Patent US2871749A successfully refreshed from Google Patents.
US4871671A
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US
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Immobilization of biological cells in polytetrafluoroethylene matrix
Assignee: 3M Co
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Filing: 1987-09-28
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Granted: 1989-10-03
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Expires: 2007-09-28
Abstract
Abstract Articles which are composite structure are prepared which comprise a fibrillated polytetrafluoroethylene (PTFE) matrix containing enmeshed and immobilized therein viable cells capable of their usual and continuous biochemical and biological performances. The viable cells cells can be animal, bacterial, fungal or yeast. Almost all cells entrapped within said matrix are separated from each other and are unbound within said matrix such that when said matrix is cut the cells of the cut edge are free to escape from the matrix.
Inventors
- 👤 Louis A. Errede
- 👤 George R. Hunt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:24
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/10; C02F3/105; C02F3/108; C12; C12M; C12M25/00; C12M25/14; C12M25/16; C12N; C12N1/00; C12N1/20; C12N1/205; C12N11/00; C12N11/02; C12N11/04; C12N11/08; C12N11/082; C12R; C12R2001/00; C12R2001/01; C12R2001/07; C12R2001/075; C12R2001/38; C12R2001/385; Y; Y02; Y02W; Y02W10/00; Y02W10/10
Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
95 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entraped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 2
Dependent Claim
95 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entraped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 3
Dependent Claim
19 words
The composite structure according to claim 1 wherein said viable cells range in size from 0.1 to 25 micrometers.
Claim 4
Dependent Claim
19 words
The composite structure according to claim 1 wherein said viable cells range in size from 0.3 to 15 micrometers.
Claim 5
Dependent Claim
13 words
The composite structure according to claim 1 wherein said viable cells are dried.
Claim 6
Dependent Claim
13 words
The composite structure according to claim 1 wherein said viable cells are hydrated.
Claim 7
Dependent Claim
12 words
The composite structure according to claim 1 wherein said composite is dried.
Claim 8
Dependent Claim
12 words
The composite structure according to claim 1 wherein said composite is hydrated.
Claim 9
Dependent Claim
17 words
The composite structure according to claim 1 wherein said viable cells are admixed with inert diluent particles.
Claim 10
Dependent Claim
46 words
The composite structure according to claim 8 wherein said inert diluent particles comprise in the range of greater than 0 up to 14.995 parts per part polytetrafluoroethylene, provided that said viable cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene.
Claim 11
Dependent Claim
30 words
The composite structure according to claim 1 wherein said viable cells have an absorptive capacity in the range of 2 to 20 grams of water per gram of dry cells.
Claim 12
Dependent Claim
16 words
The composite structure according to claim 1 having a tensile strength of at least 1.7 MPa.
Claim 13
Dependent Claim
22 words
The composite structure according to claim 1 wherein said polytetrafluoroethylene fibrils have a diameter in the range of 250 to 2500 Å.
Claim 14
Dependent Claim
25 words
The composite structure according to claim 1 wherein said structure is a sheet material having a thickness in the range of 0.1 to 10 mm.
Claim 15
Dependent Claim
17 words
The composite structure according to claim 1 where said viable cells are animal, bacterial, fungal or yeast.
Claim 16
Dependent Claim
43 words
The composite structure according to claim 1 wherein said viable cells are Achromobacter guttatus, Pseudomonas aeruginosa, Azotobacter agilis, Candida tropicalis, Clostridium butyricum, Escherichia coli, Micrococcus dentrificans, Pseudomonas mephitica var. lipolytica, Saccharomyces cerevisiae, Streptococcus faecalis, Tetrahymena pyriformis, Aspergillus niger, Bacillus thuringiensis, or mammalian cells.
Claim 17
Dependent Claim
12 words
The composite structure according to claim 1 further comprising a cell nutient.
Claim 18
Dependent Claim
29 words
The composite structure according to claim 1 further comprising a processing aid selected from the group consisting of calcuim carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
Claim 19
Dependent Claim
84 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluordethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable mammalian cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said fibril matrix and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 20
Dependent Claim
84 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluordethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable mammalian cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said fibril matrix and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 21
Dependent Claim
12 words
The composite structure according to claim 18 further comprising a cell nutrient.
