Multi-channel optical detection system

• US 20020109844A1
• Filed: 04/08/2002
• Published: 08/15/2002
• Est. Priority Date: 03/02/1998
• Status: Active Grant

• Current Assignee: Cepheid (Danaher Corporation)
• Original Assignee: Cepheid (Danaher Corporation)
• Inventors: Herbert, Raymond T., Chang, Ronald, Petersen, Kurt E., Northrup, M. Allen, McMillan, William A., Christel, Lee A., Young, Steven J., Kovacs, Gregory T.A., Dority, Douglas B., Kintz, Gregory J.
• Granted Patent: US 6,940,598 B2
• Time in Patent Office: Days
• US Class Current: 356/417
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01L 2300/042 Caps; Plugs
• CPC Class Codes: B01L 2300/0809 rectangular shaped
• CPC Class Codes: B01L 2300/0858 Side walls
• CPC Class Codes: B01L 2300/168 Specific optical properties, e.g. reflective coatings
• CPC Class Codes: B01L 2300/1805 Conductive heating, heat from thermostatted solids is conducted to receptacles, e.g. heating plates, blocks
• CPC Class Codes: B01L 3/508 rigid containers not provided for above
• CPC Class Codes: B01L 3/5082 Test tubes per se
• CPC Class Codes: B01L 7/52 with provision for submitting samples to a predetermined sequence of different temperatures, e.g. for treating nucleic acid samples amplification or hybridisation processes per se C12Q1/68; controlling sequential reactions for synthesis B01J19/0046
• CPC Class Codes: F28D 2021/0077 for tempering, e.g. with cooling or heating circuits for temperature control of elements
• CPC Class Codes: F28F 21/04 of ceramic; of concrete; of natural stone
• CPC Class Codes: F28F 2280/10 Movable elements, e.g. being pivotable
• CPC Class Codes: F28F 3/12 Elements constructed in the shape of a hollow panel, e.g. with channels F28D1/02, F28D1/03 take precedence
• CPC Class Codes: G01N 2035/00326 Analysers with modular structure
• CPC Class Codes: G01N 21/0303 Optical path conditioning in cuvettes, e.g. windows; adapted optical elements or systems; path modifying or adjustment G01N21/031 - G01N21/15 take precedence
• CPC Class Codes: G01N 21/0332 with temperature control control of temperature G05D23/00; cryostats F17C3/08

Abstract

An apparatus for thermally controlling and optically interrogating a reaction mixture includes a vessel [2] having a chamber [10] for holding the mixture. The apparatus also includes a heat-exchanging module [37] having a pair of opposing thermal plates [34A, 34B] for receiving the vessel [2] between them and for heating/and or cooling the mixture contained in the vessel. The module [37] also includes optical excitation and detection assemblies [46,48] positioned to optically interrogate the mixture. The excitation assembly [46] includes multiple light sources [100] and a set of filters for sequentially illuminating labeled analytes in the mixture with excitation beams in multiple excitation wavelength ranges. The detection assembly [48] includes multiple detectors [102] and a second set of filters for detecting light emitted from the chamber [10] in multiple emission wavelength ranges. The optics assemblies [46,48] thus provide a multi-channel system for detecting a plurality of different target analytes in the mixture.

Claims

1. An apparatus for thermally controlling and optically interrogating a reaction mixture, the apparatus comprising:

a) a reaction vessel having a chamber for holding the mixture, wherein the vessel includes first and second optically transmissive walls;

b) opposing plates positioned to receive the vessel between them;

c) at least one heating element coupled to at least one of the plates for heating the reaction mixture; and

d) first and second optics assemblies positioned such that when the vessel is placed between the plates, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls, respectively;

the first optics assembly comprising;

i) a first housing having a first optical window;

ii) at least two light sources for transmitting excitation beams to the reaction mixture through the first window; and

iii) a first set of filters for filtering the excitation beams such that each of the beams transmitted to the reaction mixture has a substantially distinct excitation wavelength range, wherein the light sources and the first set of filters are rigidly fixed in the first housing;

and the second optics assembly comprising;

i) a second housing having a second optical window for receiving light emitted from the chamber;

ii) at least two detectors for detecting the emitted light; and

iii) a second set of filters for separating the emitted light into at least two emission wavelength ranges and for directing the emitted light in each of the emission wavelength ranges to a respective one of the detectors, wherein the detectors and the second set of filters are rigidly fixed in the second housing.

