Self-contained assay assembly and apparatus

• US 5,310,523 A
• Filed: 08/27/1991
• Issued: 05/10/1994
• Est. Priority Date: 06/15/1990
• Status: Expired due to Term

• Current Assignee: Siemens Healthcare Diagnostics Incorporated (Siemens AG)
• Original Assignee: Chiron Corporation (Bayer AG)
• Inventors: Shadel, Robert R., Smethers, Rick T., Urdea, Michael S., Warner, Brian D., Leytes, Lev J.
• Primary Examiner(s): Housel, James C.
• Assistant Examiner(s): Ludlow, Jan M.
• Application Number:
  US07/750,325
• Time in Patent Office: 987 Days
• Field of Search: 435/299-301, 435/810, 435/6, 435/287, 435/312, 435/291, 435/7.1, 422/57, 422/58, 422/61, 422/72, 422/102, 436/809, 436/165, 436/518
• US Class Current: 422/404
• CPC Class Codes: C12Q 1/6813 Hybridisation assays
• CPC Class Codes: C12Q 1/682 Signal amplification
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing

Abstract

A self-contained assembly for assaying an analyte in a liquid sample. The pair of disc-like rotatable plates forming the assembly are relatively rotatable to align reagent reservoirs in one plate with a reaction well in the other plate, for sequential addition of multiple reagents, either in liquid or solid form, to the reaction well. In one embodiment, the reaction well includes solid-phase particles which can be transferred from the reaction well to spaced wells in the assembly by a combination of relative movement of the plate, and rotation of the entire assembly.

Claims

1. A self-contained assembly for detecting an analyte ligand by detectable, analyte-specific binding to a solid support, comprising

a reaction plate defining a well that contains a solid support, said well being capable of holding liquid reagents in contact with the support,

adjacent the reaction plate, a transfer plate containing first and second reagent reservoirs, each said reservoir being formed by an elastomeric sleeve held in a channel which extends through the transfer plate, said transfer and reaction plates being spaced relative to one another, in the region of the sleeve, to form a capillary lock effective to prevent liquid from leaking from the reservoir by capillarity,

carried in said first and second reservoirs, first and second reaction reagents, respectively, required for binding of ligand in detectable form to the solid support, and

means for mounting the transfer plate on the reaction plate for movement thereon to a sample-addition position at which sample can be added to said well, a first reagent-transfer position at which the first reservoir is aligned with said well, a wash position at which wash solution can be introduced into the well, and a second reagent-transfer position at which the second reservoir is aligned with said well,

wherein said sleeve is effective to prevent release of each said reagent from its respective reservoir until that reservoir is aligned with said well.

2. The assembly of claim 1, wherein at least one of said first and second reagents is in the form of a liquid solution.

3. The assembly of claim 1, which further includes a cover plate secured to the reaction plate, said cover plate having ports which are alignable with said reservoirs when the transfer plate is in one of said first and second reagent transfer positions, and said sleeve is effective to form a seal between the transfer plate and both the reaction and cover plates.

4. The assembly of claim 1, wherein the reaction plate includes a chamfered opening disposed above said well for communicating said reservoirs in the transfer plate with the well in the reaction plate.

5. The assembly of claim 1, wherein at least one of said first and second reagents is a pelletized reagent, and the pelletized reagent is delivered from one of said first and second reagent reservoirs to said well by gravity, when said one reagent reservoir is aligned with the reaction well.

6. The assembly of claim 1, wherein said mounting means allows rotation of the reaction and transfer plates relative to one another.

7. The assembly of claim 1, for use in an immunoassay for detection of a ligand effective to bind immunospecifically to the solid support, wherein said first reaction reagent includes an antiligand reagent capable of binding immunospecifically with such ligand, when the ligand is bound to the support, and said second reaction reagent includes a reagent capable of reacting with the antiligand reagent to produce a detectable signal on the solid support.

