DNA Necklace Lab

Materials• clear sports drink or 0.9% salt water• Dixie cup• Sharpie marker• 15 mL disposable test tube• test tube rack• microcentrifuge tube• transfer pipette• yarn (2 feet)• ice cold isopropyl, 70% ethanol,

or rubbing alcohol• diluted clear dish soap solution (50/50)

PrepareWrite your name on:

• test tube• cup

PrepareMeasure 2 mL of sports drink using your pipette and test tube. Pour it into the small cup.

Slough off Cheek Cells

Swish the sports drink VIGOROUSLY for 60 seconds. You are trying to slough off as many cheek cells as possible.

Slough off Cheek Cells

Spit the sports drink back into the small cup.

Release the DNA from CellsCarefully pour 2 mL of clear soap solution into the test tube.

Release the DNA from Cells

Carefully pour the saliva/sports drink mix into the test tube.

Release the DNA from Cells

GENTLY mix the test tube by holding your thumb over the opening and inverting the test tube 5 times. DO NOT create bubbles.

5 times!

Release the DNA from Cells

The soap solution breaks the cell membranes and releases the DNA. Cell membranes are made of lipids (This is like soap breaking down grease on dishes.)

Separate out the DNA

Tilt the test tube.

GENTLY pour alcohol down the side of the test tube using your pipette until the total volume reads 13 mL.

You are trying to form 2 separate layers. DO NOT MIX!!!

Separate out the DNA

Let the test tube stand in the

rack for 10 minutes.

You will see white or clear

strands appearing – this is YOUR

DNA precipitating (solidifying)!

While waiting, get string and beads for your necklace.

(no more than 6 beads please)

Extract the DNAUse the pipette to GENTLY remove the strands of DNA and squirt it into your microcentrifuge tube.

Add a small amount of leftover liquid into the microcentrifuge tube to preserve your DNA.

Create Your Necklace

Center your string on the cap’s hinge, and then snap it shut.

Add some beads and tie your necklace around your neck.

Show off to all your friends!