Systems, devices, and methods for agglutination assays using sedimentation

• US 9,244,065 B1
• Filed: 03/16/2012
• Issued: 01/26/2016
• Est. Priority Date: 03/16/2012
• Status: Active Grant

• Current Assignee: National Technology & Engineering Solutions Of Sandia LLC (Honeywell International Inc.)
• Original Assignee: Sandia Corporation (Martin Marietta Corporation)
• Inventors: Schaff, Ulrich Y., Sommer, Gregory J., Singh, Anup K.
• Primary Examiner(s): Nguyen, Bao-Thuy
• Assistant Examiner(s): Crawford, Erik B
• Application Number:
  US13/423,073
• Time in Patent Office: 1,411 Days
• Field of Search: 436/824, 436/518, 436/536, 436/538, 436/523, 436/528, 435/287.2, 435/7.1, 435/287.1, 435/7.92, 435/7.94, 435/969
• US Class Current: 1/1
• CPC Class Codes: B01D 21/262 by using a centrifuge
• CPC Class Codes: B01L 2200/0631 Purification arrangements, e.g. solid phase extraction [SPE]
• CPC Class Codes: B01L 2200/0647 Handling flowable solids, e.g. microscopic beads, cells, particles
• CPC Class Codes: B01L 2200/10 Integrating sample preparation and analysis in single entity, e.g. lab-on-a-chip concept
• CPC Class Codes: B01L 2300/0627 Sensor or part of a sensor is integrated
• CPC Class Codes: B01L 2300/0803 Disc shape
• CPC Class Codes: B01L 2300/0861 Configuration of multiple channels and/or chambers in a single devices
• CPC Class Codes: B01L 2400/0409 centrifugal forces
• CPC Class Codes: B01L 2400/0457 passive flow or gravitation
• CPC Class Codes: B01L 3/5021 Test tubes specially adapted for centrifugation purposes centrifuges B04B5/04
• CPC Class Codes: B01L 3/50215 using a float to separate phases
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 3/502753 characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation separation in general B01D; microapparatus for analysis using electrophoresis G01N27/44791; sample preparation G01N1/28
• CPC Class Codes: B01L 3/502761 specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules investigating characteristics of particles G01N15/00
• CPC Class Codes: G01N 33/537 with separation of immune complex from unbound antigen or antibody
• CPC Class Codes: G01N 33/538 by sorbent column, particles or resin strip , i.e. sorbent materials
• CPC Class Codes: G01N 33/543 with an insoluble carrier for immobilising immunochemicals
• CPC Class Codes: G01N 33/54313 the carrier being characterised by its particulate form
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing

Abstract

Embodiments of the present invention include methods for conducting agglutination assays using sedimentation. Aggregates may be exposed to sedimentation forces and travel through a density medium to a detection area. Microfluidic devices, such as microfluidic disks, are described for conducting the agglutination assays, as are systems for conducting the assays.

Claims

1. A method comprising:

layering a mixture on a density medium, wherein the mixture includes a sample and a first population of coated beads having a first density, wherein the first population of coated beads include affinity reagents for an analyte of interest, wherein the first population of coated beads is configured to form aggregates with the analyte interest when present, wherein the density medium has a minimum density greater than the first density;

subjecting the mixture to sedimentation forces such that the aggregates, if formed, travel through the density medium; and

detecting a presence of the aggregates in a detection area.

2. The method of claim 1, the mixture further comprising a second population of coated beads having a second density, and wherein the minimum density of the density medium is less than the second density.

3. The method of claim 2 wherein the first population of coated beads further include a detection label.

4. The method of claim 2, wherein the first population of coated beads are configured to remain at an interface between the sample and the density medium responsive to the sedimentation forces if the first population of coated beads are not bound in the aggregates.

5. The method of claim 2, wherein the first population of coated beads are configured to form the aggregates with the analyte of interest and the second population of coated beads, such that the detection label travels to the detection area responsive to the sedimentation forces.

6. The method of claim 1, wherein the sedimentation forces are generated by gravity.

7. The method of claim 1, wherein the sedimentation forces are generated by centrifugal force.

8. The method of claim 1, wherein said subjecting the mixture to sedimentation forces comprises subjecting the mixture to sedimentation forces for a fixed time.

9. The method of claim 8, wherein the fixed time is selected such that the aggregates of the coated beads and analyte of interest are configured to travel to the detection area within the fixed time and unbound coated beads do not reach the detection area within the fixed time.

10. The method of claim 1, further comprising preparing the mixture including mixing the sample with the coated beads.

11. The method of claim 1, wherein said layering a mixture on a density medium comprises providing the mixture on the density medium in a vial.

12. The method of claim 1, wherein said layering a mixture on a density medium comprises inputting the mixture to a reservoir of a microfluidic device containing the density medium.

13. The method of claim 1, wherein said detecting comprises quantifying an amount of the analyte of interest.

14. The method of claim 1, wherein the analyte of interest comprises a protein.