In this post, I will be explaining an experiment that involves extracting DNA from strawberries! Let’s get started.
You will need: 2 strawberries, a ziploc bag, 2 teaspoons of dish soap, ½ cup of water, 1 teaspoon of salt, a coffee filter or strainer, hand sanitizer and a toothpick.
Before we get started, put the hand sanitizer in the fridge! I used gel hand sanitizer, but if you have a spray one, that might work better.
First, cut the green leaves off the strawberry and place the berries in a ziploc bag. Use your hands to mash up the strawberries until they are crushed.
To make the DNA Extraction liquid, you need to mix the dish soap, salt, and water in a glass. Add 2 teaspoons of this liquid to the strawberries bag and smush it around some more. Be careful to not foam the mixture, just gently press it to ensure it is all mixed up!
Now, grab your filter (whether it be a coffee filter or strainer, I think the coffee filter is easier to use, but use whichever you have at home) and strain the strawberry liquid! You want to make sure you have as much of the liquid as possible with no solid chunks in it! I used a strainer and pushed down on the strawberry mixture with a spoon until all the liquid was removed.
With the strawberry liquid, add in an equal amount of the cold hand sanitizer. Make sure you do not mix it! Within a few seconds, you’ll begin to see a white cloudy substance form at the top. This is the DNA! Take your toothpick and pick up the DNA.
Just like that, we extracted the DNA from the strawberry! But… how did this happen?
Well. all living cells have DNA in them. Remember the DNA Extraction liquid we made (dish soap, salt, and water)? The dish soap dissolved the cell membranes in the strawberry. The salt broke up the protein chains in the strawberry and made them insoluble in the water. This caused the DNA strands to be released! The DNA is not soluble in hand sanitizer, so it precipitates from the mixture and goes to the top! So, we are able to pick it up!
Pretty cool, right!?
Through this experiment, your kids can physically see DNA! Check us out on TikTok and Instagram for more content, and check out our other blog posts posted on stemchef.com for more fun food based experiments!
- Roshnee Gulati