Method of pumping fluid through a microfluidic device

• US 8,652,852 B2
• Filed: 10/13/2011
• Issued: 02/18/2014
• Est. Priority Date: 03/12/2007
• Status: Active Grant

• Current Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: Beebe, David J., Warrick, Jay W., Toepke, Michael W., Meyvantsson, Ivar, Walker, Glenn M.
• Primary Examiner(s): Sines, Brian J
• Application Number:
  US13/272,433
• Publication Number:
  US 20120051947A1
• Time in Patent Office: 859 Days
• Field of Search: 422/50, 422/68.1, 422/502, 422/503, 422/504, 422/509, 436/43, 436/180
• US Class Current: 436/180
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0457 passive flow or gravitation
• 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: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: Y10T 137/0357 For producing uniform flow
• CPC Class Codes: Y10T 137/0363 For producing proportionate flow
• CPC Class Codes: Y10T 137/0379 By fluid pressure
• CPC Class Codes: Y10T 137/0396 Involving pressure control
• CPC Class Codes: Y10T 436/11 Automated chemical analysis
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream
• CPC Class Codes: Y10T 436/118339 with formation of a segmented stream
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

A method is provided for pumping fluid through a channel of a microfluidic device. The channel has an input port and an output port. The channel is filled with fluid and a pressure gradient is generated between the fluid at the input port and the fluid at the output port. As a result, fluid flows through the channel towards the output port.

Claims

1. A method of pumping fluid through a channel of a microfluidic device, the channel having a first input port having a cross-sectional area and an output port having a cross-sectional area greater than the cross-sectional area of the first input port, comprising the steps of:

filling the channel with fluid; and

sequentially depositing pumping drops of fluid at the first input port of the channel to generate a pressure gradient between fluid at the input port and fluid at the output port, each of the pumping drops having an effective radius of curvature and the fluid at the first output port having an effective radius of curvature greater than the effective radius of curvature of each pumping drop;

whereby the fluid in the channel flows toward the output port without use of an external device to facilitate the flow of fluid in the channel.

2. The method of claim 1 wherein each of the pumping drops has a radius generally equally to the predetermined radius of the input port of the channel.

3. The method of claim 1 comprising the additional step of varying the flow rate of first pumping drop through the channel.

4. The method of claim 1 wherein the channel has a cross-sectional area and wherein step of the flow rate of first pumping drop through the channel includes the step of reducing the cross-sectional area of at least a portion of the channel.