Analysis of molecular interactions on and/or in thin layers

• US 8,174,708 B2
• Filed: 08/09/2008
• Issued: 05/08/2012
• Est. Priority Date: 08/09/2007
• Status: Active Grant

• Current Assignee: Biocopy Holding AG
• Original Assignee: Biametrics Maken und Rechte GmbH
• Inventors: Gauglitz, Guenter, Proll, Guenther, Proell, Florian, Steinle, Lutz, Schubert, Markus
• Primary Examiner(s): Connolly, Patrick J
• Application Number:
  US12/672,535
• Publication Number:
  US 20110026034A1
• Time in Patent Office: 1,368 Days
• Field of Search: 356/503, 356/504, 356/630, 356/632
• US Class Current: 356/630
• CPC Class Codes: G01N 21/45 using interferometric methods; using Schlieren methods
• CPC Class Codes: G01N 21/8422 Investigating thin films, e.g. matrix isolation method
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: G01N 33/551 the carrier being inorganic

Abstract

The invention relates to a carrier for a thin layer and a method for the analysis of molecular interactions on and/or in such a thin layer. A thin layer disposed on a carrier is illuminated with electromagnetic radiation from at least one radiation source and a reflected radiation part on boundary surfaces of the thin layer is detected by means of an optoelectronic converter that converts the detected radiation into a frequency- and intensity-dependant photocurrent. A reading voltage is applied to the optoelectronic converter. By changing the reading voltage, the spectral sensitivity of the optoelectronic converter is varied such that a substantially constant photocurrent is obtained. Alternatively or in addition to varying the spectral sensitivity by changing the reading voltage, the reflected radiation part is detected with an optoelectronic converter that is designed as a sensor layer in the carrier. The carrier is particularly characterized in that it comprises a substrate on which at least one sensor layer with optoelectronic properties is disposed.

Claims

1. A method of analyzing molecular interactions on and/or in a thin layer on a support, comprising the steps of

illuminating the thin layer using electromagnetic radiation from at least one radiation source,

detecting radiation reflected on outer faces of the thin layer by at least one optoelectronic sensor that converts the radiation detected into a frequency and intensity dependent photocurrent,

applying a reading voltage to the optoelectronic sensor for measuring the photocurrent, and

varying the spectral sensitivity of the optoelectronic sensor by changing the reading voltage such that a substantially constant photocurrent is obtained.

2. The method according to claim 1, wherein parameters are derived from the reading voltage that characterize the interactions to be analyzed on or in the thin layer.

3. The method according to claim 1 wherein the thin layer on the support is turned away from the incident radiation.

4. The method according to claim 1 wherein the molecular interactions to be analyzed are physical, chemical, or biochemical reactions, detection, binding, or agglomeration events.

5. The method according to claim 1 wherein the thin layer is illuminated with electromagnetic radiation having a spectral bandwidth of between 5 nm and 50 nm.

6. The method according to claim 1 wherein the optoelectronic sensor comprises a photodiode of a p-i-n, a p-n, or a n-i-p-i-n type, or a Schottky diode.

7. The method of analyzing molecular interactions on or in a thin layer according to claim 1 wherein the reflected radiation part is detected using an optoelectronic sensor that is a sensor layer in the support.

8. The method according to claim 1 wherein the wavelength of the electromagnetic radiation is varied during illumination, in particular by actuation of at least two different spectrally overlapping radiation sources in opposite directions.

9. The method according to claim 8, wherein the variation of the wavelength of the electromagnetic radiation is carried out synchronously or oppositely to the change of the reading voltage with regard to the change of the photocurrent resulting from it.

10. A support for a thin layer for analyzing molecular interactions on or in the thin layer, in particular in a method according to claim 1, wherein the support has multiple layers, in the order of a protective layer of silicon dioxide, a highly refracting layer of tantalum pentoxide or niobium pentoxide, and a substrate of glass, plastic, or metal on which the at least one sensor layer having optoelectronic properties is provided.

11. The support according to claim 10, wherein the at least one sensor layer has at least one amorphous, nanocrystalline, or polycrystalline, in particular silicon-based semiconductor material having optoelectronic properties, the at least one sensor layer comprising a preferably continuous layer of the at least one semiconductor material or at least one layer subdivided into sections from the at least one semiconductor material.

12. The support according to claim 11, wherein the at least one, preferably continuous or subdivided layer of the at least one semiconductor material is a p-i-n, a p-n, or a n-i-p-i-n type, or a Schottky diode.

13. The support according to claim 11 wherein the at least one, layer of the at least one semiconductor material has a sequence of sublayers comprising a varying optical bandgap and having a layer sequence of p-i₁-i₂-n, p-i₁-i₂-i₃-n, n-i₁-i₂-p, or n-i₁-p-i₂-i₃-p.

14. The support according to claim 13, wherein at least one of the sublayers is doped with carbon or germanium.

15. The support according to claim 11 wherein the at least one layer of the at least one semiconductor material has a sequence of sublayers of:

a p-conducting Si;

H layer

a self-conducting Si;

H layer

a self-conducting Si;

H layer

a n-conducting Si;

H layer

where Si;

H is a thin layer semiconductor on the basis of silicon that is amorphous or crystalline, or undoped or doped or not blended, or blended with carbon, nitrogen, or germanium.

16. The support according to claim 10 wherein the at least one sensor layer has at least one contact layer that preferably directly adjoins the at least one layer of the at least one semiconductor material.

17. The support according to claim 16, wherein the at least one contact layer consists of ZnO, ITO (indium tin oxide) or of metal.

18. The support according to claims 16 wherein the at least one sensor layer has a contact layer and a layer subdivided into sections from the at least one semiconductor material directing adjoining it, the contact layer overlapping the adjoining layer subdivided into sections on at least one side.

19. The support according to claim 16 wherein the at least one sensor layer has a layer sequence of:

a contact layer, preferably of zinc oxide,

a preferably continuous or subdivided layer of the at least one semiconductor material having optoelectronic properties,

a metal contact layer, preferably of aluminum.