Extract DNA
Extract DNA from strawberries using dish soap, salt, water, and cold alcohol; observe and collect visible white, stringy DNA with adult help.
Step-by-step guide to extract DNA from strawberries
What Is DNA for Kids | An easy overview of DNA for children | Awesome DNA Facts
Step 1
Ask an adult to put the rubbing alcohol in the freezer for at least 30 minutes so it becomes very cold.
Step 2
Wash your hands and clear a small clean area to work on.
Step 3
Remove the green tops from 2 or 3 strawberries and place the berries into the resealable plastic bag.
Step 4
Press all the air out and mash the strawberries inside the bag for about 60 to 90 seconds until they are very pulpy.
Step 5
Measure 1/2 cup of water into the small bowl.
Step 6
Add 1 teaspoon of dish soap to the water in the bowl.
Step 7
Add 1/4 teaspoon of salt to the bowl and stir the liquid gently for about 30 seconds to make the extraction solution.
Step 8
Pour about 2 to 3 tablespoons of the soap and salt solution into the bag with the mashed strawberries, seal the bag, and gently mix for 60 seconds.
Step 9
Place the coffee filter or a folded paper towel over the clear glass and slowly pour the strawberry mixture through it so the liquid drips into the glass.
Step 10
With an adult helping, slowly pour the very cold rubbing alcohol down the side of the glass until a 1-inch layer of alcohol sits on top of the strawberry liquid.
Step 11
Watch the glass without stirring and wait for 1 to 5 minutes for white stringy bits to form where the two layers meet.
Step 12
Gently insert the wooden stick or toothpick into the alcohol layer and twirl slowly to spool out the white stringy DNA.
Step 13
Take a picture or make a short note about your DNA and share your finished extraction on DIY.org
Final steps
You're almost there! Complete all the steps, bring your creation to life, post it, and conquer the challenge!
Help!?
What can I use if I can't find rubbing alcohol or a coffee filter?
If you can't find rubbing alcohol, you can use very cold clear vodka chilled in the freezer like in step 1 (though the DNA may be fainter), and a clean folded paper towel, fine mesh, or cotton cloth can replace the coffee filter in step 7.
I mashed the strawberries and followed the steps but don't see any white stringy bits—what went wrong?
If no white bits form, make sure the strawberries were mashed until very pulpy in step 4, that you used the correct soap and salt amounts when making the extraction solution in steps 5–6, and that you slowly pour the very cold alcohol down the glass side in step 9 so it forms a separate layer instead of mixing.
How can I adapt this extraction for younger or older kids?
For younger children, have an adult handle the freezer alcohol and the pouring step (steps 1 and 9) while the child mashes strawberries in the bag (step 4) and watches the DNA, and for older kids, have them precisely measure the soap and salt (steps 5–6), test variables, and record results.
How can we extend or personalize the DNA extraction activity?
To extend the activity, compare yields by extracting DNA from different fruits (replace strawberries in step 3), vary the amount of dish soap or salt in steps 5–6 to see the effect, and label, photograph, and decorate jars or notes to personalize and present your findings.
Watch videos on how to extract DNA from strawberries
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Introduction to DNA structure
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Facts about DNA and genetics
🧬 Strawberries are octoploid — garden strawberries have eight copies of each chromosome, so they contain lots of DNA!
🧪 You can extract visible DNA at home using dish soap, salt, water, and very cold alcohol (always with adult supervision).
🧼 Dish soap helps break open cell and nuclear membranes, while salt makes the DNA clump together so it can be seen.
❄️ Very cold alcohol (ethanol or isopropyl) causes DNA to precipitate out as white, stringy strands you can spool onto a stick.
👀 In cells DNA is microscopic, but extraction pools billions of molecules so you can actually see them as slimy threads.
