How to Extract DNA from a Strawberry: A Fun Kitchen Science Experiment

Learn how to extract real DNA from strawberries using simple household ingredients in this engaging science experiment for kids.

  1. What You'll Need. Gather these common household items: 1 fresh strawberry, 1/2 cup warm water, 1 tablespoon liquid dish soap, 1 teaspoon table salt, 1/4 cup rubbing alcohol (kept in the freezer for at least 30 minutes), a small bowl, a fork or potato masher, a coffee filter or fine mesh strainer, a clear glass or test tube, and a wooden stick or cotton swab for collection.
  2. Prepare Your Strawberry. Remove the green leaves from your strawberry and place it in the small bowl. Mash the strawberry completely with your fork or potato masher until it becomes a pulpy mixture. The more thoroughly you mash it, the more DNA you'll be able to extract. Make sure there are no large chunks remaining.
  3. Create the DNA Extraction Solution. In a separate container, mix the warm water, dish soap, and salt together. Stir gently until the salt dissolves completely. This solution will help break down the cell walls of the strawberry to release the DNA inside.
  4. Mix and Wait. Pour the soapy salt solution over your mashed strawberry and stir the mixture gently for about 30 seconds. Let this combination sit for 2-3 minutes without stirring. During this time, the soap is breaking down the cell membranes while the salt helps the DNA clump together.
  5. Filter the Mixture. Place your coffee filter or fine mesh strainer over a clean glass and carefully pour the strawberry mixture through it. Allow the liquid to drip through completely, leaving the solid pieces behind. You should have about 1/4 cup of cloudy liquid in your glass.
  6. Add the Cold Alcohol. Very slowly and carefully, pour the cold rubbing alcohol down the side of your glass so it forms a layer on top of the strawberry liquid. Do not mix or stir. The alcohol should float on top, creating two distinct layers.
  7. Watch the DNA Appear. Within a few minutes, you'll see white, stringy material forming at the boundary between the two liquids. This is the actual DNA from your strawberry! The DNA will continue to accumulate and may float up into the alcohol layer. Use your wooden stick or cotton swab to gently collect these white strands.