Systems, devices, and methods for isotachophoresis

The fluidic device of the preceding claim, further comprising:

• (a) a substrate having a first face and a second face, wherein said first face comprises a plurality of reservoirs including said first loading reservoir and said one or more pneumatic ports and said second face comprises a plurality of channels including said first channel, wherein said plurality of reservoirs communicate with said plurality of channels via through holes in said substrate;
• (b) a layer of material covering said second face, thereby forming closed channels;
• and
• (c) a cover covering at least part of said first face and comprising through holes that communicate with ports in said first face through gaskets.

A fluidic device comprising a fluidic channel and disposed in said fluidic channel a capillary barrier that restricts flow of a liquid in said fluidic channel, wherein said capillary barrier comprises:

• a ramp protruding from a surface of said fluidic channel at a first angle;
• a plateau area;
• and
• a cliff area extending from said plateau area to said surface of said fluidic channel and wherein said cliff area intersects with said surface at a second angle that is substantially steeper than said first angle.

A fluidic device comprising a fluidic channel and disposed in said fluidic channel a capillary barrier that restricts flow of a liquid in said fluidic channel, wherein said capillary barrier comprises:

• (a) a first ramp protruding from a surface of said fluidic channel at a first angle that is less than 80 degrees;
• (b) a plateau area;
• and
• (c) a second ramp extending from said plateau area to said surface of said fluidic channel and wherein said second ramp intersects with said surface at a second angle that is less than 80 degrees.

A fluidic device comprising one or more branched fluidic circuits, wherein each of said branched fluidic circuits comprises an isotachophoresis (“ITP”) branch and an elution branch in communication with said ITP branch, wherein:

• (a) said ITP branch comprises a trailing electrolyte buffer reservoir, a sample channel, a leading electrolyte buffer channel, a first leading buffer electrolyte reservoir and a second leading electrolyte buffer reservoir, all in communication with each other, wherein:
• (i) said sample channel is separated from said trailing electrolyte reservoir by a first cliff capillary barrier and from said leading electrolyte buffer channel by a second cliff capillary barrier,
• (ii) said leading electrolyte reservoir is separated from said second leading electrolyte reservoir by a first plateau capillary barrier;
• and
• (b) said elution branch comprises an elution channel, a first elution buffer reservoir and a second elution buffer reservoir, all in communication with each other, wherein:
• (i) said first elution buffer reservoir is separated from said second elution buffer reservoir a second plateau capillary barrier, and
• (ii) said leading electrolyte buffer channel is separated from at least part of said elution channel by a third plateau capillary barrier.

A device for performing vertical isotachophoresis, the device comprising:

• one or more cylindrical columns comprising an interior channel defined by an inner wall of the cylindrical column, each cylindrical column comprising:
• a first stage comprising a first gel plug disposed at a first location within the interior channel and a first space disposed within the interior channel between the first gel plug and an upper end of the cylindrical column;
• a second stage comprising a second gel plug disposed at a second location within the interior channel, the second location being located below the first location and oriented in line with gravity, and a second space disposed within the interior channel between the first gel plug and the second gel plug;
• and
• a third stage comprising a third gel plug disposed at a third location within the interior channel, the third location being located below the second location and oriented in line with gravity, and a third space disposed within the interior channel between the second gel plug and the third gel plug.