Onion DNA Preparation

Materials:

Hot water bath

Diced onion

Homogenizing Solution

Beakers

Blender

Cold Bath

Cheesecloth

Procedure:

1.) Weight out 50g of diced onions and transfer it to a bigger beaker.

2.) Add 100ml of homogenizing medium and incubate in bath water for 15 minutes.

3.) Cool the mixture in an ice bath to 20 degrees celsius.

4.) Homogenize in the blender for 3-5 second intervals at low speeds.

5.) Pour into 1000 ml beaker and place in ice bath for 15-20 min.

6.) Filter the mixture through 4 layers of cheesecloth into a 250 ml beaker. Leave the foam behind.

7.) Dispose of your onion remains in the trash.

8.) Add 2 ml of Chloroform to the homogenate with a 5 ml pipette.

9.) Swirl the flask gently.

10.) Pour the homogenate into another 125 Erlenmeyer flask and leave the chloroform and protein layers on the  bottom. Rinse the flask carefully and use again.

11.) After the deproteinization, pour the solution in a 125 Erlenmeyer flask. Decant, making sure there are no proteins or chloroform in the homogenate even at the risk of leaving some homogenate behind.

12.) Pour the waste chloroform into a labeled waste bottle on the side bench. Do not pour down the drain.

13.) Place the beaker with the homogenate in an ice bath and cool until it reaches 10 to 15 degrees celsius.

14.) Slowly add ice-cold ETOH down the side of the beaker.

15.) Spool out and wind the stringy DNA on a glass rod by rotating the rod in one direction in the beaker.

16.) Interpret the results.