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US4521518A
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Multi-purpose blood diluent and lysing agent for differential determination of lymphoid-myeloid population of leukocytes
Assignee: Coulter Corp
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Filing: 1982-07-06
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Granted: 1985-06-04
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Expires: 2002-07-06
Abstract
Abstract An isotonic multipurpose blood diluent, and a method for use of this diluent with a weak lysing reagent system which is especially suitable for routine enumeration of traditional hemogram values, and also the determination of lymphoid-myeloid populations of leukocytes, particularly in automatic particle counting systems. This blood diluent is capable of affording accurate, reproducible test results. It is an osmotically balanced aqueous solution of preselected pH containing Procaine hydrochloride for maintaining erythrocyte morphology during operation, N-(2-acetamido)iminodiacetic acid (ADA) as a blood cell stabilizing agent, and bacteriostatic agents including sodium 1-hydroxypyridine-2-thione, and dimethylolurea which, together with the ADA, allow preferential determination of myeloid-lymphoid leukocytes, and other hematological values. The lysing agent is a mixture of an aqueous solution of at least one quaternary ammonium salt having surface active properties, and an alkali metal cyanide.
Inventors
- 👤 James H. Carter
- 👤 Stephen L. Ledis
- 👤 Harold R. Crews
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:12
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/10; G01N15/1031; G01N15/12; G01N15/131; G01N33/00; G01N33/48; G01N33/50; G01N33/5005; G01N33/5094; Y; Y10; Y10T; Y10T436/00; Y10T436/10; Y10T436/101666; Y10T436/105831; Y10T436/106664; Y10T436/107497; Y10T436/108331
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
66 words
A multi-purpose isotonic blood diluent comprising a cell stabilizing mixture of: 1. N-(2-acetamido)iminodiacetic acid, 2. Procaine hydrochloride, 3. at least one cell membrane stabilizer selected from the group consisting of: dimethylolurea, hexamethylenetetramine, and N-hydroxymethylacetamide, 4. at least one germicide selected from the group consisting of: chlorhexidene diacetate, dimethylolurea, and sodium 1-hydroxypyridine-2-thione, and 5. sodium sulfate and sodium chloride, in an osmotically balanced and substantially neutral solution.
Claim 2
Dependent Claim
66 words
A multi-purpose isotonic blood diluent comprising a cell stabilizing mixture of: 1. N-(2-acetamido)iminodiacetic acid, 2. Procaine hydrochloride, 3. at least one cell membrane stabilizer selected from the group consisting of: dimethylolurea, hexamethylenetetramine, and N-hydroxymethylacetamide, 4. at least one germicide selected from the group consisting of: chlorhexidene diacetate, dimethylolurea, and sodium 1-hydroxypyridine-2-thione, and 5. sodium sulfate and sodium chloride, in an osmotically balanced and substantially neutral solution.
Claim 3
Independent Claim
45 words
A method which comprises the steps of: I. treating a blood sample with an isotonic diluent comprising a cell stabilizing mixture of: 1. N-(2-acetamido)iminodiacetic acid, 2. Procaine hydrochloride, 3. at least one cell membrane stabilizer selected from the group consisting of: dimethylolurea, hexamethylenetetramine, and N-hydroxymethylacetamide,
Claim 4
Independent Claim
45 words
A method which comprises the steps of: I. treating a blood sample with an isotonic diluent comprising a cell stabilizing mixture of: 1. N-(2-acetamido)iminodiacetic acid, 2. Procaine hydrochloride, 3. at least one cell membrane stabilizer selected from the group consisting of: dimethylolurea, hexamethylenetetramine, and N-hydroxymethylacetamide,
Claim 5
Dependent Claim
100 words
at least one germicide selected from the group consisting of: chlorhexidene diacetate, dimethylolurea, and sodium 1-hydroxypyridine-2-thione, and 5. sodium sulfate and sodium chloride, in an osmotically balanced and substantially neutral solution, and then II. lysing with a reagent comprising a mixture of an aqueous solution of at least one quaternary ammonium salt detergent and an alkali metal cyanide, said quaternary ammonium salt and said alkali metal cyanide being present in a concentration range which is effective to give a differential determination of lymphoid and myeloid populations of leukocytes followed by determination of hemogram values, particularly in automatic particle counting systems.
Claim 6
Dependent Claim
100 words
at least one germicide selected from the group consisting of: chlorhexidene diacetate, dimethylolurea, and sodium 1-hydroxypyridine-2-thione, and 5. sodium sulfate and sodium chloride, in an osmotically balanced and substantially neutral solution, and then II. lysing with a reagent comprising a mixture of an aqueous solution of at least one quaternary ammonium salt detergent and an alkali metal cyanide, said quaternary ammonium salt and said alkali metal cyanide being present in a concentration range which is effective to give a differential determination of lymphoid and myeloid populations of leukocytes followed by determination of hemogram values, particularly in automatic particle counting systems.
Claim 7
Dependent Claim
18 words
The isotonic diluent of claim 1 wherein the cell membrane stabilizer is dimethylolurea and the germicide is dimethylolurea.
Claim 8
Dependent Claim
18 words
The isotonic diluent of claim 1 wherein the concentration of said Procaine hydrochloride is 75 to 250 mg/L.
Claim 9
Dependent Claim
18 words
The isotonic diluent of claim 1 wherein the concentration of said N-(2-acetamido)iminodiacetic acid is 1.2 to 2.0 g/L.
Claim 10
Dependent Claim
95 words
The method of claim 2 wherein said lysing agent in step II comprises one or more quaternary ammonium salt detergents selected from the group consisting of compounds having the formula: ##STR2## where R 1 is a long chain alkyl radical having 10 to 18 carbons atoms, and R 2 , R 3 and R 4 are short chain alkyl radicals having1 to 6 carbon atoms, and X - is a salt forming radical selected from the group consisting of Cl, Br, I, PO 4 and CH 3 SO 4 , and an alkali metal cyanide.
Claim 11
Dependent Claim
14 words
The method of claim 2 wherein said quaternary ammonium salt detergent is hexadecyltrimethylammonium chloride.
Claim 12
Dependent Claim
14 words
The method of claim 2 wherein said quaternary ammonium salt detergent is hexadecyltrimethylammonium bromide.
Claim 13
Dependent Claim
14 words
The method of claim 2 wherein said quaternary ammonium salt detergent is dodecyltrimethylammonium chloride.
Claim 14
Dependent Claim
14 words
The method of claim 2 wherein said quaternary ammonium salt detergent is tetradecyltrimethylammonium bromide.
Claim 15
Dependent Claim
14 words
The method of claim 2 wherein said quaternary ammonium salt detergent is cetyldimethylethylammonium bromide.
Claim 16
Dependent Claim
43 words
The method of claim 2 wherein said quaternary ammonium salt detergent is a mixture of 40 to 70 g/L of dodecyltrimethylammonium chloride (50% solution) and 4 to 7 g/L of tetradecyltrimethylammonium bromide, and said alkali metal cyanide is 250-500 mg/L of potassium cyanide.
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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) | 1988-06-03 | 1988-12-03 | 1989-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-03 | 1992-12-03 | 1993-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-03 | 1996-12-03 | 1997-06-04 | $7700.00 | Window Closed / Lapsed |