2. The apparatus of claim 1, wherein the first optics assembly includes at least four light sources arranged with the first set of filters for transmitting the excitation beams in at least four excitation wavelength ranges, and wherein the second optics assembly includes at least four detectors arranged with the second set of filters for detecting the emitted light in at least four emission wavelength ranges.

3. The apparatus of claim 1, further comprising an adjustable power source for supplying a variable amount of power to the light sources.

4. The apparatus of claim 1, further comprising electronics for receiving signals from the detectors and for adjusting the gain or offset of the signals.

5. The apparatus of claim 1, further comprising a controller for controlling the operation of the optics assemblies.

6. The apparatus of claim 5, wherein the controller is programmed to convert output signals from the detectors into values representative of the concentrations of individual dyes in the reaction mixture using a calibration matrix.

7. The apparatus of claim 5, wherein at least one of the excitation wavelength ranges overlaps one of the emission wavelength ranges, and wherein the controller is programmed to receive a calibration signal from the detector receiving light in the overlapped emission wavelength range and to adjust subsequent output signals received from the detectors in dependence upon the calibration signal.

8. The apparatus of claim 1, wherein a portion of the vessel defining the chamber includes retro-reflective walls for reflecting light emitted from the reaction mixture.

9. The apparatus of claim 8, wherein the chamber is substantially diamond-shaped, and wherein the optically transmissive walls define the bottom portion of the chamber and the retro-reflective walls define the top portion of the chamber.

10. The apparatus of claim 1, wherein the first and second optically transmissive walls of the vessel are angularly offset from each other by about 90°

.

11. The apparatus of claim 10, wherein the longitudinal axes of the optics assemblies are angularly offset from each other at an angle of about 90°

, and wherein the assemblies are positioned such that when the vessel is placed between the plates, the longitudinal axis of the first optics assembly is substantially orthogonal to the first optically transmissive wall and the longitudinal axis of the second optics assembly is substantially orthogonal to the second optically transmissive wall.

12. The apparatus of claim 1, wherein each of the sides of the chamber has a length in the range of 1 to 15 mm, and wherein the chamber has a thickness in the range of 0.5 to 5 mm.

13. The apparatus of claim 1, wherein each of the sides of the chamber has a length in the range of 5 to 12 mm, and wherein the chamber has a thickness in the range of 0.5 to 2 mm.

14. The apparatus of claim 1, wherein the ratio of the length of each side of the chamber to the thickness of the chamber is at least 2:

1.

15. The apparatus of claim 1, wherein the ratio of the length of each side of the chamber to the thickness of the chamber is at least 5:

1.

17. The system of claim 16, wherein the first optics assembly of each module includes at least four light sources arranged with the first set of filters for transmitting the excitation beams in at least four excitation wavelength ranges, and wherein the second optics assembly of each module includes at least four detectors arranged with the second set of filters for detecting the emitted light in at least four emission wavelength ranges.

18. The system of claim 16, further comprising a computer programmed to control the processing electronics in the base instrument.

19. The system of claim 16, wherein each of the heat-exchanging modules further includes a cooling system for cooling one of the reaction mixtures.

16. A system for independently thermally controlling and optically interrogating a plurality of reaction mixtures, the system comprising:

a) a plurality of reaction vessels, wherein each of the vessels has a reaction chamber for holding one of the mixtures, and wherein each of the vessels includes first and second optically transmissive walls defining a portion of its chamber;

b) a corresponding plurality of heat-exchanging modules for receiving the vessels, wherein each of the modules comprises;

i) opposing plates positioned to receive one of the vessels between them;

ii) at least one heating element coupled to at least one of the plates for heating the reaction mixture contained in the vessel; and

iii) first and second optics assemblies positioned such that when the vessel is placed between the plates, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls of the vessel, respectively;

the first optics assembly comprising;

a first housing having a first optical window;

at least two light sources for transmitting excitation beams to the reaction mixture through the first window; and

a first set of filters for filtering the excitation beams such that each of the beams transmitted to the reaction mixture has a substantially distinct excitation wavelength range, wherein the light sources and the first set of filters are rigidly fixed in the first housing;

and the second optics assembly comprising;

i) a second housing having a second optical window for receiving light emitted from the vessel;

ii) at least two detectors for detecting the emitted light; and

iii) a second set of filters for separating the emitted light into at least two emission wavelength ranges and for directing the emitted light in each of the emission wavelength ranges to a respective one of the detectors, wherein the detectors and the second set of filters are rigidly fixed in the second housing; and

c) a base instrument for receiving the heat-exchanging modules, wherein the base instrument includes processing electronics for controlling the operation of each module.

