Electrophoresis units are compossed by a power source with a voltimeter and voltage regulator, an electrophoresis tank that holds the electrophoresis buffer, an anode and a cathode connected with the power source, a glass plate that holds the gel and is submerged into the electrophoresis buffer, and a comb which is used to make the sample wells in the agar before it solidifies.
Voltage supplied is regulated by the power source. Current flowing between the anode and the cathode establish an electrical field in the electrophoresis tank and in the gel, which will be used for separating compounds according to their charge (proteins) or size (DNA). See step by step instructions for electrophoresis. Agarose gels and in acrylamide gels.