Patent US4908572A successfully refreshed from Google Patents.
US4181609A
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Blood constituents testing method
Assignee: Individual
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Filing: 1978-11-13
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Granted: 1980-01-01
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Expires: 1998-11-13
Abstract
Abstract A method whereby separation of red cells from white cells in a centrifuged blood sample is improved. An effective amount of potassium oxalate is added to the blood sample to increase the density of the red cells. The blood sample is then warmed to minimize the increase in density of the white cells which otherwise occurs in certain cases.
Inventors
- 👤 Stephen C. Wardlaw
- 👤 James V. Massey, III
- 👤 Robert A. Levine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:46
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/491; A; A61; A61B; A61B5/00; A61B5/15; A61B5/150007; A61B5/150015; A61B5/150022; A61B5/150343
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
92 words
In a method for obtaining a clearly defined interface between the red cell layer and the white cell layer in a sample of anticoagulated blood which comprises the steps of adding a red cell densifying compound to said sample and subsequently centrifuging said sample, the improvement comprising the step of heating the blood sample prior to centrifugation thereof to a temperature in the range of about 41° C. to about 45° C. for an incubation period in the range of about three minutes to about ten minutes prior to said centrifuging step.
Claim 2
Dependent Claim
92 words
In a method for obtaining a clearly defined interface between the red cell layer and the white cell layer in a sample of anticoagulated blood which comprises the steps of adding a red cell densifying compound to said sample and subsequently centrifuging said sample, the improvement comprising the step of heating the blood sample prior to centrifugation thereof to a temperature in the range of about 41° C. to about 45° C. for an incubation period in the range of about three minutes to about ten minutes prior to said centrifuging step.
Claim 3
Dependent Claim
23 words
The method of claim 1, wherein said sample is heated to a temperature of 43° C. for an incubation period of five minutes.
References Cited (Backward Citations)
US2876769A
Cited
US3443060A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-12-31 | 1983-07-02 | 1984-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-31 | 1987-07-02 | 1988-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-31 | 1991-07-02 | 1992-01-01 | $7700.00 | Window Closed / Lapsed |