20. An apparatus for optically interrogating a reaction mixture contained in a reaction vessel having first and second optically transmissive walls, the apparatus comprising:

a) a slot for receiving the vessel; and

b) first and second optics assemblies positioned such that when the vessel is placed in the slot, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls of the vessel, respectively;

wherein the first optics assembly comprises;

i) a first housing having a first optical window;

ii) at least two light sources for transmitting excitation beams to the reaction mixture through the first window; and

iii) a first set of filters for filtering the excitation beams such that each of the beams transmitted to the reaction mixture has a substantially distinct excitation wavelength range, wherein the light sources and the first set of filters are rigidly fixed in the first housing;

and wherein the second optics assembly comprises;

i) a second housing having a second optical window for receiving light emitted from the mixture;

ii) at least two detectors for detecting the emitted light; and

iii) a second set of filters for separating the emitted light into at least two emission wavelength ranges and for directing the emitted light in each of the emission wavelength ranges to a respective one of the detectors, wherein the detectors and the second set of filters are rigidly fixed in the second housing.

21. The apparatus of claim 20, wherein the first optics assembly includes at least four light sources arranged with the first set of filters for transmitting the excitation beams in at least four excitation wavelength ranges, and wherein the second optics assembly includes at least four detectors arranged with the second set of filters for detecting the emitted light in at least four emission wavelength ranges.

22. The apparatus of claim 20, further comprising an adjustable power source for supplying a variable amount of power to the light sources.

23. The apparatus of claim 20, further comprising electronics for receiving signals from the detectors and for adjusting the gain or offset of the signals.

24. The apparatus of claim 20, further comprising a controller for controlling the operation of the optics assemblies.

25. The apparatus of claim 24, wherein the controller is programmed to convert output signals from the detectors into values representative of the concentrations of individual dyes in the reaction mixture using a calibration matrix.

26. The apparatus of claim 24, wherein at least one of the excitation wavelength ranges overlaps one of the emission wavelength ranges, and wherein the controller is programmed to receive a calibration signal from the detector receiving light in the overlapped emission wavelength range and to adjust subsequent output signals received from the detectors in dependence upon the calibration signal.

27. The apparatus of claim 20, wherein the first and second optically transmissive walls of the vessel are angularly offset from each other at an angle of about 90°

, the longitudinal axes of the optics assemblies are angularly offset from each other at an angle of about 90°

, and the assemblies are positioned such that when the vessel is placed in the slot, the longitudinal axis of the first optics assembly is substantially orthogonal to the first optically transmissive wall and the longitudinal axis of the second optics assembly is substantially orthogonal to the second optically transmissive wall.

28. The apparatus of claim 20, wherein the first optics assembly further comprises a first lens positioned in the first optical window for focusing the excitation beams, and wherein the second optics assembly further comprises a second lens positioned in the second optical window for collimating the light emitted from the chamber.

30. The apparatus of claim 29, wherein the first optics assembly further includes a third detector rigidly fixed in the first housing for receiving light emitted from the chamber in a third emission wavelength range different than the first and second emission wavelength ranges, and wherein the first set of filters includes at least one filter for filtering the emitted light outside of the third emission wavelength range and for directing the emitted light in the third emission wavelength range to the third detector.

31. The apparatus of claim 30, wherein the second optics assembly further includes a fourth detector rigidly fixed in the second housing for receiving light emitted from the chamber in a fourth emission wavelength range different than the first, second, and third emission wavelength ranges, and wherein the second set of filters includes at least one filter for filtering the emitted light outside of the fourth emission wavelength range and for directing the emitted light in the fourth emission wavelength range to the fourth detector.

32. The apparatus of claim 29, wherein a portion of the vessel defining the chamber includes retro-reflective walls for reflecting light emitted from the reaction mixture.

33. The apparatus of claim 32, wherein the chamber is substantially diamond-shaped, and wherein the optically transmissive walls define the bottom portion of the chamber and the retro-reflective walls define the top portion of the chamber.

