Monolithic capillary electrophoretic device

A method of fabricating a monolithic capillary electrophoretic device for separating molecular species, the method comprising:

• depositing a sacrificial structure of amorphous silicon upon a substrate;
• covering the sacrificial structure with a first insulating material;
• providing at least one opening in the covering insulating material;
• introducing an etchant via the opening to remove the sacrificial structure to form a buried channel having a first end and a second end;
• and
• depositing at least two electrodes at different locations along the channel such that upon filling of the channel with a liquid matrix containing at least one ion species, and application of a voltage across the channel via the electrodes induces the ion species to migrate along the channel at selected migration velocities.

A monolithic capillary electrophoretic device for separating molecules in a liquid sample based on electrophoretic mobility, the device comprising:

• a buried channel formed upon a semiconductor wafer to serve as a container for a matrix liquid, and surrounded by an insulating material;
• at least a first electrode and a second electrode, located at a first and a second site, respectively, along the channel;
• drive means for applying a voltage between the first and second electrodes;
• introduction means for introducing a liquid sample into the channel at a location between the first and second electrode sites;
• and
• at least one gate electrode for applying a voltage across the insulating material surrounding the channel, thereby repelling ions away from the walls of the channel during migration of the charged species;
• whereby upon application of the voltage by the drive means, ions in the sample of one charge species are attracted to the first electrode and oppositely charged molecular species are attracted to the second electrode.

A monolithic capillary electrophoretic device for separating molecules in a liquid sample based on electrophoretic mobility, the device comprising:

• a buried channel formed upon a semiconductor wafer to serve as a container for a matrix liquid, and surrounded by an insulating material, wherein the length of the channel ranges between about 100 .mu.m and about 2000 .mu.m;
• at least a first electrode and a second electrode, located at a first and a second site, respectively, along the channel;
• drive means for applying a voltage between the first and second electrodes;
• and
• introduction means for introducing a liquid sample into the channel at a location between the first and second electrode sites;
• whereby upon application of the voltage by the drive means, ions in the sample of one charge species are attracted to the first electrode and oppositely charged molecular species are attracted to the second electrode.

A monolithic capillary electrophoretic device for separating molecules in a liquid sample based on electrophoretic mobility, the device comprising:

• a buried channel formed upon a semiconductor wafer to serve as a container for a matrix liquid, and surrounded by an insulating material, wherein the dimensions of the channel range between about 1 .mu.m and about 15 .mu.m wide, and between about 10 nm and about 1 .mu.m thick;
• at least a first electrode and a second electrode, located at a first and a second site, respectively, along the channel;
• drive means for applying a voltage between the first and second electrodes;
• and
• introduction means for introducing a liquid sample into the channel at a location between the first and second electrode sites;
• whereby upon application of the voltage by the drive means, ions in the sample of one charge species are attracted to the first electrode and oppositely charged molecular species are attracted to the second electrode.