Microfluidic flow manipulation device

• US 7,658,536 B2
• Filed: 04/21/2008
• Issued: 02/09/2010
• Est. Priority Date: 09/19/2001
• Status: Active Grant

• Current Assignee: The United States of America As Represented By The Secretary of Commerce
• Original Assignee: THE GOVERNMENT OF THE UNITED STATES OF AMERICA, AS REPRESENTED BY THE SECRETARY OF COMMERCE
• Inventors: Ross, David J., Johnson, Timothy J., Locascio, Laurie E.
• Primary Examiner(s): Sorkin; David L
• Application Number:
  US12/106,990
• Publication Number:
  US 20080190773A1
• Time in Patent Office: 659 Days
• Field of Search: 366DIG 1-DIG 4, 366336-341, 366/181.5, 137/896
• US Class Current: 366/181.5
• CPC Class Codes: G05D 7/0694 by action on throttling means or flow sources of very small size, e.g. microfluidics microvalves F16K99/0001; microstructural devices per se B81B
• CPC Class Codes: Y10S 366/03 Micromixers: variable geometry from the pathway influences mixing/agitation of non-laminar fluid flow
• CPC Class Codes: Y10T 137/0318 Processes
• CPC Class Codes: Y10T 137/2224 Structure of body of device
• CPC Class Codes: Y10T 137/87652 With means to promote mixing or combining of plural fluids

Abstract

Disclosed is an apparatus and method for the mixing of two microfluidic channels wherein several wells are oriented diagonally across the width of a mixing channel. The device effectively mixes the confluent streams with electrokinetic flow, and to a lesser degree, with pressure driven flow. The device and method may be further adapted to split a pair of confluent streams into two or more streams of equal or non-equal concentrations of reactants. Further, under electrokinetic flow, the surfaces of said wells may be specially coated so that the differing electroosmotic mobility between the surfaces of the wells and the surfaces of the channel may increase the mixing efficiency. The device and method are applicable to the steady state mixing as well as the dynamic application of mixing a plug of reagent with a confluent stream.

Claims

1. A mixer of laminar microfluidic streams propelled by electrokinetic flow comprising:

a first inlet channel;

a second inlet channel;

a mixing channel starting at the confluence of said first inlet channel and said second inlet channel; and

a plurality of substantially straight unconnected wells disposed in said mixing channel, said wells being obliquely oriented substantially across the width of said mixing channel, said wells being greater in depth than in width, said wells having well surfaces that effect electroosmotic mobility such that electroosmotic mobility at said well surfaces is higher than electroosmotic mobility at other surfaces of said mixing channel.

2. The mixer of claim 1 wherein alternating wells are configured perpendicular to each other.

3. The mixer of claim 1 wherein said wells are configured parallel to each other.

4. A splitter of a substantially laminar microfluidic stream comprising:

a splitting channel coupled to at least two inlet ports and at least one outlet port in which said substantially laminar microfluidic stream has an axis of flow; and

a plurality of substantially straight unconnected wells disposed in said splitting channel, said wells being oriented substantially across the width of said channel and diagonal to said axis of flow, said wells being greater in depth than in width, said wells having well surfaces that effect electroosmotic mobility such that electroosmotic mobility at said well surfaces is higher than electroosmotic mobility at other surfaces of said splitting channel.

5. The splitter of claim 4 wherein alternating wells are configured perpendicular to each other.

6. The splitter of claim 4 wherein said wells are configured parallel to each other.

7. The splitter of claim 4 wherein said microfluidic streams are propelled by pressure.

8. The splitter of claim 4 wherein said microfluidic streams are propelled by electroosmosis.

9. The splitter of claim 4 wherein said microfluidic streams are propelled by electrokinetics.

10. A mixer of laminar microfluidic streams propelled by electrokinetic flow comprising:

a first inlet channel;

a second inlet channel;

a mixing channel starting at the confluence of said first inlet channel and said second inlet channel; and

a plurality of substantially straight unconnected wells disposed in said mixing channel, said wells being obliquely oriented substantially across the width of said mixing channel, said wells having well surfaces that effect electroosmotic mobility such that electroosmotic mobility at said well surfaces is higher than electroosmotic mobility at other surfaces of said mixing channel.

11. A splitter of a substantially laminar microfluidic stream comprising:

a splitting channel coupled to at least two inlet ports and at least one outlet port in which said substantially laminar microfluidic stream has an axis of flow; and

a plurality of substantially straight unconnected wells disposed in said splitting channel, said wells being oriented substantially across the width of said channel and diagonal to said axis of flow, said wells having well surfaces that effect electroosmotic mobility such that electroosmotic mobility at said well surfaces is higher than electroosmotic mobility at other surfaces of said splitting channel.