 mole percent oxyethylene units; and reacting the enzyme-containing isocyanate-terminated prepolymer with water to form a foam containing said enzyme in an active configuration.
Claim 4
Dependent Claim
53 words
A process for forming an active enzyme foam comprising the steps of: combining an aqueous solution of enzyme and a hydrophilic isocyanate-terminated polyoxyalkylene prepolymer, said prepolymer containing at least 50 mole percent oxyethylene units; and reacting the enzyme-containing isocyanate-terminated prepolymer with water to form a foam containing said enzyme in an active configuration.
Claim 5
Dependent Claim
16 words
The process according to claim 2, wherein said reaction is carried out at 0* to 3*C.
Claim 6
Dependent Claim
16 words
The enzyme foam of claim 1 containing from 1 to 50 percent by weight of filler.
Claim 7
Dependent Claim
19 words
The process according to claim 2 where said isocyanate-terminated prepolymer has a molecular weight from about 700 to 8500.
Claim 8
Dependent Claim
11 words
The enzyme foam of claim 1 containing a nonwoven reinforcing web.
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) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |