(12) United States Patent ao) Patent No.: Us 7,658,536 B2
Johnson et al. (45) Date of Patent: Feb. 9,2010
(54) MICROFLUIDIC FLOW MANIPULATION DEVICE
(75) Inventors: Timothy J. Johnson, Charlestown, MA (US); David J. Ross, Silver Spring, MD (US); Laurie E. Locascio, North Potomac, MD (US)
(73) Assignee: The United States of America as represented by the Secretary of Commerce, Washington, DC (US)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
(21) Appl.No.: 12/106,990
(22) Filed: Apr. 21, 2008
(65) Prior Publication Data
US 2008/0190773 Al Aug. 14, 2008
Related U.S. Application Data
(60) Continuation of application No. 11/131,145, filed on May 16, 2005, now abandoned, which is a division of application No. 10/188,664, filed on Jul. 1, 2002, now Pat. No. 6,907,895.
(60) Provisional application No. 60/323,509, filed on Sep. 19, 2001.
(58) Field of Classification Search ... 366/DIG. 1 DIG.
4,336-341, 181.5; 137/896 See application file for complete search history.
(56) References Cited
U.S. PATENT DOCUMENTS
3,226,036 A * 12/1965 Grain 239/400
3,788,557 A * 1/1974 Breunsbach 239/401
5,811,062 A * 9/1998 Wegengetal 422/129
5,900,130 A * 5/1999 Benvegnuetal 204/453
6,632,655 Bl * 10/2003 Mehtaetal 506/14
2004/0262223 Al * 12/2004 Strooketal 210/634
* cited by examiner
Primary Examiner—David L Sorkin
(74) Attorney, Agent, or Firm—William W. Cochran; Christopher P. Whitham; Cochran Freund & Young LLC
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 nonequal 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.
11 Claims, 20 Drawing Sheets