Method and apparatus for assaying liquid materials

• US 3,953,172 A
• Filed: 05/10/1974
• Issued: 04/27/1976
• Est. Priority Date: 05/10/1974
• Status: Expired due to Term

• Current Assignee: Ventrex Laboratories, Inc.
• Original Assignee: Union Carbide Corporation (Dow, Inc.)
• Inventors: Shapiro, Stephen I., Ertingshausen, Gerhard
• Primary Examiner(s): Serwin, R. E.
• Application Number:
  US05/468,649
• Time in Patent Office: 718 Days
• Field of Search: 23/230 R, 23/230 B, 23/253 R, 23/259, 233/26, 210/31 C, 210/198 C, 210/520, 210/DIG. 23, 424/1, 73/61.1 C
• US Class Current: 436/500
• CPC Class Codes: B04B 5/0421 pivotably mounted

Abstract

Assaying of fluids to determine the level of a substance in a fluid sample such as blood serum involving the reacting of fluid samples with one or more reagents and centrifugally separating reaction constituents and measuring a property of a reaction constituents.

Claims

1. A method for assaying a plurality of liquid samples which comprises

i. reacting at least two liquid materials in a plurality of cavities to provide a liquid containing at least one reaction product

ii. providing liquid phase separating means in communication with said cavities

iii. subjecting said cavities and said liquid phase separating means to centrifugal force sufficient to transfer the liquid contents of said cavities to said communicating liquid phase separating means and provide separation of the liquid transferred thereto into at least two phases, and

iv. measuring at least one property of a separated phase.

2. A method in accordance with claim 1, wherein at least one of said liquid materials contains a radioactive constituent and the property measured in step (iv) is radioactivity.

3. A method in accordance with claim 1 wherein transfer of the contents of said cavities to said liquid phase separating means occurs at a time when increasing amounts of at least one reaction product at being formed.

4. A method in accordance with claim 1 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means by centrifugal force developed by rotation of said rotatable means.

5. A method in accordance with claim 1 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means to a vessel in communication therewith by centrifugal force.

6. A method in accordance with claim 1 wherein said phase transferred to said vessel is radioactive.

7. A method in accordance with claim 1 wherein at least one property of said phase transferred to said vessel is measured.

8. A method in accordance with claim 1 wherein a liquid is introduced into said cavities subsequent to the transfer of liquid to said liquid phase separating means and during rotation thereof to provide an eluent in said liquid phase separating means upon transfer thereto by centrifugal force.

9. A method in accordance with claim 1 wherein at least one of said cavities contains liquid materials which provide upon reaction a definitive value of measurable property in at least one of said separated phases.

10. A method for assaying a plurality of liquid samples which comprises

i. providing liquid material in a plurality of substantially circularly disposed first cavities

ii. providing a different liquid material, reactable with said material in said first cavities, in a plurality of substantially circularly disposed second cavities

iii. providing a plurality of liquid phase separating means in a substantially circular arrangement, said first and second cavities and said liquid phase separating means being arranged substantially concentric about a common axis with said liquid phase separating means being at a further radial distance than said second cavities and said second cavities being at a further radial distance than said first cavities, said liquid phase separating means being in tandem communication with a second cavity which is in tandem communication with a first cavity;

iv. causing rotation of said cavities about said common axis to develop a centrifugal force sufficient to cause liquid in said first cavities to be transferred to said second cavities to react with said liquid in said second cavities to produce at least one reaction product

v. subsequently causing rotation of said cavities and said liquid phase separating means at a speed to develop a centrifugal force sufficient to transfer the liquid contents of said second cavities to said liquid phase separating means

vi. continuing rotation of said liquid phase separating means to develop a centrifugal force sufficient to separate the liquid transferred thereto into at least two phases and

vii. measuring at least one property of at least one of said phases.

11. A method in accordance with claim 10 wherein at least one of said liquid material contains a radioactive constituent and the property measured in step (vii) is radioactivity.

12. A method in accordance with claim 10 wherein transfer of the contents of said second cavities to said liquid phase separating means occurs at a time when increasing amounts of at least one reaction product are being formed.

13. A method in accordance with claim 10 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means by centrifugal force developed by rotation of said rotatable means.

14. A method in accordance with claim 10 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means to a vessel in communication therewith by centrifugal force.

15. A method in accordance with claim 10 wherein a liquid is introduced into at least said second cavities subsequent to the transfer of liquid to said liquid phase separating means and during rotation thereof to provide an eluent in said liquid phase separating means upon transfer thereto by centrifugal force.

16. A method in accordance with claim 10 wherein at least one of said first cavities and one of said second cavities contain liquid materials which provide upon reaction a definitive value of a measurable property in at least one of said separated phases.

17. A method for assaying a plurality of liquid samples which comprises

i. providing rotatable means having rotatable therewith a plurality of first and second cavities each of said cavities being adapted to contain liquid and said cavities being arranged in communication with each other such that upon development of a sufficient centrifugal force by rotation of said rotatable means, liquid in a said first cavity is transferred to said second cavity, and upon development of a sufficient centrifugal force by rotation of said rotatable means liquid in a said second cavity is transferred out of said second cavity

ii. providing at least one liquid material in a plurality of said first cavities and at least one different liquid material in a plurality of said second cavities said materials being such that upon contact therebetween interaction occurs to provide in said second cavities a mixture having at least one separatable constituent capable of being separated from said mixture by liquid phase separating means

iii. causing rotation of said rotatable member to develop a centrifugal force sufficient to transfer the liquid contents of said first cavities to the second cavities to contact the liquid contents of the second cavities to provide a mixture confined in said second cavity containing at least one separatable constituent capable of being separated from said mixture by liquid phase separating means

iv. providing liquid phase separating means in communication with said second cavities and arranged to be rotatable therewith and be subjected to centrifugal force developed by rotation of said rotatable means

v. adjusting the speed of the rotatable means at a time subsequent to the formation of said separatable constituent in said second cavities to the extent that there is provided a centrifugal force sufficient to transfer the mixture in said second cavities to said liquid phase separating means,

vi. continuing rotation of said rotatable means to provide a centrifugal force acting upon the mixture transferred to said liquid phase separating means sufficient to cause said mixture to be separated into at least two phases, one of said phases containing at least one of said separatable constituent of said mixture and

vii. measuring at least one property of a said phase containing said at least one separatable constituent.