Claim 22
Dependent Claim
29 words
The composite structure according to claim 18 further comprising a processing aid selected from the group consisting of calcium carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
Claim 23
Dependent Claim
17 words
The composite structure according to claim 18 wherein said viable cells are admixed with inert diluent particles.
Claim 24
Dependent Claim
98 words
A composite structure consisting essentially of: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 25
Dependent Claim
98 words
A composite structure consisting essentially of: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical and biological performances.
Claim 26
Dependent Claim
26 words
The composite structure according to claim 22 processing aid selected from the group consisting of calcium carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
Claim 27
Dependent Claim
141 words
A composite structure consisting essentially of: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, (b) 0.005 to 15 parts of viable cells part of polytetrafluoroethylene by weight entrapped within said micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical biological performances, and (c) greater than 0 and up to 14.995 parts by weight of inert diluent particles per part of polytetrafluoroethylene entrapped within the micropores of said matrix, provided that said vialbe cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene.
Claim 28
Dependent Claim
141 words
A composite structure consisting essentially of: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, (b) 0.005 to 15 parts of viable cells part of polytetrafluoroethylene by weight entrapped within said micropores of said matrix, such that almost all of said viable cells are separated from each other and are unbound within said matrix such that when said matrix is cut the cells at the cut edge are free to escape from said fibril matrix, said entrapped viable cells being capable of their usual and continuous biochemical biological performances, and (c) greater than 0 and up to 14.995 parts by weight of inert diluent particles per part of polytetrafluoroethylene entrapped within the micropores of said matrix, provided that said vialbe cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene.
Claim 29
Dependent Claim
31 words
The composite structure according to claim 24 wherein said diluent is a processing aid selected from the group consisting of calcium carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
Claim 30
Dependent Claim
202 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are capable of their usual and continuous biochemical and biological performances, said composite structure being prepared by a method comprising the steps of: (a) providing a blend consisting essentially of viable cells and surfactant and soap free polytetrafluoroethylene as an aqueous dispersion in the form of a damp paste; (b) adding sufficient water as a lubricant to exceed the absorptive capacity of the viable cells yet maintain a stiff dough consistency; (c) intensively mixing said stiff dough at a temperature in the range of 5° to 70° C. to fibrillate said polytetrafluoroethylene, and (d) biaxially calendering the resultant mass between calendering rolls at a temperature in the range of 5° to 70° C. and a pressure in the range of 1000 to 3000 MPa to cause further fibrillation of said polytetrafluoroethylene to provide said composite structure, said heating being controlled to preserve the viability of the cells.
Claim 31
Dependent Claim
202 words
A composite structure comprising: (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly distributed throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are capable of their usual and continuous biochemical and biological performances, said composite structure being prepared by a method comprising the steps of: (a) providing a blend consisting essentially of viable cells and surfactant and soap free polytetrafluoroethylene as an aqueous dispersion in the form of a damp paste; (b) adding sufficient water as a lubricant to exceed the absorptive capacity of the viable cells yet maintain a stiff dough consistency; (c) intensively mixing said stiff dough at a temperature in the range of 5° to 70° C. to fibrillate said polytetrafluoroethylene, and (d) biaxially calendering the resultant mass between calendering rolls at a temperature in the range of 5° to 70° C. and a pressure in the range of 1000 to 3000 MPa to cause further fibrillation of said polytetrafluoroethylene to provide said composite structure, said heating being controlled to preserve the viability of the cells.
Claim 32
Dependent Claim
19 words
The composite structure according to claim 26 wherein said viable cells range in size from 0.1 to 25 micrometers.
Claim 33
Dependent Claim
19 words
The composite structure according to claim 26 wherein said viable cells range in size from 0.3 to 15 micrometers.
Claim 34
Dependent Claim
13 words
The composite structure according to claim 26 wherein said viable cells are dried.
Claim 35
Dependent Claim
13 words
The composite structure according to claim 26 wherein said viable cells are hydrated.
Claim 36
Dependent Claim
17 words
The composite structure according to claim 26 wherein said viable cells are admixed with inert diluent particles.
Claim 37
Dependent Claim
46 words
The composite structure according to claim 31 wherein said inert diluent particles comprise in the range of greater than 0 up to 14.995 parts per part polytetrafluoroethylene, provided that said viable cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene.
