METHOD AND DEVICE FOR OPTICAL DETECTION OF SUBSTANCES IN A LIQUID OR GASEOUS MEDIUM

• US 20090069199A1
• Filed: 07/16/2008
• Published: 03/12/2009
• Est. Priority Date: 07/16/2007
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Brandenburg, Albrecht
• Granted Patent: US 8,877,129 B2
• Time in Patent Office: Days
• US Class Current: 506/39
• CPC Class Codes: G01N 21/6452 Individual samples arranged in a regular 2D-array, e.g. multiwell plates
• CPC Class Codes: G01N 21/648 using evanescent coupling or surface plasmon coupling for the excitation of fluorescence
• CPC Class Codes: G01N 21/7703 using reagent-clad optical fibres or optical waveguides using measurement of total internal reflection or attenuated total reflection G01N21/552; optical fibres or waveguides per se G02B
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: G01N 33/544 the carrier being organic
• CPC Class Codes: G01N 33/552 Glass or silica

Abstract

The invention relates to a device for optical detection of substances in a liquid or gaseous medium, with a substrate with molecules for detecting the substances that are to be detected, wherein these molecules are immobilised at a surface of the substrate or in the substrate and wherein the substances that are to be detected can essentially be selectively bound to these molecules, wherein light waves can be coupled into the substrate and can be guided through this, and wherein the substrate is a foil element made of a transparent material in which a coupling structure for coupling the light waves is integrally formed and in which the coupled light waves can be guided.

Claims

1. Device for optical detection of substances in a liquid or gaseous medium, with a substrate with molecules for detecting the substances that are to be detected, said molecules being immobilised at a surface of the substrate or in the substrate and to which the substances that are to be detected can essentially be selectively bound, wherein light waves can be coupled into the substrate and can be guided through it, wherein the substrate is a foil element made of a transparent material in which a coupling structure for coupling the light waves is integrally formed and in which the coupled light waves can be guided.

2. Device according to claim 1, wherein the coupling structure is formed at the surface of the foil element during the forming step of the foil element in one step, together with the formation of the foil element itself.

3. Device according to claim 2, wherein the foil element is manufactured from a liquid medium by stamping, rolling, casting or hardening.

4. Device according to claim 3, wherein the coupling structure is formed in the mould used during stamping, rolling or injection moulding in such a way that the coupling structure can be manufactured with this mould in one step simultaneously with the manufacture of the foil element, and particularly its surface.

7. Device according to claims 1, comprising a multiplicity of molecules for detecting the substances that are to be detected, wherein these molecules are immobilised on the surface of the foil element or in the foil element and form a readout field with a multiplicity of measurement points for spatially-resolved detection of the substances that are to be detected.

8. Device according to claim 1, wherein the foil element has an homogenizing area that is arranged in the beam path downstream of the coupling structure and upstream of a measurement point, particularly before the readout field, so that the light waves coupled into the foil element via the coupling structure have a homogenous depression before reaching the measurement point.

9. Device according to claims 1, wherein an element that homogenizes the light waves, particularly a diffractive optical element such as a grating structure, is provided in the beam path downstream of the coupling structure and upstream of the measurement point.

10. Device according to claim 9, wherein the coupling structure has a curvature, comparable to a cylinder lens or a round form, in order to achieve homogenous distribution of the light waves that are coupled into the foil element via the coupling structure.

11. Device according to claim 10, wherein the coupling structure is a refractive optical element, such as a prism or a grating or a structure with a trapezoidal or rectangular cross-section.

12. Device according to claim 10, wherein the coupling structure is a diffractive optical element.

13. Device according to claim 1, wherein a thickness of the foil element lies in the range from 10 μ

m to 1,000 μ

m.

14. Device according to claim 13, wherein a thickness of the foil element is selected in such a way that the foil element has a flexibility, wherein the foil thickness is particularly around 100 μ

m.

15. Device according to claim 14, wherein during the forming process, the foil element is formed with a thicker outer area, particularly in the form of a frame, which increases the mechanical stability of the foil element.

