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US4356267A
Expired / Lapsed
US
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Enzyme immobilization in cellulosic hollow fibres
Assignee: Bellco SRL
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Filing: 1981-02-12
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Granted: 1982-10-26
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Expires: 2001-02-12
Abstract
Abstract Enzymes are immobilized in a bundle of cellulosic hollow fibres for use as a fibre-bundle dialyzer for purifying blood. Immobilization is carried out by circulating through the lumen of the fibres to activate the fibres an aqueous solution of sodium periodate at a concentration of 0.7-21 mg/ml, a circulation rate of 300-500 mm 3 /minute/mm 2 , a temperature of 15°-30° C. and for a period not exceeding 70 minutes, removing excess sodium periodate by washing the fibres, and directly or indirectly anchoring an enzyme to the activated fibres. Washing is preferably carried out by circulating through the lumen of the fibres dionized water followed by a dilute aqueous solution of glycerol. The fibres containing an immobilized enzyme may be sterilized with a sterilizing agent.
Inventors
- 👤 Lanfranco Callegaro
- 👤 Antonio Boniolo
- 👤 Ennio Denti
- 👤 Umberto Rosa
- 👤 Valdano Rossi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:59
CPC Classifications
B; B01; B01D; B01D63/00; B01D63/02; A; A61; A61M; A61M1/00; A61M1/36; A61M1/3679; C; C12; C12N; C12N11/00; C12N11/02; C12N11/10; C12N11/12; F; F16; F16L; F16L27/00; F16L27/02; F16L27/04
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
150 words
A method for immobilizing an enzyme in a bundle of cellulosic hollow fibres for a fibre-bundle dialyzer for purifying blood, comprising the following sequential steps: (a) activating said cellulosic hollow fibres by circulating through the lumen of the fibres in the bundle an aqueous solution of sodium periodate at a concentration of 0.7-2.1 mg/ml, at a circulation rate of 300-500 mm 3 /minute/mm 2 at a temperature of 15°-30° C. for a period of time not exceeding 70 minutes. (b) removing excess sodium periodate by circulating through the lumens of the fibres in the bundle deionized water to a total volume amounting to at least 10 times the total volume of the lumens of the fibres, and subsequently circulating a dilute aqueous solution of glycerol to the lumens of the fibres in the bundle; and (c) directly or indirectly anchoring the enzyme to the activated cellulosic fibres through covalent linkages.
Claim 2
Independent Claim
150 words
A method for immobilizing an enzyme in a bundle of cellulosic hollow fibres for a fibre-bundle dialyzer for purifying blood, comprising the following sequential steps: (a) activating said cellulosic hollow fibres by circulating through the lumen of the fibres in the bundle an aqueous solution of sodium periodate at a concentration of 0.7-2.1 mg/ml, at a circulation rate of 300-500 mm 3 /minute/mm 2 at a temperature of 15°-30° C. for a period of time not exceeding 70 minutes. (b) removing excess sodium periodate by circulating through the lumens of the fibres in the bundle deionized water to a total volume amounting to at least 10 times the total volume of the lumens of the fibres, and subsequently circulating a dilute aqueous solution of glycerol to the lumens of the fibres in the bundle; and (c) directly or indirectly anchoring the enzyme to the activated cellulosic fibres through covalent linkages.
Claim 3
Dependent Claim
14 words
Method according to claim 1, wherein the periodate concentration does not exceed 5 mg/ml.
Claim 4
Dependent Claim
12 words
Method according to claim 1, wherein the periodate concentration is 1 mg/ml.
Claim 5
Dependent Claim
16 words
Method according to claim 1, wherein the circulation rate is 350-480 mm 3 /min/mm 2 .
Claim 6
Dependent Claim
16 words
Method according to claim 4, wherein the circulation rate is 400 mm 3 /min/mm 2 .
Claim 7
Dependent Claim
23 words
Method according to claim 1, wherein the temperature is from 18° C. to 25° C. and the time period is of 60 minutes.
Claim 8
Dependent Claim
28 words
Method according to claim 1, wherein the lumen diameter of the fibres is from 200 to 300 microns and the wall thickness of the fibres is 10-20 microns.
Claim 9
Dependent Claim
12 words
Method according to claim 1, wherein the enzyme is a glutathione transferase.
Claim 10
Dependent Claim
10 words
Method according to claim 1, wherein the enzyme is creatininase.
Claim 11
Dependent Claim
10 words
Method according to claim 1, wherein the enzyme is asparaginase.
Claim 12
Dependent Claim
10 words
Method according to claim 1, wherein the enzyme is beta-galactoxydase.
Claim 13
Dependent Claim
10 words
Method according to claim 1, wherein the enzyme is uricase.
Claim 14
Dependent Claim
10 words
Method according to claim 1, wherein the enzyme is arginase.
Claim 15
Dependent Claim
19 words
Method according to claim 1, wherein the glycerol concentration in the said solution is from 8 to 15 vol.%.
Claim 16
Dependent Claim
15 words
Method according to claim 1, wherein the glycerol concentration in said solution is 10 vol.%.
Claim 17
Dependent Claim
37 words
Method according to claim 1, wherein the fibre bundle containing the immobilized enzyme is sterilized by exposing the fibres to an external sterilizing agent while the fibres are filled with a buffer solution specific to the enzyme.
Claim 18
Dependent Claim
23 words
Method according to claim 16, wherein the sterilization is effected by exposing the fibres to a gamma-radiation at a dosage of 2.5 Mrad.
Claim 19
Dependent Claim
24 words
Method according to claim 16, wherein the sterilization is effected by exposing the fibres to a gaseous mixture of ethylene oxide and a "Freon".
Claim 20
Dependent Claim
22 words
Method according to claim 18, wherein the gaseous mixture consists of 12 vol.% of ethylene oxide and 88 vol.% of "Freon" 12.
Claim 21
Dependent Claim
20 words
Method according to claims 16 or 17, wherein the buffer solution additionally comprises glycerol as protective agent for the fibres.
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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) | 1985-10-25 | 1986-04-26 | 1986-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-25 | 1990-04-26 | 1990-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-25 | 1994-04-26 | 1994-10-26 | $7700.00 | Window Closed / Lapsed |