Detection of biochemical interactions on a biosensor using tunable filters and tunable lasers

• US 20040223881A1
• Filed: 05/08/2003
• Published: 11/11/2004
• Est. Priority Date: 05/08/2003
• Status: Active Grant

• Current Assignee: X-Body Incorporated (Bristol-Myers Squibb Company), Regents of the University of California (University of California)
• Original Assignee: Sru Biosystems Incorporated
• Inventors: Li, Peter Y., Cunningham, Brian T., Mateus, Carlos, Chang-Hasnain, Constance
• Granted Patent: US 7,497,992 B2
• Time in Patent Office: Days
• US Class Current: 422/82.05
• CPC Class Codes: G01N 21/39 using tunable lasers
• CPC Class Codes: G01N 21/45 using interferometric methods; using Schlieren methods
• CPC Class Codes: G01N 21/75 Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated systems in which material is burnt in a flame or plasma G01N21/72, G01N21/73
• CPC Class Codes: G01N 21/7743 the reagent-coated grating coupling light in or out of the waveguide
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

An apparatus and method for detection of peak wavelength values of colorimetric resonant optical biosensors using tunable filters and tunable lasers is provided. Biomolecular interactions may be detected on a biosensor by directing collimated white light towards a surface of the biosensor. Molecular binding on the surface of the biosensor is indicated by a shift in the peak wavelength value of reflected or transmitted light from the biosensor, while an increase in the wavelength corresponds to an increase in molecular absorption. A tunable laser light source may generate the collimated white light and a tunable filter may receive the reflected or transmitted light and pass the light to a photodiode sensor. The photodiode sensor then quantifies an amount of the light reflected or transmitted through the tunable filter as a function of the tuning voltage of the tunable filter.

Claims

1. A measuring apparatus for detecting a biochemical interaction on a biosensor, the measuring apparatus comprising:

a light source for generating collimated white light and directing the collimated white light towards a surface of the biosensor; and

a tunable filter operable to receive light transmitted through the biosensor and to pass a narrow band of light having wavelengths substantially centered at a passband wavelength and to reflect substantially all other wavelengths, wherein the passband wavelength is adjusted according to a tuning voltage of the tunable filter.

2. The invention of claim 1, wherein the tunable filter is a micro-electro-mechanical (MEM) cantilever device.

3. The invention of claim 1, wherein the tunable filter includes a vertical cavity surface emitting laser (VCSEL).

4. The invention of claim 1, wherein the light source is an LED.

5. The invention of claim 1, wherein the light source is a tunable laser.

6. The invention of claim 5, wherein the tunable laser is a vertical cavity surface emitting laser (VCSEL).

7. The invention of claim 1, wherein the biosensor is a calorimetric resonant optical biosensor.

8. The invention of claim 1, wherein the passband wavelength is adjustable over a wavelength range that includes a biosensor resonant wavelength.

9. The invention of claim 1, wherein the tuning voltage is adjusted as a function of time, so as to sweep the passband wavelength.

10. The invention of claim 1, further comprising a photodiode sensor positioned to receive the narrow band of light having wavelengths substantially centered at the passband wavelength from the tunable filter.

11. The invention of claim 10, wherein the tunable filter includes the photodiode sensor.

12. The invention of claim 10, wherein an output of the photodiode sensor quantifies an amount of the light transmitted through the tunable filter as a function of the tuning voltage of the tunable filter.

13. The invention of claim 1, further comprising a plurality of tunable filters, wherein each tunable filter measures light transmitted through a respective region of the biosensor.

14. The invention of claim 13, wherein the plurality of tunable filters are arranged in a linear array.

23. The invention of claim ]5, further comprising a biosensor readout interface.

15. A measuring apparatus for detecting a biochemical interaction on a biosensor, the measuring apparatus comprising:

a tunable laser light source for generating light having a tunable laser wavelength and for directing the light towards a surface of the biosensor, wherein the tunable laser wavelength is tuned by adjusting a tuning voltage; and

a photodiode detector operable to receive light transmitted through the biosensor and to detect a broad band of wavelengths encompassing a wavelength passband, wherein an output of the photodiode detector quantifies an amount of the light transmitted through the biosensor as a function of the tuning voltage.

