DNA ELECTROPHORESIS

STUDENT HANDOUT

Page 1


Day 2 "Practice Techniques" Carefully follow these procedures

Part A Practice preparation for a digest:

  1. Each team is to obtain a set of four tubes containing colored liquids and four empty reaction tubes labeled "A", "B", "C" and "D".
    TUBE
    Solution 1

    (Yellow)

    Solution 2

    (Red)

    Solution 3

    (Blue)

    Solution 4

    (Green)

    A
    4 µl
    5 µl
    1 µl
    -
    B
    4 µl
    5 µl
    -
    1 µl
    C
    4 µl
    5 µl
    1 µl
    -
    D
    4 µl
    5 µl
    -
    1 µl
  2. Using the proper techniques for the 0.5-µl pipettor, add the required amounts of the different solutions (one at a time) to each reaction tube as shown in the matrix above. (Take turns adjusting the pipettor between solutions)
  3. After you have added all the solutions, show your teacher that you have completed this step correctly. You should have three separate droplets on the walls inside of your tubes.
  4. Add 2 µl of practice loading dye to each of your tubes
  5. Mix your solutions by centrifuging for a few seconds.
  6. A total of 12 µL was added to each of your tubes. To check that your measurements were accurate, set the gel loading pipettor (Green plunger: 10-50 µL size) to 12 µL and try to withdraw the total contents of your tube into the pipettor tip. (There should be no fluid left behind in the tube.)
  7. Return the contents in the pipettor tip to your reaction tube and centrifuge a few seconds to pool the solutions at the bottom of the tube. (Step #6 and 7 are important; you will need to practice them several times.)
  8. Wait for your turn to practice loading a gel.