Transmission-based optical detection systems

• US 20050243321A1
• Filed: 12/22/2004
• Published: 11/03/2005
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Atanassov, Zdravko Savov, Song, Xuedong, Feaster, Shawn Ray, Cohen, David Samuel, Knotts, Michael
• Granted Patent: US 7,796,266 B2
• Time in Patent Office: Days
• US Class Current: 356/432
• CPC Class Codes: G01N 21/00 Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light G01N3/00 - G01N19/00 take precedence
• CPC Class Codes: G01N 33/521 Single-layer analytical elements
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387

Abstract

A system that employs transmission-based detection techniques to determine the presence or concentration of an analyte within a test sample is provided. Specifically, the optical detection system contains a chromatographic-based assay device that is positioned in the electromagnetic radiation path defined between an illumination source and detector. To enhance the sensitivity and signal-to-noise ratio of the system without significantly increasing costs, the distance between the illumination source and/or detector and the assay device is minimized. The illumination source and/or detector may also be positioned directly adjacent to the assay device. In addition, the system may be selectively controlled to reduce reliance on external optical components, such as optical filters or diffusers.

Claims

1. An optical detection system for detecting the presence or quantity of an analyte residing in a test sample, said system comprising:

an assay device that includes a chromatographic medium in communication with detection probes, said detection probes being capable of producing a detection signal;

an illumination source capable of providing electromagnetic radiation that causes said detection probes to produce said detection signal; and

a detector capable of registering said detection signal produced by said detection probes, wherein said illumination source and said detector are positioned on opposing sides of said assay device so that said chromatographic medium is positioned in the electromagnetic radiation path defined between said illumination source and said detector, said chromatographic medium being transmissive to said electromagnetic radiation and said detection signal, wherein said illumination source, said detector, or both, are positioned less than about 5 millimeters from said assay device.

2. The optical detection system of claim 1, wherein said chromatographic medium include a porous membrane.

3. The optical detection system of claim 1, wherein said chromatographic medium includes a fluidic channel.

4. The optical detection system of claim 1, wherein a receptive material is immobilized within a detection zone defined by said chromatographic medium, said receptive material being configured to bind to at least a portion of said detection probes or complexes thereof.

5. The optical detection system of claim 1, wherein said illumination source is an electroluminescent device.

6. The optical detection system of claim 1, wherein said illumination source is an array of light-emitting diodes.

7. The optical detection system of claim 1, wherein said chromatographic medium is carried by a support.

8. The optical detection system of claim 7, wherein said illumination source is positioned adjacent to said chromatographic medium, and said detector is positioned adjacent to support.

9. The optical detection system of claim 7, wherein said illumination source is positioned adjacent to said support, and said detector is positioned adjacent to said chromatographic medium.

10. The optical detection system of claim 9, wherein said support functions as a diffuser for said illumination source.

11. The optical detection system of claim 1, wherein said detector contains an electronic imaging sensor capable of spatial discrimination.

12. The optical detection system of claim 1, wherein said detector contains a photodiode.

13. The optical detection system of claim 1, wherein said illumination source, said detector, or both, are positioned less than about 3 millimeters from said assay device.

14. The optical detection system of claim 1, wherein said illumination source, said detector, or both, are positioned less than about 2 millimeters from said assay device.

15. The optical detection system of claim 1, wherein said chromatographic medium is carried by said illumination source.

16. The optical detection system of claim 15, wherein said illumination source is laminated to a support for said chromatographic medium.

17. The optical detection system of claim 15, wherein said illumination source is laminated to said chromatographic medium.

18. The optical detection system of claim 15, wherein an optically transparent adhesive is used to laminate said illumination source to said chromatographic medium, to a support for said chromatographic medium, or combinations thereof.

19. The optical detection system of claim 10, wherein said assay device is contained within a sample holder.

20. The optical detection system of claim 19, wherein said illumination source is also positioned within said sample holder.

21. The optical detection system of claim 19, further comprising a cartridge that contains said illumination source, said cartridge defining a port that receives said sample holder.

22. An optical detection system for detecting the presence or quantity of an analyte residing in a test sample, said system comprising:

an assay device that includes a porous membrane carried by a support, said porous membrane being in communication with detection probes, said detection probes being capable of producing a detection signal;

an illumination source capable of providing electromagnetic radiation that causes said detection probes to produce said detection signal; and

a detector capable of registering said detection signal produced by said detection probes, wherein said illumination source and said detector are positioned on opposing sides of said assay device so that said porous membrane is positioned in the electromagnetic radiation path defined between said illumination source and said detector, said porous membrane and said support being transmissive to said electromagnetic radiation and said detection signal, wherein said illumination source, said detector, or both, are positioned less than about 5 millimeters from said assay device.

23. The optical detection system of claim 22, wherein said illumination source is positioned adjacent to said porous membrane, and said detector is positioned adjacent to support.

24. The optical detection system of claim 22, wherein said illumination source is positioned adjacent to said support, and said detector is positioned adjacent to said porous membrane.

25. The optical detection system of claim 22, wherein said illumination source, said detector, or both, are positioned less than about 3 millimeters from said assay device.

26. The optical detection system of claim 22, wherein said illumination source, said detector, or both, are positioned less than about 2 millimeters from said assay device.

27. The optical detection system of claim 22, wherein said illumination source is an electroluminescent device.

28. The optical detection system of claim 22, wherein said illumination source is an array of light-emitting diodes.

29. The optical detection system of claim 22, wherein said detector contains an electronic imaging sensor capable of spatial discrimination.

30. The optical detection system of claim 22, wherein said detector contains a photodiode.