24. Device according to claim 1, wherein the foil element is made of an optically transparent plastic made of organic polymers, such as polymethyl methacrylate, polystyrene, polycarbonate, PEG and polyolefins, or from copolymers, such as COC.

5. Device for optical detection of substances in a liquid or gaseous medium, with a substrate with molecules for detecting the substances that are to be detected, said molecules being immobilised at a surface of the substrate or in the substrate and to which the substances that are to be detected can essentially be selectively bound, wherein light waves can be coupled into the substrate and can be guided through it, wherein the substrate is a foil element made of a transparent material in which a coupling structure for coupling the light waves is integrally formed and in which the coupled light waves can be guided and comprising a flow cell for the medium to be examined, which forms a measurement area with the surface of the foil element, wherein the coupling structure is arranged in the area covered by the flow cell.

6. Device according to claim 5, wherein the molecules for detecting the substances that are to be detected are probes made of biological and/or biochemical molecules, such as antibody molecules and/or DNA molecules and/or DNA single strands and/or RNA molecules and/or RNA single strands, which are immobilised at the surface of the foil element or in the foil element.

16. Device according to claim 5, wherein a polymer cartridge into which the foil element is integrated, wherein this polymer cartridge has an injection port for the medium that is to be examined, reagent containers, fluid canals for transporting the medium and reagents, and devices for moving the medium and the reagents.

23. Device according to claim 6, comprising focusing optics with which optical characteristics, particularly fluorescence characteristics or colours, of substances or labels bound at the surface or in the foil element can be measured.

25. Device according to claim 23, wherein the foil element is made of a glass that is manufactured by hot stamping.

17. Device for optical detection of substances in a liquid or gaseous medium, with a substrate with molecules for detecting the substances that are to be detected, said molecules being immobilised at a surface of the substrate or in the substrate and to which the substances that are to be detected can essentially be selectively bound, wherein light waves can be coupled into the substrate and can be guided through it, wherein the substrate is a foil element made of a transparent material in which a coupling structure for coupling the light waves is integrally formed and in which the coupled light waves can be guided and comprising excitation optics for producing light waves, particularly for exciting a label used for optical detection, such as a fluorescent dye, or for producing a colour change at the surface or in the foil element depending on the medium to be examined.

18. Device according to claim 17, comprising a device for changing a relative position of excitation optics to the coupling structure, with which a coupling angle can be selected in such a way that it roughly corresponds to the total reflection angle, which results with the refractive index of the medium adjacent to the foil element.

19. Device according to claim 18, comprising a decoupling structure formed into the foil element, wherein this decoupling structure is for decoupling the light waves and is formed at the surface of the foil element during the forming step of the foil element in one step, together with the formation of the foil element itself.

20. Device according to claim 19, wherein the decoupling structure is a refractive optical element, such as a prism or a grating or a structure with a trapezoidal or rectangular cross-section, or that the decoupling structure is a diffractive optical element.

21. Device according to claim 20, wherein a detector is arranged in the beam path downstream of the decoupling structure in the beam path, wherein the light waves decoupled from the decoupling structure can be detected by this detector, particularly for optimising the beam position and/or for determining the scattered light of the coupled light waves.

22. Device according to one of the claim 21, wherein the detector for detection of an intensity of the light waves is provided at the decoupling structure for determining absorption of the light waves guided in the foil element and their change.

26. Method for manufacturing a substrate for molecules for the detection of substances in a gaseous or liquid medium, wherein the substances that are to be detected can largely be selectively bound to the probes, wherein the substrate is manufactured as a foil from a transparent material by pressing, rolling, casting or hardening a liquid medium in a mould in such a way that both the surface and a coupling structure for coupling light waves are formed in one manufacturing step.

27. Method according to claim 26, wherein plastic foils are used as the base materials for the substrate, wherein these base materials are processed with a mould at a raised temperature and wherein metal elements processed particularly with micro-millers or silicon wafers with structures introduced by means of anisotropic etching or rolling are used as moulds.

28. Method according to claim 26, wherein the substrate is manufactured by casting, particularly by injection moulding.

29. Method according to claim 28, wherein the hardening process is produced in a mould by means of UV radiation.