HEAT-REDUCTION METHODS AND SYSTEMS RELATED TO MICROFLUIDIC DEVICES

• US 20120183454A1
• Filed: 02/06/2012
• Published: 07/19/2012
• Est. Priority Date: 02/14/2001
• Status: Active Grant

• Current Assignee: HandyLab Incorporated (Becton Dickinson & Co)
• Original Assignee: HandyLab Incorporated (Becton Dickinson & Co)
• Inventors: Handique, Kalyan
• Granted Patent: US 8,440,149 B2
• Time in Patent Office: Days
• US Class Current: 422/502
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/1822 using Peltier elements
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2300/1883 using thermal insulation
• CPC Class Codes: B01L 2300/1894 Cooling means; Cryo cooling
• CPC Class Codes: B01L 2400/0442 thermal energy, e.g. vaporisation, bubble jet
• CPC Class Codes: B01L 3/5027 by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 7/00 Heating or cooling apparatus autoclaves B01J3/04; Heat insulating devices
• CPC Class Codes: C12Q 1/6806 Preparing nucleic acids for analysis, e.g. for polymerase chain reaction [PCR] assay C12Q1/6804 takes precedence
• CPC Class Codes: H05B 3/22 non-flexible
• CPC Class Codes: H05K 3/10 in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base

Abstract

The present relates to a system and method for preventing or reducing unwanted heat in a microfluidic of the device while generating heat in selected regions of the device. Current can be supplied to a heating element through electric leads that are designed so that the current density in the leads is substantially lower than the current density in the heating element. Unwanted heat in the microfluidic complex can be reduced by thermally isolating the electric leads from the microfluidic complex by, for example, running each lead directly away from the microfluidic complex. Unwanted heat can be removed from selected regions of the microfluidic complex using one or more cooling devices.

Claims

1. An integrated microfluidic processing system comprising a microfluidic device, the device comprising:

a first side;

a second side;

a microfluidic complex comprising a plurality of flow channels, wherein the microfluidic complex is located proximate to the first side of the microfluidic device and distant from the second side of the microfluidic device;

a heating element configured to heat a region of the microfluidic complex, wherein the heating element is located relatively more distant from the first side of the microfluidic device and more proximate to the second side of the microfluidic device than the microfluidic complex; and

at least one conductive lead for supplying electrical current from a current source to the heating element, wherein a portion of the lead extends from a first position within the microfluidic device that is similarly spaced with respect to the first and second sides of the microfluidic device as is the heating element to a second position within the microfluidic device located relatively more distant from the first side of the microfluidic device and more proximate to the second side of the microfluidic device than the heating element.

13. The integrated microfluidic processing system of claim 1, wherein the microfluidic device comprises a first substrate and a second substrate.

14. The integrated microfluidic processing system of claim 13, wherein the heating element is located in the second substrate.

15. The integrated microfluidic processing system of claim 13, wherein the microfluidic complex is defined in part by the first substrate.

16. The integrated microfluidic processing system of claim 13, wherein the microfluidic complex is located between the first and second substrates.

17. The integrated microfluidic processing system of claim 13, wherein the first and second substrate are in thermal communication.

18. The integrated microfluidic processing system of claim 13, wherein one of the flow channels in the microfluidic complex comprises a reaction chamber.

19. The integrated microfluidic processing system of claim 18, wherein the heating element is configured to heat the reaction chamber.

20. The integrated microfluidic processing system of claim 13, wherein the microfluidic complex comprises a valve.

21. The integrated microfluidic processing system of claim 20, wherein the valve is thermally actuatable.

22. The integrated microfluidic processing system of claim 20, wherein the heating element is configured to heat the valve.

23. The integrated microfluidic processing system of claim 1, further comprising a thermally isolating layer.

24. The integrated microfluidic processing system of claim 23, wherein the thermally is located between the first position of the lead and the second position of the lead.

25. The integrated microfluidic processing system of claim 24, wherein the lead passes through an opening in the thermally isolating layer.

2-12. -12. (canceled)

26. An integrated microfluidic processing system comprising a microfluidic device, the microfluidic device comprising:

a first side;

a second side;

a microfluidic complex comprising a plurality of flow channels, wherein the microfluidic complex is located proximate to the first side of the microfluidic device and distant from the second side of the microfluidic device;

a heating element configured to heat a region of the microfluidic complex, wherein the heating element is located relatively more distant from the first side of the microfluidic device and more proximate to the second side of the microfluidic device than the microfluidic complex; and

at least one conductive lead for supplying electrical current from a current source to the heating element, wherein the lead has a lower current density that the heating element.

27. The integrated microfluidic processing system of claim 26, wherein the heating element comprises a resistive material having a first cross-sectional dimension and a second cross-sectional dimension.

28. The integrated microfluidic processing system of claim 27, wherein the lead has a first crossOsectional dimension and a second cross-sectional dimension.

29. The integrated microfluidic processing system of claim 28, wherein the first cross-sectional dimension of the lead is larger than the first cross-sectional dimension of the heating element.

30. The integrated microfluidic processing system of claim 29, wherein the second cross-sectional dimension of the lead is larger than the second cross-sectional dimension of the heating element.

31. The integrated microfluidic processing system of claim 26, wherein the microfluidic device comprises a first substrate and a second substrate.

32. The integrated microfluidic processing system of claim 31, wherein the heating element is located in the second substrate.

33. The integrated microfluidic processing system of claim 31, wherein the microfluidic complex is defined in part by the first substrate.

34. The integrated microfluidic processing system of claim 31, wherein the microfluidic complex is located between the first and second substrates.

35. The integrated microfluidic processing system of claim 31, wherein the first and second substrate are in thermal communication.

36. The integrated microfluidic processing system of claim 31, wherein one of the flow channels in the microfluidic complex comprises a reaction chamber.

37. The integrated microfluidic processing system of claim 36, wherein the heating element is configured to heat the reaction chamber.

38. The integrated microfluidic processing system of claim 31, wherein the microfluidic complex comprises a valve.

39. The integrated microfluidic processing system of claim 38, wherein the valve is thermally actuatable.

40. The integrated microfluidic processing system of claim 38, wherein the heating element is configured to heat the valve.