Thermal cycling apparatus

• US 20090275113A1
• Filed: 12/15/2008
• Published: 11/05/2009
• Est. Priority Date: 05/17/2006
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: GOODWIN, David, JOHNSTON, Matthew, WALKER, Christopher I., SCHERER, Axel, MALTEZOS, George
• Granted Patent: US 8,003,370 B2
• Time in Patent Office: Days
• US Class Current: 435/286.100
• CPC Class Codes: B01L 2200/143 Quality control, feedback systems
• CPC Class Codes: B01L 2200/147 Employing temperature sensors
• CPC Class Codes: B01L 2300/0829 Multi-well plates; Microtitration plates
• CPC Class Codes: B01L 2300/0838 Capillaries
• CPC Class Codes: B01L 2300/12 Specific details about materials
• CPC Class Codes: B01L 2300/168 Specific optical properties, e.g. reflective coatings
• CPC Class Codes: B01L 2300/1822 using Peltier elements
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2300/185 using a liquid as fluid
• CPC Class Codes: B01L 2300/1861 using radiation
• CPC Class Codes: B01L 3/50851 specially adapted for heating or cooling samples laboratory heating apparatus B01L7/00; incubators C12M
• CPC Class Codes: B01L 3/50853 with covers or lids
• 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: B01L 7/54 using spatial temperature gradients
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters

Abstract

This invention provides an apparatus for providing heating and cooling of samples in sample vessels having uniform temperature profiles. The apparatus can be used for performing PCR, and real time PCR in particular, with control and uniformity. The system employs a heat block containing a liquid composition to efficiently transfer heat to and from reaction vessels.

Claims

1. An apparatus comprising:

a heat block with an upper surface comprising;

i. one or more wells in the upper surface adapted to mate with one or more sample vessels,

ii. a reservoir to contain a liquid wherein the liquid is in thermal contact with the one or more wells;

iii. a stirring element in contact with the liquid for circulating the liquid within the reservoir; and

iv. a heating element in thermal contact with the liquid.

2. The apparatus of claim 1 further comprising a cooling element in thermal contact with the liquid.

3. The apparatus of claim 1 further comprising an optical assembly having a light source and an optical detector, wherein the optical assembly is positioned such that light from the light source is directed into the sample vessels, and light from the sample vessels is detected by the detector.

4. The apparatus of claim 1 wherein the liquid comprises an oil.

5. The apparatus of claim 1 wherein the reservoir in the heat block comprises a closed system.

6. The apparatus of claim 5 wherein the liquid is sealed within in the reservoir.

7. The apparatus of claim 1 wherein the stirring element comprises a stir bar.

8. The apparatus of claim 1 wherein the stirring element comprises more than one stir bar.

9. The apparatus of claim 7 wherein the stir bar is a horizontal stir bar.

10. The apparatus of claim 7 wherein the stir bar is a fan shaped stir bar.

11. The apparatus of claim 7 wherein the stir bar has multiple projections.

12. The apparatus of claim 7 wherein the stir bar is magnetically responsive.

13. The apparatus of claim 7 wherein the stir bar is mechanically connected to a motor.

14. The apparatus of claim 1 wherein the plate has 6, 12, 16, 24, 48, 96, or 384 sample vessels.

15. The apparatus of claim 2 wherein the heating element and the cooling element are Peltier devices.

16. The apparatus of claim 2 wherein the heating element is a resistive heater and the cooling element is a Peltier device.

17. The apparatus of claim 2 wherein the heating element and the cooling element are the same element.

18. The apparatus of claim 17 wherein the same element is Peltier device.

19. The apparatus of claim 3 wherein said optical assembly comprises a PIN photodiode, a CCD imager, a CMOS imager, a line scanner, a photodiode, a phototransistor, a photomultiplier or an avalanche photodiode.

20. The apparatus of claim 3 wherein the light source comprises one or more LEDs, laser diodes, vertical cavity surface emitting lasers (VCSELs), vertical external cavity surface emitting lasers (VECSELs), or diode pumped solid state (DPSS) lasers.

21. The apparatus of claim 3 wherein the optical detector comprises a plurality of optical detectors, wherein at least one optical detector corresponds to each sample vessel in the sample plate.

22. The apparatus of claim 3 further comprising a control assembly which controls the heating element, the cooling element, the light source and the detector.

23. The apparatus of claim 22 wherein the control assembly comprises a programmable computer programmed to automatically process samples, run multiple temperature cycles, obtain measurements, digitize measurements into data and convert data into charts or graphs.

24. The apparatus of claim 23 wherein the multiple temperature cycles correspond to multiple cycles of nucleic acid amplification.

25. The apparatus of claim 24 wherein the nucleic acid amplification comprises real time PCR.

26. A heat block for uniformly heating and cooling multiple sample vessels within a sample plate comprising:

a. a receptacle barrier having a receptacle barrier top surface wherein the receptacle barrier top surface comprises wells which correspond to the sample vessels within the sample plate such that when the plate mates with the receptacle barrier, the sample vessels are in thermal contact with the wells; and

b. a base plate, wherein the heat block comprises a liquid reservoir having a top and a bottom and containing a liquid;

wherein the receptacle barrier comprises the top of the liquid reservoir, and the base plate comprises the bottom of the liquid reservoir, such that when the sample plate is mated with the receptacle barrier, the liquid is in thermal contact with the sample vessels; and

wherein the liquid reservoir comprises a stirring element for circulating the liquid within the liquid reservoir.

27. The heat block of claim 26 further comprising a heating element in thermal contact with the liquid in the liquid reservoir.

28. The heat block of claim 27 further comprising a cooling element in thermal contact with the liquid in the liquid reservoir.

29. The heat block of claim 28 wherein the heating element and the cooling element are the same device.

30. The heat block of claim 29 wherein the same device comprise a Peltier device.

31. The heat block of claim 30 wherein the Peltier device is in physical contact with the base plate.

32. The heat block of claim 27 wherein the heating element comprises a resistive heater.

33. The heat block of claim 26 wherein the liquid comprises an oil.

34. The heat block of claim 26 wherein the sample vessels have a maximum volume of about 50 μ

L.

35. The heat block of claim 26 wherein the plate comprises 6, 12, 16, 24, 48, 96, or 384 sample vessels.

36. The heat block of claim 26 comprising a closed system.

37. The heat block of claim 36 wherein the liquid is sealed in the heat block during the heating and cooling of the sample vessels.

38. The apparatus of claim 26 wherein the stirring element comprises a stir bar.

39. The apparatus of claim 26 wherein the stirring element comprises more than one stir bar.

40. The apparatus of claim 38 wherein the stir bar is a horizontal stir bar.

41. The apparatus of claim 38 wherein the stir bar is a fan shaped stir bar.

42. The apparatus of claim 38 wherein the stir bar has multiple projections.

43. The apparatus of claim 38 wherein the stir bar is magnetically coupled to a motor.

44. The apparatus of claim 38 wherein the stir bar mechanically connected to a motor.

45. The apparatus of claim 39 wherein the stir bars are magnetically coupled to one or more motors.

46. The apparatus of claim 39 wherein the stir bars are mechanically connected to one or more motors.

47. The apparatus of claim 26 wherein the base plate comprises a metal plate.

48. The apparatus of claim 45 wherein the base plate comprises aluminum or copper.