Patent US2302743A successfully refreshed from Google Patents.
US4489162A
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Fresh blood (unfixed) hematology control
Assignee: Baxter Healthcare Corp
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Filing: 1981-12-21
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Granted: 1984-12-18
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Expires: 2001-12-21
Abstract
Abstract Hematologic control and calibration standards are disclosed which are essentially plasma-free. These controls are prepared by the suspension of red blood cells in an appropriate buffer containing a stabilization effective amount of disaccharides, and other optional ingredients. Control and calibration standards prepared in the foregoing manner are suitable in the control and calibration of hematology analyzers for the following parameters: white cell count, red cell count, hemoglobin, hematocrit and the common derived parameters (i.e., mean cell volume, mean cell hemoglobin and mean cell hemoglobin concentration). The addition of platelets to the foregoing suspensions is also contemplated to provide a control for platelet parameters.
Inventors
- 👤 Pamela L. Hawkins
- 👤 Carole J. Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:04
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/96; G01N2333/00; G01N2333/435; G01N2333/76; G01N2333/765; G01N2400/00; G01N2400/10; G01N2400/12; G01N2400/14; G01N2400/22; G01N2496/00; G01N2496/05; Y; Y10; Y10T; Y10T436/00; Y10T436/10; Y10T436/101666; Y10T436/105831; Y10T436/107497; Y10T436/108331
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
132 words
A fluid comprising an essentially plasma and nutrient free hematologic control and calibration standard having a predetermined amount of washed and unfixed red blood cells in a low sodium buffered medium, a pH range of about 6.8 to about 8 and a stabilizer consisting essentially of about 5 to about 50 grams of a disaccharide per liter of buffered medium, the concentration of disaccharide and sodium ions relative to other unspecified components of the fluid being adjusted so as to (i) maintain the osmolality of the fluid in the range of from about 240 to about 310 mos/kg and (ii) preserve the native ionic concentration within the red blood cells, whereby an osmotic equilibrium across the red blood cell membrane is achieved thereby minimizing ionic transport across the red blood cell membrane.
Claim 2
Dependent Claim
132 words
A fluid comprising an essentially plasma and nutrient free hematologic control and calibration standard having a predetermined amount of washed and unfixed red blood cells in a low sodium buffered medium, a pH range of about 6.8 to about 8 and a stabilizer consisting essentially of about 5 to about 50 grams of a disaccharide per liter of buffered medium, the concentration of disaccharide and sodium ions relative to other unspecified components of the fluid being adjusted so as to (i) maintain the osmolality of the fluid in the range of from about 240 to about 310 mos/kg and (ii) preserve the native ionic concentration within the red blood cells, whereby an osmotic equilibrium across the red blood cell membrane is achieved thereby minimizing ionic transport across the red blood cell membrane.
Claim 3
Dependent Claim
24 words
The essentially plasma-free fluid suspension of claim 1, wherein the disaccharide is selected from the group consisting of lactose, sucrose, maltose and mixtures thereof.
Claim 4
Dependent Claim
25 words
An essentially plasma-free fluid suspension of claim 1, wherein the concentration of disaccharide is in the range of about 15 mM to about 145 mM.
Claim 5
Dependent Claim
27 words
The essentially plasma-free fluid suspension of claim 1, wherein the osmolality of the suspension is maintained within the range of from about 260 to about 300 mos/kg.
Claim 6
Dependent Claim
24 words
The essentially plasma-free fluid suspension of claim 1, containing serum albumin at a concentration in the range of about 2 to 8 grams/dl suspension.
Claim 7
Dependent Claim
39 words
The essentially plasma-free suspension of claim 1, containing a polysaccharide having a mean molecular weight in excess of 500,000 and being present in the suspension of the concentration in the range of from about 0.1 to about 1 gram/dl.
Claim 8
Dependent Claim
13 words
The essentially plasma-free fluid suspension of claim 6, wherein the polysaccharide is dextran.
Claim 9
Dependent Claim
24 words
The essentially plasma-free fluid suspension of claim 1, wherein the pH of suspension is in the range of from about 7.4 to about 7.5.
Claim 10
Dependent Claim
156 words
A fluid comprising a plasma and nutrient-free hematologic control and calibration standard having a predetermined amount of washed and unfixed red blood cells in a low sodium buffered medium, a pH range of about 6.8 to about 8.0 and a stabilizer consisting essentially of about 5 about 50 grams of a disaccharide per liter of buffered medium, the concentration of disaccharide and sodium ions relative to other unspecified components of this fluid being adjusted so as to (i) maintain the osmolality of the fluid in a range of from about 240 to about 340 mos/kg and (ii) to preserve the native ionic concentration within the red blood cells, thereby an osmotic equilibrium across the red blood cell membrane is achieved whereby minimizing an ionic transport across the red blood cell membrane, the pH of the fluid being maintained with the above range by a buffer selected from a group consisting of potassium phosphate and Good's buffers.
Claim 11
Dependent Claim
156 words
A fluid comprising a plasma and nutrient-free hematologic control and calibration standard having a predetermined amount of washed and unfixed red blood cells in a low sodium buffered medium, a pH range of about 6.8 to about 8.0 and a stabilizer consisting essentially of about 5 about 50 grams of a disaccharide per liter of buffered medium, the concentration of disaccharide and sodium ions relative to other unspecified components of this fluid being adjusted so as to (i) maintain the osmolality of the fluid in a range of from about 240 to about 340 mos/kg and (ii) to preserve the native ionic concentration within the red blood cells, thereby an osmotic equilibrium across the red blood cell membrane is achieved whereby minimizing an ionic transport across the red blood cell membrane, the pH of the fluid being maintained with the above range by a buffer selected from a group consisting of potassium phosphate and Good's buffers.
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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) | 1987-12-18 | 1988-06-18 | 1988-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-18 | 1992-06-18 | 1992-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-18 | 1996-06-18 | 1996-12-18 | $7700.00 | Window Closed / Lapsed |