8. A self-contained assembly for detecting an analyte ligand by detectable, analyte-specific binding to a solid support, said assembly being intended for use with a heater effective to heat the well in the assembly, said assembly comprising

a reaction plate defining a well that holds a solid support, said well being capable of holding liquid reagents in contact with the support,

adjacent the reaction plate, a transfer plate containing first and second reagent reservoirs,

carried in said first and second reservoirs, first and second reaction reagents, respectively, required for binding of ligand in detectable form to the solid support,

means for mounting the transfer plate on the reaction plate for movement thereon to a sample-addition position at which sample can be added to said well, a first reagent-transfer position at which the first reservoir is aligned with said well, a wash position at which wash solution can be introduced into the well, and a second reagent-transfer position at which the second reservoir is aligned with said well,

a cover plate attached to the reaction plate such that the transfer plate lies between the reaction plate and the cover plate,

means for sealing the well when the well is heated, said sealing means including (a) a sealing pad carried in the transfer plate for traveling in a direction normal to the plane of the transfer plate, and (b) means on the cover plate for biasing the pad against the well, when the transfer plate is moved to a heating position, and

means for preventing release of each said reagent from its respective reservoir until that reservoir is aligned with said well.

9. The assembly of claim 8, for use in a DNA probe assay, wherein said analyte ligand includes a nucleic acid with a known target sequence, the solid support is coated with immobilized nucleic acid fragments, said first reagent includes a probe effective to hybridize with both the target sequence and the immobilized fragments, and said second reagent includes a reporter molecule effective to bind, directly or indirectly, to said probe.

10. The assembly of claim 9, wherein said first reagent additionally includes a denaturation agent, and said transfer plate further includes a third reservoir containing an annealing buffer, said third reservoir being alignable with said well to allow transfer of said third reagent to said well.

11. The assembly of claim 10, wherein said transfer plate further includes a fourth reservoir containing a branched nucleic acid fragment effective to bind directly or indirectly to said analyte ligand, and said reporter molecule is effective to bind to the branched fragment.

12. A self-contained assembly for assaying, in a liquid sample, an analyte nucleic acid having a known target sequence, comprising

a reaction plate containing a reaction well formed by an elongate, radially extending channel and a solid-phase surface contained in the well and coated with immobilized nucleic acid fragments,

a cover plate secured to the reaction plate, and having ports which are alignable with spaced areas of said well,

an intermediate transfer plate which includes first, second, third, and fourth reagent reservoirs containing, respectively, (1) a first reagent which includes a denaturation agent and a probe effective to bind to the analyte DNA and to said immobilized fragments, (2) a second reagent which includes an annealing buffer, (3) a third reagent which includes branched nucleic acid fragments effective to bind, directly or indirectly, to said analyte, and (4) a fourth reagent which includes reporter-labeled fragments effective to bind to the branched fragments, where the four reagent reservoirs are designed for sequential addition to said reaction reservoir, said transfer plate further having ports which are alignable with the ports in the cover plate, when the transfer plate is moved to a wash position, providing an enclosed passageway for circulating a solution through said well,

means for mounting the transfer plate between the reaction and cover plates for relative rotation with respect thereto, from a home position, at which said first, second, third, and fourth reservoirs are isolated from said well, to first, second, third, and fourth transfer positions at which the first, second, third, and fourth reservoirs are aligned with said well, allowing sequential transfer of the first, second, third, and fourth reagents, respectively, to said well, and

means for preventing release of each said reagent from its respective reservoir until that reservoir is aligned with said well.

13. A self-contained assembly for detecting an analyte ligand by detectable, analyte-specific binding to a solid support, comprising

a reaction plate defining a well that contains a solid support, said well being capable of holding liquid reagents in contact with the support, said well being formed by an elongate channel,

adjacent the reaction plate, a transfer plate containing first and second reagent reservoirs, said transfer plate including wash ports which are alignable with spaced areas in the channel, when the transfer plate is moved to a wash position, forming an enclosed passageway between said reaction plate and said transfer plate for passing a wash solution through the channel, and carried in said first and second reservoirs, first and second reaction reagents, respectively, required for binding of ligand in detectable form to the solid support,

means for mounting the transfer plate on the reaction plate for movement thereon to a sample-addition position at which sample can be added to said well, a first reagent-transfer position at which the first reservoir is aligned with said well, a wash position at which said wash ports are aligned with said well so that wash solution can be introduced into the well, and a second reagent-transfer position at which the second reservoir is aligned with said well, and

means for preventing release of each said reagent from its respective reservoir until that reservoir is aligned with said well.