ELECTROWETTING-BASED VALVING AND PUMPING SYSTEMS
The present teachings relate to microfluidic valves and pumping systems, which may be suitable for controlling and facilitating liquid flow. Electrodes are disposed proximately to volumes containing a liquid. The liquid flow can be facilitated by electrowetting forces. Processes for controlling the flow of liquids, as well as for pumping liquids, are also disclosed.
1 . A valving system comprising:
a channel fluidly coupled to a first reservoir and a second reservoir;
a volume in fluid communication with said channel
a fluidic obstruction configured to be included in the volume,
wherein the fluidic obstruction is configured to move from a first position to a second position based on a net force created by an electrical potential difference at an interface between an electrode and the fluidic obstruction, and
wherein the fluidic obstruction is configured to block the channel to prevent fluid communication between the first and second reservoir when the fluidic obstruction is in the second position;
a power source electrically coupled to at least two electrodes, the power source being configured to provide the electrical potential difference at the interface between the electrode and the fluidic obstruction sufficient to provide a net force to move the fluidic obstruction within the volume.
2 . The system according to claim 1 further comprising a second channel, wherein said second channel is at least one of vented to the atmosphere, fluidly coupled to said volume, fluidly coupled to said first reservoir, fluidly coupled to said second reservoir, fluidly coupled to another fluidic component, and blind.
3 . The system according to claim 1 , wherein the at least two electrodes have adjoining edges.
4 . The system according to claim 1 , wherein at least a portion of the channel is hydrophilic.
5 . The system according to claim 1 , wherein at least a portion of the channel is hydrophobic.
6 . The system according to claim 1 , further comprising at least one additional electrode in said channel.
7 . The system according to claim 2 , further comprising an electrode proximate to at least a portion of said second channel.
8 . The system according to claim 2 , further comprising a third channel.
9 . The system according to claim 8 , wherein said third channel is fluidly coupled to said first channel and at least one of the atmosphere, said first reservoir, said second reservoir, and an additional fluidic component.
10 . The system according to claim 1 , wherein at least one dimension of at least a portion of said volume is trapezoidal in shape.
11 . The system according to claim 8 , wherein at least one dimension of at least a portion of said volume is trapezoidal in shape.
12 . The system according to claim 1 , wherein a photoconductive material is electrically coupled to at least one of said first and second electrodes.
13 - 28 . (canceled)
29 . A method of valving comprising:
providing an electrical potential difference at an interface between an electrode and a fluidic obstruction sufficient to provide a net force to move the fluidic obstruction within a volume to a second position from a first position,
wherein the volume is in fluid communication with a channel,
wherein the channel is fluidly coupled to a first reservoir and a second reservoir, and
wherein the fluidic obstruction configured to: be included in the volume, to move from the first position to the second position based on a net force created by an electrical potential difference at an interface between an electrode and the fluidic obstruction, and to block the channel to prevent fluid communication between the first and second reservoir when the fluidic obstruction is in the second position.
30 . The method of claim 29 , further comprising:
providing a second electrical potential difference at an interface between the electrode and the fluidic obstruction sufficient to provide a net force to move the fluidic obstruction within a volume to back to the first position from the second position.