Making a Gel

Making a Gel (1% Agarose Gel)

NOTE: Wear gloves!! Ethidium bromide is a mutagen, you don’t want to touch it

1. Weigh 0.5 g of agarose (found on the Chemical Shelves) and put into a 125 mL Erlenmeyer flask (in Cabinet A).

2. Measure 50 mL of 0.5X TBE (in Cabinet A) and pour into the Erlenmeyer flask with the agarose. Swirl the flask to disperse the agarose evenly.

3. Heat for 30 seconds in the microwave, let cool for 10 seconds, then heat for another 10 seconds. Insert a thermometer (found in Drawer A or the drying rack) into the solution, put a KimWipe on top to cover it, and let the agarose solution cool down to 70°C. Periodically swirl the flask to ensure the temperature is even throughout the solution.

4. While waiting, get an electrophoresis tank and gel tray (both found in Drawer A), wipe with a Kimwipe. Carefully put the gel tray in the tank in the casting position with the rubber gaskets touching the tank walls. Verify that the gaskets make a perfect seal with the tank on both sides (are not twisted out of the gel tray).

5. When the agarose temperature is near 70°C, get a 10 µL pipette and ethidium bromide (EtBr, Fridge A). When the temperature is 70°C, add 2 µL of EtBr into the agarose solution. After pipetting the EtBr into the solution, set your pipette to 4 µL and flush the solution up and down to wash residual EtBr into the solution. Dispose of the pipette tip in the trash.

6. Pour the agarose solution into the gel tray and brush any air bubbles into a corner of the gel tray with a toothpick (found in Drawer A).

7. Insert the appropriate well comb (Drawer A) into the gel. Let it cool down and solidify.