We began the experiment by sealing the ends of the gel-casting tray with tape, and inserting the comb. We placed the tray out of the way to make sure that it was not disturbed. We poured about 6mm of agarose solution into the casting tray. The gel covered only about 1/2 the height of the combs teeth. We removed large bubbles with the tip of a transfer pipet while the gel was still a liquid. While waiting about ten minutes for the gel to solidify, we made sure not to move the casting tray. After the gel solidified we unsealed the ends of the casting tray. We placed the tray in the gel box, so that the comb was at the negative end. We poured 250ml of tris-borate-EDTA (TBE) buffer into the gel box to a level that covered the entire surface of the gel. We gently removed the comb, making sure not to rip the wells. The sample wells left by the comb were completely submerged. We carefully used the pipet to load the DNA into the wells. We expelled any air in the pipet before we loaded it into the gel. We placed the pipet through the buffer solution and slowly expelled the mixture. We then closed the top of the electrophoresis chamber and connected the electrical leads black to black and red to red to the power supply. We turned on the power supply and set the voltage to 120 volts. We turned the electric current off after 60 minutes. We then removed the casting tray and placed it into the Carolina BLU™ solution to be stained. We took the gel out of the staining tray and then measured the HindIII fragment and the EcoRI fragment in centimeters from the front edge of the well to the front edge of each band. As well as the control enzyme. Photographs were then taken as data records....
