Digital microfluidics devices and methods of using them

A cartridge for a digital microfluidics (DMF) apparatus, the cartridge having a bottom and a top, the cartridge comprising:

• a sheet of dielectric material having a first side and a second side, the first side forming an exposed bottom surface on the bottom of the cartridge;
• a first hydrophobic layer on the second side of the sheet of dielectric material;
• a top plate having a first side and a second side and a thickness therebetween;
• a ground electrode on the first side of the top plate;
• a second hydrophobic layer on the first side of the top plate covering the ground electrode;
• an air gap separating the first hydrophobic layer and the second hydrophobic layer;
• a microfluidics channel formed in or on the second side of the top plate, wherein the microfluidics channel extends along the second side of the top plate;
• an opening between the microfluidics channel and the air gap;
• and
• a cover covering the microfluidics channel, wherein the cover includes one or more access ports for accessing the microfluidics channel.

A cartridge for a digital microfluidics (DMF) apparatus, the cartridge having a bottom and a top, the cartridge comprising:

• a sheet of dielectric material having a first side and a second side, the first side forming an exposed bottom surface on the bottom of the cartridge;
• a first hydrophobic layer on the second side of the sheet of dielectric material;
• a top plate having first side and a second side and a thickness therebetween;
• a ground electrode on first side of the top plate;
• a second hydrophobic layer on the first side of the top plate covering the ground electrode;
• an air gap separating the first hydrophobic layer and the second hydrophobic layer, wherein the air gap comprises a separation of greater than 500 micrometers;
• a first microfluidics channel and a second microfluidics channel, wherein the first and second microfluidics channels are formed in the second side of the top plate, wherein the first and second microfluidics channels extend along the second side of the top plate;
• a first opening between the first microfluidics channel and the air gap and a second opening between the second microfluidics channel and the air gap, wherein the first and second openings are adjacent to each other within about 2 cm;
• and
• a cover covering the microfluidics channel, wherein the cover includes one or more access ports for accessing the microfluidics channel.