Patent US3715427A successfully refreshed from Google Patents.
US3715427A
Expired / Lapsed
US
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Stabilized erythrocytes and methods therefor
Assignee: Abbott Laboratories
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Filing: 1970-12-24
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Granted: 1973-02-06
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Expires: 1990-12-24
Abstract
Abstract A method for obtaining an improved, stabilized aldehyde-treated erythrocyte preparation having an increased hemagglutination titer. The erythrocytes are stabilized by sequential exposure to dilute solutions of pyruvic aldehyde and formaldehyde, subjected to a freeze-thaw cycle, and stored at a temperature of -20*C. or below.
Inventors
- 👤 A Hirata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:04
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/554; G01N33/555; G01N33/556; A; A01; A01N; A01N1/00; A01N1/10; A01N1/12; A01N1/128; Y; Y10; Y10T; Y10T436/00; Y10T436/10; Y10T436/101666; Y10T436/105831; Y10T436/107497; Y10T436/108331
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
145 words
A method for obtaining an improved, stabilized aldehyde-treated erythrocyte preparation which is useful in passive hemagglutination procedures, said method comprising the steps of: preparing a suspension of washed erythrocytes in a neutral buffered solution; treating said erythrocyte suspension with from 1.5 to 5.0 percent by volume of pyruvic aldehyde per volume of erythrocytes for from 12 to 24 hours at room temperature; washing the aldehyde-treated erythrocyte suspension with said buffered solution to remove the excess pyruvic aldehyde; treating the washed aldehyde-treated erythrocyte suspension with from 1.5 to 5.0 percent by volume of formaldehyde per volume of erythrocytes for from 12 to 24 hours; washing the resulting stabilized erythrocyte preparation with said buffered solution to remove the excess formaldehyde; cooling said erythrocyte preparation to about -190*C, increasing the temperature to about -20*C, and storing the resulting stabilized erythrocyte preparation at a temperature no greater than -20*C.
Claim 2
Independent Claim
145 words
A method for obtaining an improved, stabilized aldehyde-treated erythrocyte preparation which is useful in passive hemagglutination procedures, said method comprising the steps of: preparing a suspension of washed erythrocytes in a neutral buffered solution; treating said erythrocyte suspension with from 1.5 to 5.0 percent by volume of pyruvic aldehyde per volume of erythrocytes for from 12 to 24 hours at room temperature; washing the aldehyde-treated erythrocyte suspension with said buffered solution to remove the excess pyruvic aldehyde; treating the washed aldehyde-treated erythrocyte suspension with from 1.5 to 5.0 percent by volume of formaldehyde per volume of erythrocytes for from 12 to 24 hours; washing the resulting stabilized erythrocyte preparation with said buffered solution to remove the excess formaldehyde; cooling said erythrocyte preparation to about -190*C, increasing the temperature to about -20*C, and storing the resulting stabilized erythrocyte preparation at a temperature no greater than -20*C.
Claim 3
Dependent Claim
16 words
The method of claim 1 wherein said erythrocyte preparation is cooled to -190*C. in liquid nitrogen.
Claim 4
Dependent Claim
50 words
The method of claim 1 wherein the temperature of the erythrocyte preparation is maintained at a temperature of about -20*C. for about 6 days, raised to a temperature of about 24*C. for 2-4 hours, recooled to about -190*C. and then returned to and stored at a temperature of about -20*C.
Claim 5
Dependent Claim
16 words
The method of claim 3 wherein the freeze-thaw cycle is repeated from six to nine times.
Claim 6
Dependent Claim
49 words
A method of potentiating the stabilized erythrocytes obtained by the process of claim 1 by treating the erythrocyte preparation with a dilute solution of a suitable oxidizing agent at a temperature of from 20* to 30*C. for from 10 to 20 minutes and washing the potentiated stabilized erythrocyte preparation.
Claim 7
Dependent Claim
36 words
The process of claim 5 wherein said erythrocyte preparation is treated at 24*C. for 15 minutes with a 0.00035 M sodium periodate solution and then washed with a phosphate buffered solution to remove the oxidizing agent.
Claim 8
Dependent Claim
16 words
The method of claim 6 wherein said neutral buffering solution is a pH 7.0-7.2 phosphate solution.
Claim 9
Dependent Claim
11 words
The stable erythrocyte preparation obtained by the method of claim 1.
References Cited (Backward Citations)
US3057775A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |