US4688387A
Expired / Lapsed
US
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Method for preservation and storage of viable biological materials at cryogenic temperatures
Assignee: Coleman Holdings Inc
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Filing: 1985-11-12
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Granted: 1987-08-25
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Expires: 2005-11-12
Abstract
Abstract A method for preserving biological material is disclosed in which the biological material is stored at cryogenic temperatures for long periods of time without incurring fatal damage to cells, tissues or organs. The process comprises freezing the biological material under conditions of temperature and pressure to avoid the formation of crystalline ice I at all times during the freezing process. Rather, metastable phases of ice are exploited to reduce damage to the biological material upon freezing, storage or subsequent thawing.
Inventors
- 👤 Robert M. Conaway
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:05
CPC Classifications
A; A01; A01N; A01N1/00; A01N1/10; A01N1/16; A01N1/165
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
153 words
A method of preserving and storing biological material comprising the steps of: (a) removing biological material from a donor organism and placing said material into a container capable of withstanding high pressures as applied in step (c) and capable of withstanding cryogenic temperatures as applied in step (d); and (b) introducing a substantially biologically inert liquid into said container in contact with said material in such manner as to substantially displace and expel from said container substantially all gases; and (c) pressurizing said container and said liquid to a pressure sufficient to prevent the formation of ice I upon subsequent cooling; and (d) cooling said container and its contents to a cryogenic temperature below approximately 173 deg. Kelvin; and (e) depressurizing said container and contents to normal atmospheric pressure while maintaining said cryogenic temperature, said depressurizing performed in such manner as to maintain in metastable state a phase other than crystalline ice I.
Claim 2
Independent Claim
153 words
A method of preserving and storing biological material comprising the steps of: (a) removing biological material from a donor organism and placing said material into a container capable of withstanding high pressures as applied in step (c) and capable of withstanding cryogenic temperatures as applied in step (d); and (b) introducing a substantially biologically inert liquid into said container in contact with said material in such manner as to substantially displace and expel from said container substantially all gases; and (c) pressurizing said container and said liquid to a pressure sufficient to prevent the formation of ice I upon subsequent cooling; and (d) cooling said container and its contents to a cryogenic temperature below approximately 173 deg. Kelvin; and (e) depressurizing said container and contents to normal atmospheric pressure while maintaining said cryogenic temperature, said depressurizing performed in such manner as to maintain in metastable state a phase other than crystalline ice I.
Claim 3
Dependent Claim
31 words
A method as in claim 1, further comprising the step, performed immediately following step (a) of claim 1, of: Perfusing said material with a solution containing at least one cryoprotective agent.
Claim 4
Dependent Claim
32 words
A method as in claim 2, wherein said pressurizing step (c) is to pressures sufficiently high to avoid the formation of ice III upon subsequent cooling, in excess of approximately 3,500 atmospheres.
Claim 5
Dependent Claim
17 words
A viable biological material preserved at cryogenic temperatures produced in accordance with the method of claim 3.
Claim 6
Dependent Claim
23 words
A method as in claim 3 wherein said pressurizing step (c) is performed sufficiently rapidly to avoid substantial damage to said biological material.
Claim 7
Dependent Claim
31 words
A method as in claim 2, wherein said pressurizing step (c) is to pressures sufficiently high to cause the substantial cessation of biological activity by vitrification of said cryoprotectant-perfused biological material.
Claim 8
Dependent Claim
24 words
A method as in claim 6 wherein said pressurizing step (c) is performed sufficiently rapidly to avoid substantial damage to said cryoprotectant-perfused biological material.
Claim 9
Dependent Claim
31 words
A method as in claim 2, wherein said pressurizing step (c) is to pressures sufficiently high to cause the substantial cessation of biological activity by vitrification of said cryoprotectant-perfused biological material.
Claim 10
Dependent Claim
82 words
A method of restoring the viability of a biological material stored in accordance with claim 2 comprising the steps of: (a) repressurizing said container and said liquid to a pressure sufficient to avoid the formation of crystalline ice I upon subsequent warming; and (b) raising the temperature of said container and contents to a temperature of at least 273 deg. Kelvin; and (c) depressurizing said container and contents to atmospheric pressure; and (d) flushing said cryoprotective agents out of said biological material.
Claim 11
Dependent Claim
36 words
A method as in claim 1 or claim 2 wherein said cryogenic temperature of step (d) is below approximately 123 deg. Kelvin obtained by means of immersion in a cryogenic liquid substantially similar to liquid nitrogen.
Claim 12
Dependent Claim
72 words
A method of restoring the viability of a biological material stored in accordance with claim 1 comprising the steps of: (a) repressurizing said container and said contents to a pressure sufficiently high to avoid the formation of crystalline ice I upon subsequent warming; and (b) raising the temperature of said container and contents to a temperature of at least 273 deg. Kelvin; and (c) depressurizing said container and contents to atmospheric pressure.
Claim 13
Dependent Claim
17 words
A viable biological material preserved at cryogenic temperatures produced in accordance with the method of claim 1.
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) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |