Strawberry DNA

At today’s March for Science, we spoke with the Weather Channel about the taste of science festival kicking off tonight in cities across the United States! Together, we conducted a fun experiment to show that science isn’t just something you do in the lab — the whole world around you is full of interesting things, if only you know where to look. 
— Washington DC, April 22, 2017

See for yourself — here's how to pull DNA from strawberries using everyday household items!

Materials

  • Two small and one medium-sized glass container
  • Strainer or cheese cloth
  • 2 strawberries
  • 3-5 tablespoon rubbing alcohol
  • 6 tablespoons of water
  • 1/2 teaspoon table salt
  • 2 teaspoon dishwashing soap

Put the bottle of rubbing alcohol in the freezer. It'll need to be chilled when we use it later.

Measure 6 tablespoons (90 ml) of water into a small glass container. Add 2 teaspoons (10 ml)  of the dishwashing soap to the water. Mix in the 1/2 teaspoon of salt, and stir until the salt is completely dissolved. This is our lysis buffer, which causes the cells in the strawberries to burst and release their contents — including DNA! — into the mixture. 

Place two strawberries into a plastic zipper-lock bag, and pour the lysis buffer into the bag. Remove as much air as possible from the bag and zip it shut. Being careful not to pop the bag, squish the strawberries with your hands until no large pieces remain. Mush the strawberry/lysis buffer mixture around with your hands for about one minute.

Pour the resulting strawberry/lysis buffer mixture through a strainer or cheesecloth into small glass jar. Use a spoon to press the mashed bits of strawberry against the strainer to force as much of the mixture into the container as possible.

Gently about 3-5 tablespoons of chilled rubbing alcohol to the mixture and hold the jar up to eye level. Do you see the cloudy separation of layers at the top? That's the strawberry DNA! Use a toothpick or tweezers to wind up the clump of strawberry DNA

Edward FlachComment