Methods and systems for fluid control in microfluidic devices
First Claim
Patent Images
1. A valve for use in a microfluidic system, comprising:
- a substrate defining an upstream channel and a downstream channel joined by a passage, the passage comprising a first surface; and
a thermally responsive substance (TRS) disposed, when the valve is in the closed state, to substantially obstruct the passage, wherein pressure present in the upstream channel urges at least a portion of the TRS against the first surface; and
a reservoir adjacent the passage, wherein, upon an opening motion of the TRS, at least at least a portion of the TRS moves into the reservoir thereby opening the passage.
2 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to a valve for use in a microfluidic system. The valve includes a substrate defining an upstream channel and a downstream channel joined by a passage, wherein the passage comprises a first opposed wall disposed at an angle to a central axis of the upstream channel. A thermally responsive substance (TRS) obstructs the passage. At least a portion of the TRS that obstructs the passage abuts the first opposed wall. Upon the actuation of the heat source in thermal contact with the TRS an opening motion of the TRS opens the passage.
413 Citations
34 Claims
-
1. A valve for use in a microfluidic system, comprising:
-
a substrate defining an upstream channel and a downstream channel joined by a passage, the passage comprising a first surface; and
a thermally responsive substance (TRS) disposed, when the valve is in the closed state, to substantially obstruct the passage, wherein pressure present in the upstream channel urges at least a portion of the TRS against the first surface; and
a reservoir adjacent the passage, wherein, upon an opening motion of the TRS, at least at least a portion of the TRS moves into the reservoir thereby opening the passage. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for producing a valve for a microfluidic system, comprising:
-
providing a first substrate having a first planar surface and a second, different substrate having a first planar surface, a portion of the first planar surface of the first substrate bonded with a portion of the first planar surface of the second substrate, whereby the first and second substrates define, therebetween, a passage that joins an upstream channel and a downstream channel of the microfluidic system, the passage comprising a retaining surface; and
introducing a mass of temperature responsive material (TRS) into the passage, wherein introducing the mass of TRS comprises heating the passage to allow motion of the TRS therein, and wherein, when the valve is in the closed state, pressure in the upstream channel urges the TRS against the retaining surface.
-
-
12. A method for producing a valve for a microfluidic system, the valve being produced in the closed state, comprising:
-
providing a substrate defining a passage that joins an upstream and a downstream channel of the microfluidic system; and
introducing a mass of temperature responsive material (TRS) into a reservoir channel adjacent the passage, wherein capillary action draws the TRS into the passage, and wherein, upon being drawn into the passage, the TRS obstructs the passage and a surface tension of the TRS substantially prevents the TRS in the passage from entering the upstream or downstream channel.
-
-
13. A microfluidic system comprising a valve for providing a passage between an upstream and a downstream channel of the microfluidic system, the [valve] microfluidic system comprising:
-
a first substrate having a first planar surface and a second, different substrate having a first planar surface, a portion of the first planar surface of the first substrate bonded to a portion of the first planar surface of the second substrate, whereby the first and second substrates define, therebetween, at least an upstream channel and a downstream channel joined by a passage; and
a temperature responsive substance (TRS), wherein, at a first temperature, the TRS is disposed to obstruct the passage, and wherein, at a second temperature, at least a portion of the (TRS) enters the downstream channel, thereby opening the passage. - View Dependent Claims (14)
-
-
15. A microfluidic system comprising a valve for providing a passage between upstream and downstream channels of the microfluidic system, comprising:
-
a first substrate having a first planar surface and a second, different substrate having a first planar surface, a portion of the first planar surface of the first substrate bonded to a portion of the first planar surface of the second substrate, whereby the first and second substrates define, therebetween, at least an upstream channel and a downstream channel joined by a passage;
a temperature responsive substance (TRS) configured to substantially obstruct the passage;
a heat source disposed in thermal contact with the (TRS), wherein, upon actuation of the heat source, at least a portion of the (TRS) enters the downstream channel, thereby opening the passage. - View Dependent Claims (16, 17, 18, 19, 20)
-
-
21. A microfluidic system, comprising:
-
a first substrate having a first planar surface and a second substrate having a first planar surface, the first planar surface of the first substrate bonded with the first planar surface of the second substrate, whereby the first and second substrates define, therebetween, a processing chamber, a source channel, and a downstream channel, the source channel joining the processing chamber at a first point and the downstream channel joining the processing chamber at a second point;
a thermally responsive substance (TRS) disposed to obstruct a passage between the processing chamber and downstream channel; and
a heat source in thermal contact with the TRS, wherein, upon actuation of the heat source, at least a portion of the TRS enters the downstream channel, thereby opening the passage.
-
-
22. A valve for use in a microfluidic system, comprising:
-
a thermally responsive substance (TRS) disposed to substantially obstruct the passage, wherein a length of the TRS obstructing the passage is greater than a width of the upstream channel adjacent the passage; and
a heat source in thermal contact with the TRS, wherein, upon actuation of the heat source, at least a portion of the TRS obstructing the passage moves out of the passage, thereby opening the passage. - View Dependent Claims (23, 24, 25, 26)
-
-
27. A valve for use in a microfluidic system, comprising:
-
a substrate defining a first and second channel joined by a passage, the first channel and the passage defining an opening therebetween;
a thermally responsive substance (TRS) disposed to substantially obstruct the passage, wherein a height of the opening is less than a height of the first channel adjacent the opening such that capillary action draws TRS into the passage and a surface tension of the TRS substantially prevents the TRS from entering the first or second channel; and
a heat source in thermal contact with the TRS, wherein, upon actuation of the heat source, an opening motion of the TRS opens the passage. - View Dependent Claims (28, 29, 30, 31)
a reservoir adjacent the passage, a height of the reservoir at a first location being less than a height of the reservoir at a second location, the first location being closer to the passage than the second location.
-
-
31. The valve of claim 30, wherein the reservoir comprises an a port for introducing TRS to the reservoir.
-
32. A microfluidic system, comprising:
-
a first planar substrate and a second, different planar substrate, a first surface of the first substrate and a first surface of the second substrate defining, therebetween, at least an upstream channel and a downstream channel joined by a passage, the passage comprising a first surface; and
a thermally responsive substance (TRS), at least a first portion of the TRS disposed, when the passage is in the closed state, to substantially obstruct the passage, wherein pressure present in the upstream channel urges at least a portion of the first portion of the TRS against the first surface of the passage.
-
-
33. A method for producing a valve for a microfluidic system, the valve being produced in the closed state, comprising:
-
providing a substrate defining a passage that joins an upstream and a downstream channel of the microfluidic system; and
introducing a mass of temperature responsive material (TRS) into a reservoir channel adjacent the passage;
heating at least the reservoir channel and passage, wherein capillary action draws at least a portion of the TRS into the passage thereby obstructing the passage.
-
-
34. A method for producing a valve for a microfluidic system, the valve being produced in the closed state, comprising:
-
providing a substrate defining (1) a passage that joins an upstream and a downstream channel of the microfluidic system and (2) a reservoir joining the passage, wherein a height of the reservoir at a first location is less than a height of the reservoir at a second location, the first location of the reservoir being closer to the passage than the second location;
heating at least the reservoir and passage;
introducing a mass of temperature responsive material (TRS) into the reservoir at least until a portion of the TRS reaches the first location of the reservoir, wherein capillary action draws TRS into the passage thereby obstructing the passage.
-
Specification