16. The invention of claim 15, wherein the tuning voltage adjusts the tunable laser wavelength over a range of wavelength that encompasses a biosensor resonant wavelength.

17. The invention of claim 15, wherein the biosensor is illuminated at normal incidence by the tunable laser light source.

18. The invention of claim 15, wherein the tunable laser light source is a vertical cavity surface emitting laser (VCSEL).

19. The invention of claim 15, wherein the photodiode detector detects a minimum in intensity of the light transmitted through the biosensor as a function of wavelength.

20. The invention of claim 15, wherein the photodiode detector detects a wavelength of peak reflected intensity of the light transmitted through the biosensor.

21. The invention of claim 15, further comprising a plurality of tunable laser light sources, wherein where each tunable laser light source illuminates a respective region on the biosensor'"'"'s surface.

22. The invention of claim 15, wherein the biosensor is a calorimetric resonant optical biosensor.

24. An apparatus for detecting a maximum wavelength of reflected light, the apparatus comprising:

a light source for generating collimated white light;

a power splitter for directing the collimated white light towards a surface of a sensor; and

a tunable detector that receives light reflected by the sensor and measures a radiation spectrum of the light reflected from the sensor, wherein the tunable detector filters a narrow band of light having wavelengths substantially centered at a passband wavelength from the light reflected by the sensor, where the passband wavelength is adjusted according to a tuning voltage of the tunable detector.

25. The invention of claim 24, wherein the tunable detector has a micro-electro-mechanical (MEM) cantilever device.

26. The invention of claim 24, wherein the tunable detector includes a vertical cavity surface emitting laser (VCSEL).

27. The invention of claim 24, wherein the light source is an LED.

28. The invention of claim 24, further comprising an optical fiber probe positioned to receive the collimated white light from the power splitter and to direct the collimated white light towards the surface of the sensor.

29. The invention of claim 28, wherein the optical fiber probe receives the light reflected by the sensor and directs the light reflected by the sensor to the tunable detector.

30. The invention of claim 24, further comprising a collimation device positioned to receive the collimated white light from the power splitter and to direct the collimated white light towards the surface of the sensor.

31. The invention of claim 24, wherein the sensor is a biosensor.

32. An apparatus for detecting a maximum wavelength of reflected light, the apparatus comprising:

a tunable laser light source for generating a tunable single wavelength of light, wherein the tunable laser light source is tuned by adjusting a tuning voltage;

an optical circulator for directing the tunable single wavelength of light towards a surface of a sensor; and

a photodiode detector operable to receive light reflected from the biosensor and to detect a broad band of wavelengths encompassing a wavelength passband, wherein an output of the photodiode detector quantifies an amount of the light reflected from the biosensor as a function of the tuning voltage.

33. The invention of claim 32, wherein the sensor is a biosensor.

34. The invention of claim 32, wherein the tunable laser light source is a vertical cavity surface emitting laser (VCSEL).

35. The invention of claim 32, wherein a peak reflecting wavelength of the light reflected form the biosensor is determined by varying the tunable single wavelength of light emitted by the tunable laser light source.

36. The invention of claim 32, wherein as the tunable laser light source is tuned, only a resonance wavelength of the sensor is reflected from the sensor.

37. The invention of claim 32, further comprising a collimation device positioned to receive the single wavelength of light from the optical circulator and to direct the single wavelength of light towards the surface of the sensor.

38. The invention of claim 37, further comprising a beam expansion device positioned to receive the single wavelength of light from the collimation device and to direct the single wavelength of light towards the surface of the sensor.