34. The apparatus of claim 29, wherein the first and second optically transmissive walls of the vessel are angularly offset from each other by an angle of about 90°

.

35. The apparatus of claim 34, wherein the longitudinal axes of the optics assemblies are angularly offset from each other by an angle of about 90°

, and wherein the assemblies are positioned such that when the vessel is placed between the plates, the longitudinal axis of the first optics assembly is substantially orthogonal to the first optically transmissive wall and the longitudinal axis of the second optics assembly is substantially orthogonal to the second optically transmissive wall.

36. The apparatus of claim 29, wherein each of the sides of the chamber has a length in the range of 1 to 15 mm, and wherein the chamber has a thickness in the range of 0.5 to 5 mm.

37. The apparatus of claim 29, wherein each of the sides of the chamber has a length in the range of 5 to 12 mm, and wherein the chamber has a thickness in the range of 0.5 to 2 mm.

38. The apparatus of claim 29, wherein the ratio of the length of each side of the chamber to the thickness of the chamber is at least 2:

1.

39. The apparatus of claim 29, wherein the ratio of the length of each side of the chamber to the thickness of the chamber is at least 5:

1.

29. An apparatus for thermally controlling and optically interrogating a reaction mixture, the apparatus comprising:

a) a reaction vessel having a chamber for holding the mixture, wherein the vessel includes first and second optically transmissive walls;

b) opposing plates positioned to receive the vessel between them;

c) at least one heating element coupled to at least one of the plates for heating the reaction mixture; and

d) first and second optics assemblies positioned such that when the vessel is placed between the plates, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls, respectively;

the first optics assembly comprising;

i) a first housing having a first optical window;

ii) a first light source for transmitting a first excitation beam to the reaction mixture through the first window;

iii) a first detector for receiving light emitted from the chamber through the first window; and

iv) a first set of filters arranged in the first housing for filtering portions of the first excitation beam outside of a first excitation wavelength range, for filtering portions of the emitted light outside of a first emission wavelength range, and for directing the emitted light in the first emission wavelength range to the first detector, wherein the first light source, the first set of filters, and the first detector are rigidly fixed in the first housing;

and the second optics assembly comprising;

i) a second housing having a second optical window;

ii) a second light source for transmitting a second excitation beam to the reaction mixture through the second window;

iii) a second detector for receiving light emitted from the chamber through the second window; and

iv) a second set of filters arranged in the second housing for filtering portions of the second excitation beam outside of a second excitation wavelength range different than the first excitation wavelength range, for filtering portions of the emitted light outside of a second emission wavelength range different than the first emission wavelength range, and for directing the emitted light in the second emission wavelength range to the second detector, wherein the second light source, the second set of filters, and the second detector are rigidly fixed in the second housing.

40. A system for independently thermally controlling and optically interrogating a plurality of reaction mixtures, the system comprising:

a) a plurality of reaction vessels, wherein each of the vessels has a reaction chamber for holding one of the mixtures, and wherein each of the vessels includes first and second optically transmissive walls defining a portion of its chamber;

b) a corresponding plurality of heat-exchanging modules for receiving the vessels, wherein each of the modules comprises;

i) opposing plates positioned to receive one of the vessels between them;

ii) at least one heating element coupled to at least one of the plates for heating the reaction mixture contained in the vessel; and

iii) first and second optics assemblies positioned such that when the vessel is placed between the plates, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls of the vessel, respectively;

the first optics assembly comprising;

a first housing having a first optical window;

a first light source for transmitting a first excitation beam to the reaction mixture contained in the vessel through the first window;

a first detector for receiving light emitted from the chamber through the first window; and

a first set of filters arranged in the first housing for filtering portions of the first excitation beam outside of a first excitation wavelength range, for filtering portions of the emitted light outside of a first emission wavelength range, and for directing the emitted light in the first emission wavelength range to the first detector, wherein the first light source, the first set of filters, and the first detector are rigidly fixed in the first housing;

and the second optics assembly comprising;

a second housing having a second optical window;

a second light source for transmitting a second excitation beam to the reaction mixture through the second window;

a second detector for receiving light emitted from the chamber through the second window; and

a second set of filters arranged in the second housing for filtering portions of the second excitation beam outside of a second excitation wavelength range different than the first excitation wavelength range, for filtering portions of the emitted light outside of a second emission wavelength range different than the first emission wavelength range, and for directing the emitted light in the second emission wavelength range to the second detector, wherein the second light source, the second set of filters, and the second detector are rigidly fixed in the second housing; and

c) a base instrument for receiving the heat-exchanging modules, wherein the base instrument includes processing electronics for independently controlling the operation of each module.

