Strawberry DNA – Food Science
This lab shows how to extract and isolate the DNA from strawberries using household ingredients.
You've probably learned or heard about DNA, but have you ever seen it? With the Strawberry DNA experiment, you'll extract, isolate, and observe the DNA of a strawberry in a matter of minutes. It sounds impossible, but thanks to special characteristics of strawberries, it's actually very possible… and simple. You don't have to be a geneticist. You don't need a microscope. It's easy, fun, and all you need are some household materials.
- Isopropyl alcohol (5 mL)
- Dish soap (10 mL)
- Salt (1/4 tsp)
- Zipper-lock bag
- Water (90 mL)
- Measuring utensils
- Beakers or similar containers
- Pipette (optional)
- Put a bottle of isopropyl alcohol in a freezer. We'll come back to it later.
- Measure 90 mL of water into a beaker or similar container.
- Pour 10 mL of dish soap into the 90 mL of water.
- Add 1/4 tsp of salt to the liquid in the beaker.
- Mix it all up and now you've got a homemade extraction solution!
- Place one strawberry in a plastic zipper-lock bag.
- Pour your extraction solution into the bag with the strawberry.
- Remove as much air from the bag as possible and seal it.
- Use your hands to mash, smash, and mush the strawberry inside of the bag until there are no large pieces remaining.
- Pour the resulting strawberry and extraction solution mixture through a sieve and into a beaker or similar container.
- Use a spoon to press the strained bits of strawberry against the sieve, forcing even more of the solution into the beaker.
- From the container it is currently in, transfer the solution into a smaller beaker or similar container that holds around 50-100 mL of fluid.
- Add 5 mL of your chilled isopropyl alcohol to the solution and hold the mixture at eye level.
- Can you see how there is a separation of white “stuff” atop the rest of the solution? That's the DNA of the strawberry.
- Gently remove the DNA from the solution using tweezers.