18. A method in accordance with claim 17 wherein

i. said at least one liquid material provided in said first cavity contains at least one reactive constituent;

ii. said at least one liquid material provided in said second cavity contains at least one reactive constituent,

iii. said reactive constituents, upon transfer of the liquid contents of said first cavity to said second cavity, proceed to react in said second cavity with the formation of a reaction product

iv. one of said at least two phases separated in said liquid phase separating means contains substantially all of at least one, but not all of said reactive constituents in said mixture transferred to said liquid phase separating means.

19. A method in accordance with claim 17 wherein at least one of said liquids contains a radioactive constituent and the property measured in step (vii) is radioactivity.

20. A method in accordance with claim 18 wherein at least one of said reactable constituents is radioactive.

21. A method in accordance with claim 18 wherein transfer of the contents of the second cavity to said liquid phase separating means occurs at a time when the reactive constituents are reacting with the formation of increasing amounts of reaction product.

22. A method in accordance with claim 17 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means by centrifugal force developed by rotation of said rotatable means.

23. A method in accordance with claim 17 wherein at least one of said phases separated in said liquid phase separating means is transferred from said liquid phase separating means to a vessel in communication therewith by centrifugal force developed by rotation of said rotatable means.

24. A method in accordance with claim 23 wherein said phase transferred to said vessel is radioactive.

25. A method in accordance with claim 23 wherein at least one property of said phase transferred to said vessel is measured.

26. A method in accordance with claim 17 hwerein at least one of said first cavities and one oof said second cavities contain liquid materials which provide upon reaction a definitive value of a measurable property in at least one of said separated phases.

27. A method in accordance with claim 17 wherein a liquid is introduced into at least said second cavities subsequent to the transfer of liquid to said liquid phase separating means and during rotation thereof to provide an eluent in said liquid phase separating means upon transfer thereto by centrifugal force.

28. Assay apparatus comprising a

i. rotatable member having a plurality of substantially circularly disposed first cavities adapted to contain liquid and a plurality of substantially circularly disposed second cavities adapted to contain liquid

ii. a plurality of liquid phase separating means arranged in a substantially circular arrangement and engaged to said rotatable member, said first and second cavities and said liquid phase separating means being arranged substantially concentric about a common axis with said liquid phase separating means being at a further radial distance than said second cavities and said second cavities being at a further radial distance that said first cavities, said liquid phase separating means being in tandem communication with a second cavity which is in tandem communication with a first cavity and (iii) collecting means adapted to contain liquid engaged to said liquid phase separating means to receive liquid separated by said liquid phase separating means.

29. Assay apparatus comprising

i. rotating means

ii. a disc shaped member adapted to be rotated in a substantially horizontal plane about its central axis by said rotating means, said disc member having a first row of a plurality of cavities adapted to contain liquid at a common radial distance from the central axis of said disc and a second row of a plurality of cavities adapted to contain liquid at a different and greater common radial distance from said first row, cavities of said first row being in substantial radial aligment with cavities of said second row;

iii. first trough-like means having an upward slope between aligned cavities of said first row and said second row to provide communication therebetween for liquid over flowing from a cavity of said first row to a radially aligned cavity of said second row due to centrifugal force;

iv. a plurality of liquid phase separating means substantially in radial alignment with cavities of said second row and adapted to be rotated by said rotating means;

v. second trough-like means having an upward slope between the aligned cavities of said second row and said liquid phase separating means to provide communication therebetween for liquid overflowing from a cavity of said second row due to centrifugal force, said second trough-like means having a steeper slope than said first trough like means such that a centrifugal force required to cause overflow of liquid from the cavities of the second row is greater than the centrifugal force required to cause overflow of liquid from the cavities of the first row.

30. Apparatus in accordance with claim 29 wherein said plurality of liquid phase separating means are in the form of individual pivotally mounted columns adapted to be displaced by centrifugal force to positions wherein the longitudinal axis of said columns extend substantially radially with respect to the central axis of said disc shaped member.

31. Apparatus for use with a centrifugal assay device comprising

i. a disc shaped member adapted to be rotated in a substantially horizontal plane about its central axis, said disc shaped member having a first row of a plurality of cavities adapted to contain liquid at a common radial distance from the central axis of said disc and a second row of a plurality of cavities adapted to contain liquid at a different and greater common radial distance from said first row, cavities of said first row being in substantial radial alignment with cavities of said second row;

ii. first trough-like means having an upward slope between aligned cavities of said first row and said second row to provide communication therebetween for liquid over flowing from a cavity of said first row to a radially aligned cavity of said second row due to centrigugal force;

iii. second trough-like means having an upward slope at the radially outermost portion of the aligned cavities of said second row to provide exit therefrom for liquid overflowing from a cavity of said second row due to centrifugal force, said second trough-like means having a steeper slope than said first trough-like means such that a centrifugal force required to cause overflow of liquid from the cavities of the second row is greater than the centrifugal force required to cause overflow of liquid from the cavities of the first row.