Claims
- 1. A microfluidic system comprising:
a body including a microfluidic channel through which a fluid flows; and valve means for inflating a gas phase bubble in said fluid at a location along said channel; wherein said bubble is stationary at said location to restrict flow through said channel.
- 2. The microfluidic system according to claim 1, wherein said channel defines a single flow path at said location.
- 3. The microfluidic system according to claim 1, wherein said valve means includes an anode and a cathode arranged to apply a voltage across said fluid when said anode and cathode are connected to a voltage source, whereby said bubble is inflated electrochemically.
- 4. The microfluidic system according to claim 3, wherein said anode and said cathode are each in contact with said fluid.
- 5. The microfluidic system according to claim 3, wherein said anode and said cathode are respectively arranged on opposite sides of said channel.
- 6. The microfluidic system according to claim 5, wherein said channel includes a feeder portion and a neck portion adjacent to and downstream from said feeder portion, said neck portion having a reduced cross-sectional area relative to said feeder portion, and said anode and said cathode are located along said feeder portion proximate to said neck portion.
- 7. The microfluidic system according to claim 1, wherein said body includes a semiconductor chip.
- 8. The microfluidic system according to claim 7, wherein said valve means includes a voltage source, an anode deposited on said semiconductor chip and connected to said voltage source, and a cathode deposited on said semiconductor chip and connected to said voltage source, said anode and said cathode being arranged to apply a voltage across said fluid.
- 9. A microfluidic system comprising:
a semiconductor chip including a microfluidic channel through which a fluid flows, said channel including a feeder portion and a neck portion adjacent to and downstream from said feeder portion, said neck portion having a reduced cross-sectional area relative to said feeder portion; and an anode and a cathode deposited on said semiconductor chip on opposite sides of said channel at a location along said feeder portion proximate said neck portion.
- 10. The microfluidic system according to claim 9, wherein said anode and said cathode communicate with said channel so as to contact fluid flowing through said channel.
- 11. A method of regulating flow of a fluid through a microfluidic channel, said method comprising the steps of:
inflating a gas phase bubble in said fluid at a location along said channel; and maintaining said bubble at said location along said channel.
- 12. The method according to claim 11, wherein said bubble is maintained at said location by an inner wall of said channel.
- 13. The method according to claim 12, wherein said bubble is inflated electrochemically by applying a voltage across said fluid.
- 14. The method according to claim 13, wherein said applied voltage is chosen based at least in part on an inlet pressure of said fluid.
- 15. A method of temporarily stopping flow of a fluid through a microfluidic channel, said method comprising the steps of:
applying a voltage across said fluid to electrochemically inflate a gas phase bubble in said fluid; maintaining said bubble at a fixed location along said channel; and removing said voltage after a period of time to allow said bubble to deflate.
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/333834 filed Nov. 28, 2001.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] The U.S. government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Grant No. 0201293 awarded by the National Science Foundation.
Provisional Applications (1)
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Number |
Date |
Country |
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60333834 |
Nov 2001 |
US |