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, wherein said volume is adapted to contain a fluid chosen from a gas bubble and a liquid droplet;
a first electrode proximate to said volume;
a second electrode proximate to said channel, wherein said first and second electrodes are proximate to each other; and
a power source electrically coupled to each electrode, the power source being configured to provide an electrical potential difference at the interface between the electrode and a liquid droplet sufficient to provide a net force to move said droplet.
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 said first and second 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)