US4255256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Medium for the separation of human blood leucocytes
Assignee: Individual
•
Filing: 1979-11-23
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Granted: 1981-03-10
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Expires: 1999-11-23
Abstract
Abstract A rapid one-step density separation method for separating and purifying whole blood into mononuclear and polymorphonuclear leucocyte and erythrocyte fractions wherein use is made of a separating medium consisting of a single aqueous solution of a high molecular weight sucrose or glucose polymer, and a water soluble metrizoate or diatrizoate compound, the density of the solution being greater than 1.095 gm/ml at room temperature and the concentration of the sucrose or glucose polymer lying in the range of 5 to 10% (based on weight/total volume of solution).
Inventors
- 👤 Antonio Ferrante
- 👤 Yee H. Thong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:29
CPC Classifications
B; B01; B01D; B01D43/00; G; G01; G01N; G01N33/00; G01N33/48
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
152 words
A rapid one step method of density separation of whole blood into (i) mononuclear leucocyte (ii) polymorphonuclear leucocyte and (iii) erythrocyte fractions wherein a whole blood sample is layered onto an aqueous separating medium in a centrifuge tube and the blood sample and separating medium centrifuged so that the whole blood sample is fractionalised into the fractions hereinabove, wherein the separating medium consists of a mixture of (a) an aqueous solution of an erythrocyte aggregating or clumping agent being a high molecular weight sucrose or glucose polymer and (b) a solution of a water soluble metrizoate- or diatrizoate- compound of relatively high density and relatively low viscosity and osmolarity, wherein (i) the density of the solution mixture (a) and (b) is greater than 1.095 gm/ml at room temperature, and (ii) the concentration of (a) lies in the range of 5 to 11% (based on the weight per total volume of solution mixture).
Claim 2
Dependent Claim
152 words
A rapid one step method of density separation of whole blood into (i) mononuclear leucocyte (ii) polymorphonuclear leucocyte and (iii) erythrocyte fractions wherein a whole blood sample is layered onto an aqueous separating medium in a centrifuge tube and the blood sample and separating medium centrifuged so that the whole blood sample is fractionalised into the fractions hereinabove, wherein the separating medium consists of a mixture of (a) an aqueous solution of an erythrocyte aggregating or clumping agent being a high molecular weight sucrose or glucose polymer and (b) a solution of a water soluble metrizoate- or diatrizoate- compound of relatively high density and relatively low viscosity and osmolarity, wherein (i) the density of the solution mixture (a) and (b) is greater than 1.095 gm/ml at room temperature, and (ii) the concentration of (a) lies in the range of 5 to 11% (based on the weight per total volume of solution mixture).
Claim 3
Dependent Claim
36 words
A rapid one step method according to claim 1 wherein (a) is a sucrose polymer and the concentration of said sucrose polymer lies in the range of 7 to 11% (based on weight/total volume of solution).
Claim 4
Dependent Claim
25 words
A rapid one step method according to claim 2 wherein the sucrose polymer is Ficoll (Registered Trade Mark) having a molecular weight of approximate 400,000.
Claim 5
Dependent Claim
29 words
A method according to claim 1 wherein (a) is a glucose polymer, the concentration thereof being in the range of 5 to 9% (based on weight/total volume of solution).
Claim 6
Dependent Claim
22 words
A method according to claim 4 wherein said glucose polymer is Dextran (Registered Trade Mark) having a molecular weight of approximately 264,000.
Claim 7
Dependent Claim
31 words
A method according to claim 2 wherein (b) is a mixture of an aqueous solution of meglumine diatrizoate or meglumine metrizoate and an aqueous solution of sodium metrizoate or sodium diatrizoate.
Claim 8
Dependent Claim
57 words
A method according to claim 1 wherein the separating medium is an aqueous solution of Ficoll (Registered Trade Mark) having a concentration of between 7 and 11% (based on weight/total volume of solution), and Hypaque 85% (Registered Trade Mark), wherein the density of the solution is in the range of 1.095 to 1.20 gm/ml at room temperature.
Claim 9
Dependent Claim
18 words
A method according to claim 1 wherein the density of the solution is 1.114 gm/ml at room temperature.
References Cited (Backward Citations)
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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) | 1984-03-09 | 1984-09-08 | 1985-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-09 | 1988-09-08 | 1989-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-09 | 1992-09-08 | 1993-03-10 | $7700.00 | Window Closed / Lapsed |