US3987159A
Expired / Lapsed
US
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Stable sensitized erythrocytes and preparation means
Assignee: Bayer Pharma AG
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Filing: 1974-03-01
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Granted: 1976-10-19
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Expires: 1994-03-01
Abstract
Abstract Stable preparations of sensitized erythrocytes are provided by simultaneously admixing washed erythrocytes in a buffered aqueous solution of glutaraldehyde, antigen or antigen-protein conjugate and formaldehyde. After washing, the separated sensitized erythrocytes can be lyophilized and thereby become stable at room temperature.
Inventors
- 👤 Jurgen Spona
- 👤 Michael Topert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:03
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/554; G01N33/555; Y; Y10; Y10S; Y10S436/00; Y10S436/811; Y10S436/814; Y10S436/815; Y10S436/817; Y10S436/818; Y10S436/826
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
143 words
In a process for the preparation of sensitized, antigen-coated erythrocytes suitable for use in immunochemical hemagglutination diagnostic techniques by admixing a reaction mixture containing a suspension of washed erythrocytes in an aqueous solution containing an erythrocyte-sensitizing amount of an antigen or antigen-carrier protein conjugate and a coupling amount of glutaraldehyde under erythrocyte-sensitizing incubation conditions for a period of time sufficient to form erythrocytes sensitized by the coupling thereto of said antigen or antigen-carrier protein conjugate thereof, the improvement comprising simultaneously reacting said admixture with an erythrocyte-hardening amount of formaldehyde at a temperature of about 5°-45° C. for about 1-12 hours while maintaining the pH of the resultant admixture at 5.5-8.5 to form sensitized, antigen-coated erythrocytes capable of being lyophilized to form a preparation exhibiting 95-100% of the hemagglutination activity of the fresh preparation and which is stable for 6-12 months at room temperature.
Claim 2
Dependent Claim
143 words
In a process for the preparation of sensitized, antigen-coated erythrocytes suitable for use in immunochemical hemagglutination diagnostic techniques by admixing a reaction mixture containing a suspension of washed erythrocytes in an aqueous solution containing an erythrocyte-sensitizing amount of an antigen or antigen-carrier protein conjugate and a coupling amount of glutaraldehyde under erythrocyte-sensitizing incubation conditions for a period of time sufficient to form erythrocytes sensitized by the coupling thereto of said antigen or antigen-carrier protein conjugate thereof, the improvement comprising simultaneously reacting said admixture with an erythrocyte-hardening amount of formaldehyde at a temperature of about 5°-45° C. for about 1-12 hours while maintaining the pH of the resultant admixture at 5.5-8.5 to form sensitized, antigen-coated erythrocytes capable of being lyophilized to form a preparation exhibiting 95-100% of the hemagglutination activity of the fresh preparation and which is stable for 6-12 months at room temperature.
Claim 3
Dependent Claim
17 words
The process of claim 1, wherein said aqueous solution is buffered to a pH of about 7.0-7.2.
Claim 4
Dependent Claim
12 words
The process of claim 1, wherein said temperature is about 37° C.
Claim 5
Dependent Claim
20 words
The process of claim 2, wherein said temperature is about 37° C. and the incubation time is about 4 hours.
Claim 6
Dependent Claim
14 words
The process of claim 1, wherein said antigen is a hormone or an enzyme.
Claim 7
Dependent Claim
11 words
The process of claim 5, wherein said antigen is a proteohormone.
Claim 8
Dependent Claim
16 words
The process of claim 6, wherein said proteohormone is human chorionic gonadotropin or human placenta lactogen.
Claim 9
Dependent Claim
22 words
The process of claim 1, wherein 4-12% washed erythrocytes; 0.2-2% glutaraldehyde; 0.6-6% formaldehyde; and 0.01-0.25% antigen or antigen-carrier protein conjugate are admixed.
Claim 10
Dependent Claim
11 words
The process of claim 1, further comprising lyophilizing said sensitized erythrocytes.
Claim 11
Dependent Claim
37 words
The process of claim 9, wherein, prior to lyophilizing, the sensitized erythrocytes are re-suspended in a buffer solution having a pH of 5-8 and which contains sufficient glycine to protect the sensitized erythrocytes from damage during lyophilization.
Claim 12
Dependent Claim
21 words
The process of claim 10, wherein said buffer further comprises sufficient polyvinylpyrrolidone and gelatin to improve re-suspendability of the sensitized erythrocytes.
Claim 13
Dependent Claim
18 words
Sensitized, antigen-coated erythrocytes suitable for use in immunochemical hemagglutination diagnostic techniques prepared by the process of claim 1.
Claim 14
Dependent Claim
11 words
The product of claim 12, wherein said erythrocytes are sheep erythrocytes.
Claim 15
Dependent Claim
13 words
The product of claim 13, lyophilized and hermetically sealed in an inert atmosphere.
Claim 16
Dependent Claim
34 words
The product of claim 14, wherein the antigen or antigen-carrier protein conjugate is selected from the group consisting of human placenta lactogen, human chorionic gonadotrophin, dinitrophenyl-bovine gamma globulin and fluocortolone 40 bovine gamma globulin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-19 | 1980-04-19 | 1980-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-19 | 1984-04-19 | 1984-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-19 | 1988-04-19 | 1988-10-19 | $7700.00 | Window Closed / Lapsed |