Claim 38
Dependent Claim
43 words
The composite structure according to claim 26 wherein said viable cells are Achromobacter guttatus, Pseudomonas aeruginosa, Azotobacter agilis, Candida tropicalis, Clostridium butyricum, Escherichia coli, Micrococcus denitrificans, Pseudomonas mephitica var. lipolytica, Saccharomyces cerevisiae, Streptococcus faecalis, Tetrahymena pyriformis, Aspergillus niger, Bacillus thuringiensis or mammallan cells.
Claim 39
Dependent Claim
30 words
The composite structure according to claim 26 wherein said viable cells have an absorptive capacity in the range of 2 to 20 grams of water per gram of dry cells.
Claim 40
Dependent Claim
16 words
The composite structure according to claim 26 having a tensile strength of at least 1.7 MPa.
Claim 41
Dependent Claim
22 words
The composite structure according to claim 26 wherein said polytetrafluoroethylene fibrils have a diameter in the range of 250 to 2500 Å.
Claim 42
Dependent Claim
26 words
The composite structure according to claim 26 wherein said composite structure is a sheet material having a thickness in the range of 0.1 to 10 mm.
Claim 43
Dependent Claim
17 words
The composite structure according to claim 26 wherein said viable cells are animal, bacterial, fungal or yeast.
Claim 44
Dependent Claim
29 words
The composite structure according to claim 26 further comprising a processing aid selected from the group consisting of calcium carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
Claim 45
Dependent Claim
245 words
A composite structure consisting essentially of (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are capable of their usual and continuous biochemical and biological performances, and (c) greater than 0 up to 14.995 parts per part polytetrafluoroethylene of inert diluent particles admixed with said viable cells, provided that said viable cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene, said composite structure being prepared by a method comprising the steps of: (a) providing a blend consisting essentially of viable cells, diluent particles and surfactant and soap free polytetrafluoroethylene as an aqueous dispersion in the form of a damp paste; (b) adding sufficient water as a lubricant to exceed the absorptive capacity of the viable cells yet maintain a stiff dough consistency; (c) intensively mixing said stiff dough at a temperature in the range of 5° to 70° C. to fibrillate said polytetrafluoroethylene, and (d) biaxially calendering the resultant mass between calendering rolls at a temperature in the range of 5° to 70° C. and a pressure in the range of 1000 to 3000 MPa to cause further fibrillation of said polytetrafluoroethylene to provide said composite structure, said heating being controlled to preserve the viability of the cell.
Claim 46
Dependent Claim
245 words
A composite structure consisting essentially of (a) a surfactant and soap-free polytetrafluoroethylene fibril matrix containing micropores uniformly throughout said matrix, and (b) 0.005 to 15 parts of viable cells per part of polytetrafluoroethylene by weight entrapped within the micropores of said matrix, such that almost all of said viable cells are separated from each other and are capable of their usual and continuous biochemical and biological performances, and (c) greater than 0 up to 14.995 parts per part polytetrafluoroethylene of inert diluent particles admixed with said viable cells, provided that said viable cells plus diluent do not exceed 15 parts cells and diluent to 1 part polytetrafluoroethylene, said composite structure being prepared by a method comprising the steps of: (a) providing a blend consisting essentially of viable cells, diluent particles and surfactant and soap free polytetrafluoroethylene as an aqueous dispersion in the form of a damp paste; (b) adding sufficient water as a lubricant to exceed the absorptive capacity of the viable cells yet maintain a stiff dough consistency; (c) intensively mixing said stiff dough at a temperature in the range of 5° to 70° C. to fibrillate said polytetrafluoroethylene, and (d) biaxially calendering the resultant mass between calendering rolls at a temperature in the range of 5° to 70° C. and a pressure in the range of 1000 to 3000 MPa to cause further fibrillation of said polytetrafluoroethylene to provide said composite structure, said heating being controlled to preserve the viability of the cell.
Claim 47
Dependent Claim
31 words
The composite structure according to claim 40 wherein said diluent is a processing aid selected from the group consisting of calcium carbonate, starch, polyethylene, zeolite, chiten, Sephadex, cellulosics, vermiculite and clay.
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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) | 1992-10-02 | 1993-04-03 | 1993-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-02 | 1997-04-03 | 1997-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-02 | 2001-04-03 | 2001-10-03 | $7700.00 | Window Closed / Lapsed |