Team:Grenoble/Biology/Protocols/Gel

From 2012.igem.org

Revision as of 09:10, 28 August 2012 by Adeline millet (Talk | contribs)

iGEM Grenoble 2012

Project

Gel electrophoresis and EtBr revelation

Goal

Separate DNA strands of different lengths.

Prepare the gel

  1. Add 1 g of agarose powder to 50 mL of 1X TAE buffer.

  2. Heat the solution using the microwave until the powder is completely dissolved.

  3. SAFETY AND USEFUL RECOMMANDATION
    When heating the mixture it is important to use an adaptable container. Putting metallic things in the microwave is dangerous. It causes the formation of intense electric current. Actually falcon tubes are used. But there must be left open, because the elevation of temperature can make the pressure increase. And if the tubes are not open, these one could explose, causing the deterioration of the microwave and of the preparation. It also can burn people. What is done to prevent this situation is that the microwave is turned off every 2 minutes to see if the preparation is good or not.

  4. Once the solution is cool enough to be touched, pour it into gel cast (don't forget the comb).

Load the gel

  1. When the gel is solid, remove carefully the comb.

  2. Place the gel in the buffer tank and cover it with the 1X TAE buffer solution.

  3. Load each sample into the wells (don't forget the loading dye and the DNA ladder).

Run the gel

  1. Connect the generator.

  2. Chose the right voltage.

  3. Put the device on.

  4. SAFETY AND USEFUL RECOMMANDATION
    The generator can deliver over 130V. The risk of electrocution for people is generally around 50V. That is why some recommendations must be followed. First before using the electrophoresis device, users should check if they have all parts of the device, because it is a removable one. They also have to check that each part corresponds to the good device. Indeed there are different kinds of tank and using parts of different devices will not make the device function safely. That is why we managed to number each part in order to know from which device they belong to. Then the generator must not be in presence of water and its vents must not be blocked, because the device will become hot during its use. Moreover the generator has two main safety protections. The first one is a detection of migration buffer. This detection does not let the device generate electricity until the migration buffer has been put in the tank and has reached a correct level. This is a protection both for the device and for users. Thanks to this protection the device could not generate electricity when something was not be done correctly by users. Moreover it also prevents users to be surprised by the production of electricity during the manipulation. The second protection is a mechanic one. Thus it seems to be more efficient. This protection prevents the generator to produce electricity when no lid is put on the tank. With this, there is less risk of injuries and accidents. But it should be use correctly after all.