41. The system of claim 40, wherein the first optics assembly of each heat-exchanging module further includes a third detector rigidly fixed in the first housing for receiving light emitted from the chamber in a third emission wavelength range different than the first and second emission wavelength ranges, and wherein the first set of filters includes at least one filter for filtering the emitted light outside of the third emission wavelength range and for directing the emitted light in the third emission wavelength range to the third detector.

42. The system of claim 41, wherein the second optics assembly of each heat-exchanging module further includes a fourth detector rigidly fixed in the second housing for receiving light emitted from the chamber in a fourth emission wavelength range different than the first, second, and third emission wavelength ranges, and wherein the second set of filters includes at least one filter for filtering the emitted light outside of the fourth emission wavelength range and for directing the emitted light in the fourth emission wavelength range to the fourth detector.

43. The system of claim 40, further comprising a computer programmed to control the processing electronics in the base instrument.

44. An apparatus for optically interrogating a reaction mixture contained in a reaction vessel, wherein the vessel includes first and second optically transmissive walls, the apparatus comprising:

a) a slot for receiving the vessel; and

b) first and second optics assemblies positioned such that when the vessel is placed in the slot, the first and second optics assemblies are in optical communication with the first and second optically transmissive walls of the vessel, respectively;

wherein the first optics assembly comprises;

i) a first housing having a first optical window;

ii) a first light source for transmitting a first excitation beam to the reaction mixture through the first window;

iii) a first detector for receiving light emitted from the chamber through the first window; and

iv) a first set of filters arranged in the first housing for filtering portions of the first excitation beam outside of a first excitation wavelength range, for filtering portions of the emitted light outside of a first emission wavelength range, and for directing the emitted light in the first emission wavelength range to the first detector, wherein the first light source, the first set of filters, and the first detector are rigidly fixed in the first housing;

and wherein the second optics assembly comprises;

i) a second housing having a second optical window;

ii) a second light source for transmitting a second excitation beam to the reaction mixture through the second window;

iii) a second detector for receiving light emitted from the chamber through the second window; and

iv) a second set of filters arranged in the second housing for filtering portions of the second excitation beam outside of a second excitation wavelength range different than the first excitation wavelength range, for filtering portions of the emitted light outside of a second emission wavelength range different than the first emission wavelength range, and for directing the emitted light in the second emission wavelength range to the second detector, wherein the second light source, the second set of filters, and the second detector are rigidly fixed in the second housing.

45. The apparatus of claim 44, wherein the first optics assembly further includes a third detector rigidly fixed in the first housing for receiving light emitted from the chamber in a third emission wavelength range different than the first and second emission wavelength ranges, and wherein the first set of filters includes at least one filter for filtering the emitted light outside of the third emission wavelength range and for directing the emitted light in the third emission wavelength range to the third detector.

46. The apparatus of claim 45, wherein the second optics assembly further includes a fourth detector rigidly fixed in the second housing for receiving light emitted from the chamber in a fourth emission wavelength range different than the first, second, and third emission wavelength ranges, and wherein the second set of filters includes at least one filter for filtering the emitted light outside of the fourth emission wavelength range and for directing the emitted light in the fourth emission wavelength range to the fourth detector.

47. The apparatus of claim 44, further comprising an adjustable power source for supplying a variable amount of power to each of the light sources.

48. The apparatus of claim 44, further comprising electronics for receiving signals from the detectors and for adjusting the gain or offset of the signals.

49. The apparatus of claim 44, further comprising a controller for controlling the operation of the optics assemblies.

50. The apparatus of claim 44, wherein the first and second optically transmissive walls of the vessel are angularly offset from each other at an angle of about 90°

, the longitudinal axes of the optics assemblies are angularly offset from each other at an angle of about 90°

, and the assemblies are positioned such that when the vessel is placed in the slot, the longitudinal axis of the first optics assembly is substantially orthogonal to the first optically transmissive wall and the longitudinal axis of the second optics assembly is substantially orthogonal to the second optically transmissive wall.