Patent ID: 7008521

Claim:
A device having a flowpath therein for electrokinetically driven liquid flow therealong, the device comprising first and second members, first and second grooves in the first member, a plurality of third grooves in the second member, with each third groove having respective first and second ends, a first connecting groove in the second member, the first ends of the third grooves opening into the first connecting groove, a second connecting groove in the second member, the second ends of the third grooves opening into the second connecting groove, wherein the first member has a first member surface and the second member has a second member surface, the first and second member surfaces are connected to one another, the first member surface closes the third grooves to form a plurality of third channels, the first member surface closes the first and second connecting grooves to form first and second connecting channels, the second member surface closes the first and second grooves to form first and second channels, liquid flows along the flowpath, passing sequentially through the first channel, from the first channel into the first connecting channel, from the first connecting channel into the plurality of third channels, in parallel through the third channels, from the third channels into the second connecting channel, and from the second connecting channel into the second channel, and each third channel has a respective cross-sectional area smaller than cross-sectional areas of the first and second channels so that the third channels collectively resist hydrostatically driven liquid flow along the flowpath.