Gel electrophoresis can be conducted in either a horizontal or vertical orientatio

Procedure:

Gel electrophoresis apparatus . an agarose gel is placed in this buffer-filled box and an electrical field is applied via the power supply to the rear. The negative terminal is at the far end (black wire), so DNA migrates toward the positively charged anode (red wire)

Horizontal Gel Electrophoresis

In horizontal gel electrophoresis, a gel is cast in a horizontal orientation and submerged in running buffer within the gel box. The gel box is divided into two compartments, with agarose gel separating the two. As previously stated, an anode is located at one end, while a cathode is located at the other. The ionic running buffer allows for a charge gradient to be created when a current is applied. In addition, the buffer serves to cool the gel, which heats up as a charge is applied. The running buffer is often recirculated to prevent a pH gradient from forming.

Since the two compartments of a horizontal gel system are connected through the running buffer, it is not possible to utilize horizontal systems with a discontinuous buffer system. Additionally, acrylamide cannot be used for horizontal systems because gels are cast in a tray which is exposed to atmospheric oxygen. Oxygen inhibits the polymerization of acrylamide, and thus, interferes with the creation of the gel. The ease-of-use of a horizontal system makes this an ideal choice for most DNA and RNA applications. Electrophoresis gel with fluorescing dye illuminating bands