Reducing Optical Interference in a Fluidic Device

• US 20100291609A1
• Filed: 03/13/2007
• Published: 11/18/2010
• Est. Priority Date: 10/13/2006
• Status: Active Grant

• Current Assignee: Labrador Diagnostics LLC (SoftBank Group Corp.)
• Original Assignee: Theranos Incorporated
• Inventors: Gibbons, Ian, O'Connell, Michael
• Granted Patent: US 8,008,034 B2
• Time in Patent Office: Days
• US Class Current: 435/21
• 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 2200/14 Process control and prevention of errors
• CPC Class Codes: B01L 2200/16 Reagents, handling or storing thereof
• CPC Class Codes: B01L 2300/069 Absorbents; Gels to retain a fluid
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: G01N 33/5304 Reaction vessels, e.g. agglutination plates for solid-phase systems G01N33/543
• CPC Class Codes: G01N 33/536 with immune complex formed in liquid phase
• CPC Class Codes: G01N 33/542 with steric inhibition or signal modification, e.g. fluorescent quenching
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

This invention is in the field of medical devices. Specifically, the present invention provides portable medical devices that allow real-time detection of analytes from a biological fluid. The methods and devices are particularly useful for providing point-of-care testing for a variety of medical applications. In particular, the medical device reduces interference with an optical signal which is indicative of the presence of an analyte in a bodily sample.

Claims

1. A method of detecting an analyte in a sample, comprising:

allowing a sample suspected to contain the analyte to react with at least one reactant contained in a fluidic device that comprises;

an assay assembly configured to yield an optical signal that is indicative of the presence of the analyte; and

an quencher assembly in fluidic communication with said assay assembly, wherein said quencher assembly is adapted to reduce interference of said optical signal; and

detecting said optical signal thereby detecting the analyte in the sample.

2. The method of claim 1, wherein said assay assembly comprises reagent chambers comprising at least one reagent used in said assay and at least one reaction site comprising a reactant that binds said analyte.

3. The method of claim 2, wherein said at least one reagent comprises an enzyme conjugate and an enzyme substrate.

4. The method of claim 2, wherein said quencher assembly comprises a quenching site in fluidic communication with said reaction site and a quenching agent at said quenching site.

5. The method of claim 4, wherein said quencher assembly further comprises an absorbent material.

6. The method of claim 5, wherein said absorbent material is impregnated with said quenching agent.

7. The method of claim 5, wherein said absorbent material is selected from the group consisting of glass fiber, silica, paper, polyacylamide gel, agarose, and agar.

8. The method of claim 5, wherein said quenching agent is adapted to inactivate at least one reagent from said assay, thereby reducing said interference of said optical signal.

9. A method of manufacturing a fluidic device having a quencher assembly, comprising:

providing a plurality of layers of the fluidic device;

affixing said layers together to provide for a fluidic network between a sample collection unit, at least one reagent chamber, at least one reaction site, and at least one quencher assembly.

10. The method of claim 9, wherein said affixing comprising ultrasonically welding said layers together.

11. The method of claim 9, wherein said quencher assembly comprises a quenching site in fluidic communication with said at least one reaction site and a quenching agent at said quenching site.

12. The method of claim 11, wherein said quencher assembly further comprises an absorbent material.

13. The method of claim 12, wherein said absorbent material is impregnated with said quenching agent.

14. The method of claim 12, wherein said absorbent material is selected from the group consisting of glass fiber, silica, paper, polyacylamide gel, agarose, and agar.

15. The method of claim 13, wherein said quenching agent is 4-amino-1,11-azobenzene-3,41-disulfonic acid.

16. A fluidic device for detecting an analyte in a sample, comprising:

a sample collection unit;

an assay assembly comprising

at least one reaction site, said reaction site comprising a surface and a reactant that binds an analyte immobilized thereto;

a first reagent chamber comprising an enzyme conjugate;

a second reagent chamber comprising an enzyme substrate, wherein the enzyme substrate reacts with the enzyme conjugate to produce a luminescent signal; and

fluidic channels that connect the reagent chambers with the at least one reaction site;

a quencher assembly comprising an absorbent material and a quenching agent, wherein the quenching agent diminishes the reaction between the enzyme conjugate and the enzyme substrate; and

a plurality of fluidic channels that connect the sample collection unit and the quencher assembly with the assay assembly.

17. The fluidic device of claim 16, wherein said quencher assembly further comprises a waste chamber connected through a fluid channel with the assay assembly, wherein the waste chamber comprises the absorbent material.

18. The fluidic device of claim 16, wherein said absorbent material is selected from the group consisting of glass fiber, silica, paper, polyacylamide gel, agarose, or agar.

19. The fluidic device of claim 18, wherein said quenching agent is 4-amino-1,11-azobenzene-3,41-disulfonic acid and said enzyme conjugate is an alkaline phosphotase-labeled reagent.

20. The fluidic device of claim 16, wherein said assay assembly is adapted to run an immunoassay.