Microfluidic devices having a reduced number of input and output connections

• US 20050152808A1
• Filed: 09/12/2002
• Published: 07/14/2005
• Est. Priority Date: 09/12/2001
• Status: Active Grant

• Current Assignee: HandyLab Incorporated (Becton, Dickinson & Co)
• Original Assignee: HandyLab Incorporated (Becton, Dickinson & Co)
• Inventors: Ganesan, Karthik
• Granted Patent: US 7,674,431 B2
• Time in Patent Office: Days
• US Class Current: 422/99
• CPC Class Codes: B01L 2200/02 Adapting objects or devices to another
• CPC Class Codes: B01L 2200/14 Process control and prevention of errors
• CPC Class Codes: B01L 2200/147 Employing temperature sensors
• CPC Class Codes: B01L 2300/02 Identification, exchange or storage of information
• CPC Class Codes: B01L 2300/0819 Microarrays; Biochips
• CPC Class Codes: B01L 2300/1827 using resistive heater
• CPC Class Codes: B01L 2400/0442 thermal energy, e.g. vaporisation, bubble jet
• CPC Class Codes: B01L 2400/0677 phase change valves; Meltable, freezing, dissolvable plugs; Destructible barriers
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/50273 characterised by the means or forces applied to move the fluids micropumps F04B19/006, of the membrane type F04B43/043
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 3/502746 characterised by the means for controlling flow resistance, e.g. flow controllers, baffles B01L3/502738 takes precedence
• CPC Class Codes: B01L 7/00 Heating or cooling apparatus autoclaves B01J3/04; Heat insulating devices
• CPC Class Codes: G05D 7/0617 specially adapted for fluid materials
• CPC Class Codes: Y10T 137/0318 Processes
• CPC Class Codes: Y10T 436/12 Condition responsive control
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A system and method for reducing the number of input/output connections required to connect a microfluidic substrate to an external controller for controlling the substrate. In one example, a microfluidic processing device is fabricated on a substrate having a plurality of N independently controllable components, (e.g., a resistive heating elements) each having at least two terminals. The substrate includes a plurality of input/output contacts for connecting the substrate to an external controller, and a plurality of leads for connecting the contacts to the terminals of the components. The leads are arranged to allow the external controller to supply control signals to the terminals of the components via the contacts using substantially fewer contacts than the total number of component terminals. For example, in one embodiment, each lead connects a corresponding contact to a plurality of terminals to allow the controller to supply to signals to the terminals without requiring a separate contact for each terminal. However, to assure that the components can each be controlled independently of the others, the leads are also arranged so that each component'"'"'s terminals are connected to a unique combination of contacts. Thus, the external controller can activate a selected component by supplying control signals to the combination of contacts uniquely associated with that component.

Claims

1. A microfluidic processing device, comprising:

a substrate comprising a plurality of N independently controllable components, each having at least two terminals;

a plurality of input/output contacts for connecting said substrate to an external controller, and a

plurality of leads for connecting said contacts to said terminals, whereby the number of contacts required to independently control said N components is substantially less than the total number of terminals without requiring a separate lead for each said terminal, and wherein said controller can thereby control each said component independently of each other component.

2. The microfluidic device of claim 1 wherein each said lead connects a corresponding contact to a plurality of terminals to allow said controller to provide signals to said terminals without requiring a separate contact for each terminal, and wherein the terminals of each said component are connected to a unique combination of contacts, so that said external controller can thereby control each said component independently of the other components.

3. The microfluidic processing device according to claim 2, wherein the number of contacts is related to the number of said components by the formula, 2{square root}N.

4. The microfluidic processing device according to claim 1, wherein at least a subset of the N components are resistive heating elements.

5. The microfluidic processing device according to claim 1, wherein at least a subset of the N components are resistive sensing elements.

6. The microfluidic processing device of claim 1 wherein at least one of said independently controllable components comprises a plurality of sub-components that are all activated by said external controller using the unique combination of contacts associated with said at least one independently controllable component.

7. The microfluidic device of claim 1, wherein the device includes a plurality of current flow directional elements configured to allow current to flow in essentially only one direction through the components.

8. The microfluidic device of claim 1, wherein the substrate includes a thermally actuated valve and at least one of the N independently controllable components is a heating element in thermal communication with the thermally actuated valve.

9. The microfluidic device of claim 8, wherein the substrate includes a plurality of thermally actuated valves and each component of a subset of the N independently controllable components is a heating element in thermal communication with a respective thermally actuated valve.

10. The microfluidic device of claim 1, wherein the substrate includes a thermally actuated pump comprising a volume of fluid and at least one of the N independently controllable components is a heating element in thermal communication with the volume of fluid, whereby actuation of the heating element heats the fluid and actuates the thermally actuated pump.

11. The microfluidic device of claim 10, wherein the substrate includes a plurality of thermally actuated pumps each comprising a volume of fluid and, wherein each component of a subset of the N independently controllable components is a heating element in thermal communication with the volume of fluid of a respective thermally actuated pump.

12. A method for fabricating a microfluidic processing device comprising:

providing a substrate having a plurality of components each having at least two terminals;

providing a plurality of input/output contacts for connecting said substrate to an external controller; and

providing a plurality of leads for connecting said contacts to said terminals, whereby the number of contacts required to independently control said N components is substantially less than the total number of terminals without requiring a separate lead for each said terminals, and wherein said controller can thereby control each said component independently of each other component.

13. A method according to claim 12, wherein each lead connects a corresponding contact to a plurality of said terminals.

14. A method according to claim 12, wherein the number of contacts is related to the number of said components by the formula, 2{square root}N.

15. A method according to claim 12, wherein the component is a resistive heating element.

16. The method according to claim 12 wherein at least one of said independently controllable components comprises a plurality of sub-components that are all activated by said external controller using the unique combination of contacts associated with said at least one independently controllable component.

17. A method according to claim 12, wherein the component is a resistive sensing element.