Introduction: How to Extract DNA From Strawberry
Here's how to extract DNA from a strawberry. You don't need to be a professional scientist to do this, and you probably have most of the materials at home!
You will need:
- 2 plastic cups (should hold at least a 16oz)
- 1/2 cup icy cold water
- Soap (dish soap, hand soap, or detergent)
- 1 large, cold strawberries
- Cold 70% isopropyl alcohol
- Plastic, sealable bag
- Mixing stick
- Coffee filter
Step 1: Make the Extraction Solution
1: Put 1/2 cup ice cold water in cup
2: Add 1/2 teaspoon of salt
3: Add 2 teaspoons liquid soap
4: GENTLY mix, careful not to create bubble but dissolve the salt
The salt will break apart the proteins and other things that come out of the strawberry cells. The soap will melt the cell walls because the walls are made of lipids (or fats). Just like doing dishes, soap melts away the grease and fat.
Set solution aside
Step 2: Strawberry Smash!
Remove the leaves and core of the strawberry. Put the strawberry into a sealable plastic bag. Firmly smash the strawberry with your fingers. Do this for 2 minutes so there is no big chunks left.
Pour in the extraction solution, remove as much air as possible, seal bag and gently squish the bag for 2 minutes. Let the bag sit for 8 minutes to let the soap and salt extract the DNA from the cells.
Step 3: Filtering
Rubber band a coffee filter onto the cup and pour in the mixture from the bag. Take off the rubber band, grab the filter into a sack, and GENTLY GENTLY GENTLY squeeze. If you squish too hard the filter will break and the strawberry mush will go into the cup.
Swirl the cup a few times again being carefully not to create bubbles. Pour the icy cold isopropyl alcohol into a cup. Tilt the strawberry liquid cup to the side and SLOWLY pour the isopropyl into in cup. Pour about 3/4 inch of isopropyl.
Step 4: Look at the DNA
Since the isopropyl is lighter than water, it will float on top of water. Let the moisture sit for 20 minutes and you will see stringy white stuff on the surface. That stuff is the DNA!!!
Take a toothpick or your mixing stick and you can pull the DNA up. It will look like sticky snot. Those thin strands of white are hundreds of strands of long DNA.
If you want, gently spool up the DNA and put it into a test tube or shot glass with some isopropyl in it. You can show you're friends if you want! :D