PCR Detection of Genetically Modified Foods: Electrophoresis (Part III:…
PCR Detection of Genetically Modified Foods: Electrophoresis
Part V: Photographing the Gel
Use results to complete lab assignment.
Turn off power and unplug the gel box. Then remove the top of the gel box.
Label edge of plastic weigh boat with your name.
Remove gel and put it in weigh boat. Push exposed edge of gel with finger to make it slide off tray and into weigh boat.
Pour buffer back into stock container marked TBE.
Put date and initials on photograph.
Only dispose of gel in biohazard box once you are sure that both photographs have come out okay.
Use numbers or symbols for each lane and make a legend to explain what each number represents.
Align photo so that wells are at top. Use permanent marker to label lanes of gel.
Part IV: Running Gel
Record voltage you used and the amount of time you let it run.
Put lid back on box.
Let it run for 40-60 minutes, or until faster loading dye band has traveled 2/3 of the length of the gel.
Look out for if the machine is already on or if somebody is already using it to run a sample.
Look for bubbles forming near electrodes at base of gel box and make sure current running through circuit is greater than 0.
Set to 115-120 volts.
Part III: Load DNA Samples into Gel
Tell them if you screw up and lose sample.
Load 15 uL of each remaining sample into appropriate wells of your gel.
Don't hit second stop on micropipettor when loading well.
Once 20 minutes have elapsed since the gel was poured, continue.
Move any air bubbles in well out with a pipette tip.
Remove barriers and wipe them with a wet tissue and dry tissue.
Load 10 uL of DNA ladder to each well of gel.
Pour TBE buffer into gel box until it just covers surface of gel. Don't want any gel sticking up above top of buffer.
Move gel box near power supply you plan to use.
Remove comb and wipe it with a moistened lab tissue and put it back in front of lab.
Part II: Prepare Samples
Obtain DNA ladder sample that contains loading dye.
Write down which sample goes in each well. DNA ladder belongs in first well.
Vortex loading dye.
Vortex each sample.
Add 5 uL of loading dye to each PCR sample.
Part 1: Pour Agarose Gel
Wear gloves for protection.
Wait 20 minutes for gel to set.
Lift top of gel box and place tray. It is clear and looks like a U.
Fill tray with molten agarose until 2/3 full.
Place the black barriers to keep the agarose inside the tray.
Put comb far from red so you get a good run.
Choose 8-well comb, can also use 16.