Fluidics-based assay devices

• US 7,314,763 B2
• Filed: 08/27/2002
• Issued: 01/01/2008
• Est. Priority Date: 08/27/2002
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Feaster, Shawn, Yang, Kaiyuan, Song, Xuedong, Kaylor, Rosann
• Primary Examiner(s): Le; Long V.
• Assistant Examiner(s): Do; Pensee T.
• Application Number:
  US10/228,838
• Publication Number:
  US 20040043507A1
• Time in Patent Office: 1,953 Days
• Field of Search: 436/518, 436/526, 436/8, 436/546, 436/538, 436/166, 435/969, 435/970
• US Class Current: 436/526
• CPC Class Codes: B01L 2200/0668 Trapping microscopic beads
• CPC Class Codes: B01L 2300/0825 Test strips
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/043 magnetic forces
• CPC Class Codes: B01L 2400/0677 phase change valves; Meltable, freezing, dissolvable plugs; Destructible barriers
• 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 33/54333 Modification of conditions of immunological binding reaction, e.g. use of more than one type of particle, use of chemical agents to improve binding, choice of incubation time or application of magnetic field during binding reaction
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: Y10S 435/969 Multiple layering of reactants
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing

Abstract

A fluidics-based assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes a self-calibrated magnetic binding assay format (e.g., sandwich, competitive, etc.) that includes detection probes capable of generating a detection signal (e.g., fluorescent non-magnetic particles) and calibration probes capable of generating a calibration signal (e.g., fluorescent magnetic particles). The amount of the analyte within the test sample is proportional (e.g., directly or inversely) to the intensity of the detection signal calibrated by the intensity of the calibration signal. It has been discovered that the fluidics-based device of the present invention provides an accurate, inexpensive, and readily controllable method of determining the presence of an analyte in a test sample.

Claims

1. A fluidics-based assay device for detecting the presence or quantity of an analyte residing in a test sample, the device comprising:

a reaction chamber for containing the test sample;

detection probes that comprise particles that are conjugated with a first specific binding member for the analyte and labeled with a first detectable substance, the first detectable substance being capable of producing a detection signal;

calibration probes that comprise magnetic particles labeled with a detectable substance second, the detectable substance second being capable of producing a calibration signal;

wherein the first and second detectable substances are different

non-fluorescent magnetic particles that are conjugated with a second specific binding member for the analyte;

a channel in fluid communication with the reaction chamber, the channel defining a detection zone; and

a magnetic device positioned adjacent to the detection zone;

wherein the amount of the analyte within the test sample is directly or inversely proportional to the intensity of the detection signal produced at the detection zone calibrated by the intensity of the calibration signal produced at the detection zone.

2. The assay device of claim 1, wherein the detectable substance of both the detection probes and the calibration probes is selected from the group consisting of fluorescent compounds, chemiluminescent compounds, phosphorescent compounds, and combinations thereof.

3. The assay device of claim 1, wherein the amount of the analyte within the test sample is directly or inversely proportional to the intensity of the detection signal produced at the detection zone divided by the intensity of the calibration signal produced at the detection zone.

4. The assay device of claim 1, wherein the amount of the analyte within the test sample is directly proportional to the intensity of the detection signal produced at the detection zone calibrated by the intensity of the calibration signal produced at the detection zone.

5. The assay device of claim 1, wherein the amount of the analyte within the test sample is inversely proportional to the intensity of the detection signal produced at the detection zone calibrated by the intensity of the calibration signal produced at the detection zone.

6. The assay device of claim 1, wherein the channel facilitates capillary flow of the test sample.

7. The assay device of claim 1, further comprising a barrier disposed between the reaction chamber and the channel, the barrier being configured to hold the test sample within the reaction chamber for a certain period of time.

8. The assay device of claim 7, wherein the barrier is configured to substantially dissolve.

9. The assay device of claim 8, wherein the barrier contains a material selected from the group consisting of carbohydrates, salts, and combinations thereof.

10. The assay device of claim 7, wherein the barrier is configured to physically rupture.

11. The assay device of claim 1, wherein the detectable substance of both the detection probes and the calibration probes is a fluorescent compound.

12. The assay device of claim 1, wherein the detection probes comprise non-magnetic particles labeled with a fluorescent compound.

13. The assay device of claim 1, wherein the calibration probes comprise magnetic particles labeled with a fluorescent compound.

14. The assay device of claim 13, wherein the fluorescent magnetic particles are blocked.

15. The assay device of claim 13, wherein the fluorescent magnetic particles are conjugated with a specific binding member.

16. The assay device of claim 1, wherein the detection probes, the calibration probes, or combinations thereof comprise a specific binding member.

17. The assay device of claim 1, wherein the specific binding member is selected from the group consisting of antigens, haptens, aptamers, antibodies, and complexes thereof.