I helped with a BioLab at the Louisville Science Center that was teaching some high school students about DNA.
They learned about DNA as the basic building blocks of life and then how to use a pipette. They then loaded polarized dye into wells in a gel pack in this tray. The case was closed up and then 125 V DC was applied for about 15 minutes.
Here is one of the trays powered up and processing two of the four groups samples.
Here are the finished product of the four groups. Each sample was given two columns and there were three samples A, B, and C. A and C are the same and they paths match.