Patent US4764463A successfully refreshed from Google Patents.
US4764463A
Expired / Lapsed
US
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Platelet cyropreservation
Assignee: University of Tennessee Research Foundation
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Filing: 1986-10-30
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Granted: 1988-08-16
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Expires: 2006-10-30
Abstract
Abstract A method for preserving blood platelets by freezing the platelets in contact with a cryoprotectant solution containing a sufficient quantity of prostacyclin for the substantially complete inhibition of platelet function and having a pH which promotes the preservation of the platelets.
Inventors
- 👤 James M. Mason
- 👤 David D. Pifer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:13
CPC Classifications
A; A61; A61K; A61K35/00; A61K35/12; A61K35/14; A61K35/19; A01; A01N; A01N1/00; A01N1/10; A01N1/12; A01N1/122; A01N1/125
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
63 words
A method for platelet cryopreservation comprising freezing platelets in contact with an aqueous saline cryoprotectant solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% by weight glucose and containing sufficient prostacyclin to substantially completely inhibit platelet function throughout the freezing process, said cryoprotectant solution having a pH of between about 7.2 and about 7.6.
Claim 2
Independent Claim
63 words
A method for platelet cryopreservation comprising freezing platelets in contact with an aqueous saline cryoprotectant solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% by weight glucose and containing sufficient prostacyclin to substantially completely inhibit platelet function throughout the freezing process, said cryoprotectant solution having a pH of between about 7.2 and about 7.6.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein prostacyclin is present in the cryoprotectant solution at a minimum level necessary to achieve substantially complete inhibition of platelet function throughout the freezing process.
Claim 4
Dependent Claim
21 words
The method of claim 1 wherein said freezing is performed at a rate of at least about -20° C. per minute.
Claim 5
Independent Claim
68 words
A method of producing and cryopreserving a platelet concentrate comprising: producing a platelet concentrate by concentrating platelet rich plasma in the presence of sufficient prostacyclin to substantially completely inhibit platelet function; and freezing said platelet concentrate in contact with a cryoprotectant solution containing sufficient prostacyclin to substantially completely inhibit platelet function throughout the freezing process, said cryoprotectant solution having a pH of between about 7.0 and about 8.0.
Claim 6
Independent Claim
68 words
A method of producing and cryopreserving a platelet concentrate comprising: producing a platelet concentrate by concentrating platelet rich plasma in the presence of sufficient prostacyclin to substantially completely inhibit platelet function; and freezing said platelet concentrate in contact with a cryoprotectant solution containing sufficient prostacyclin to substantially completely inhibit platelet function throughout the freezing process, said cryoprotectant solution having a pH of between about 7.0 and about 8.0.
Claim 7
Dependent Claim
19 words
The method of claim 4 wherein the pH of the cryoprotectant solution is between about 7.2 and about 7.6.
Claim 8
Dependent Claim
34 words
The method of claim 4 wherein said cryoprotectant solution is an aqueous saline solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% by weight glucose.
Claim 9
Dependent Claim
30 words
The method of claim 4 wherein prostacyclin is present in the cryoprotectant solution at a minimum level necessary to achieve substantially complete inhibition of platelet function throughout the freezing process.
Claim 10
Dependent Claim
21 words
The method of claim 4 wherein said freezing is performed at a rate of at least about -20° C. per minute.
Claim 11
Dependent Claim
53 words
The method of claim 4 wherein said concentrating of the platelet rich plasma in the presence sufficient prostacyclin to produce a platelet concentrate is performed by adding said prostacyclin to the platelet rich plasma and centrifuging to separate platelets from a supernatant plasma followed by removing at least some of the supernatant plasma.
Claim 12
Dependent Claim
63 words
The method of claim 4 wherein said step of concentrating the platelet rich plasma in the presence of prostacyclin to produce said platelet concentrate comprises adding said prostacyclin to the platelet rich plasma, centrifuging to separate platelets from a supernatant plasma, removing at least some of the supernatant plasma, and resuspending in a portion of said supernatant plasma to produce said platelet concentrate.
Claim 13
Dependent Claim
60 words
The method of claim 10 further comprising the following steps prior to the freezing of the platelets in contact with a cryoprotectant solution: adding the prostacyclin to be present during freezing to the platelet concentrate; adding a concentrate solution containing the constituents of the cryoprotectant solution and a pH buffer to the prostacyclin-containing platelet concentrate to produce the cryoprotectant solution.
Claim 14
Dependent Claim
37 words
The method of claim 11 wherein said concentrated solution contains sufficient glycerol and glucose to produce a cryoprotectant solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% glucose.
Claim 15
Dependent Claim
29 words
The method of claim 11 wherein said concentrated solution contains sufficient sodium citrate to result in a cryoprotectant solution having a pH of between about 7.2 and about 7.6.
Claim 16
Dependent Claim
65 words
A frozen platelet preparation for use upon thawing prepared by freezing platelets in the presence of an aqueous saline cryoprotectant solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% by weight glucose and containing sufficient prostacyclin to substantially inhibit platelet function throughout the freezing process and having a pH of between about 7.2 and about 7.6.
Claim 17
Dependent Claim
65 words
A frozen platelet preparation for use upon thawing prepared by freezing platelets in the presence of an aqueous saline cryoprotectant solution containing between about 4% and about 7% by weight glycerol and between about 2% and about 6% by weight glucose and containing sufficient prostacyclin to substantially inhibit platelet function throughout the freezing process and having a pH of between about 7.2 and about 7.6.
References Cited (Backward Citations)
US3296091A
Cited
US3629071A
Cited
US3729947A
Cited
US3996103A
Cited
US4033816A
Cited
US4110161A
Cited
US4059967A
Cited
US4251995A
Cited
US4365629A
Cited
US4303671A
Cited
US4558142A
Cited
US4390619A
Cited
US4476221A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-08-16 | 1992-02-15 | 1992-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-16 | 1996-02-15 | 1996-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-16 | 2000-02-15 | 2000-08-16 | $7700.00 | Window Closed / Lapsed |