DIY Science: Biohacking Fruit DNA

Burst open fruit cells to extract visible DNA.

Extract real fruit DNA from strawberries

https://youtu.be/FtjihTA-_CQ

Here's what you need to give this a try at home:

• 4-6 Strawberries

• 1 teaspoon of Salt

• 2 teaspoons of Washing-up liquid soap

• 2 teaspoons of Rubbing alcohol

• Water

• Ice

• Cocktail sticks

• Sieve

• Cup

• Sandwich bag

• Teaspoon

Recipe:

1. Prepare by chilling the rubbing alcohol in the freezer and removing any leaves or stems from the strawberries.

2. Add the strawberries to a Ziplock bag and crush the fruit with your fingers for about 1 minute.

3. Add the washing up soap and salt to a cup of water and mix with the spoon.

4. Add the washing up soap mixture to the fruit in the bag. Close the bag and gently squash the fruit again for 2 minutes to mix the solution until there are no big pieces left.Tip: remove as much air as possible before you close the bag so that it doesn’t burst!

5. Leave it to stand for about 5 minutes.

6. Place the sieve over the cup. Pour the fruit mixture through the sieve to remove the pulp and seeds until you have a clear solution - about 10 ml, or 2 teaspoons, is enough.

7. Remove the sieve and slowly pour the cold rubbing alcohol down the inside of the beaker with the filtered liquid. Don’t mix or stir.Tip: The rubbing alcohol should sit on top of the filtered liquid. Within a few seconds some cloudy, white clumps will form in this top layer - that’s fruit DNA.

8. Pick up the DNA with the toothpick to examine it more closely!

The science:

DNA is normally a long, stringy molecule that stays dissolved in water but the salt helps it stick together so that what you see are clumps of tangled DNA molecules!

When salty DNA comes in contact with alcohol it becomes undissolved. This is called precipitation. The physical force of the DNA clumping together as it precipitates pulls more strands along with it as it rises into the alcohol.

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