Thursday, 15 March 2012

Science: How to extract your own DNA!

This experiment will show you how to extract your own DNA. Warning WILL cause great excitement!



What you'll need:

  • Water (500ml)
  • Dish Soap (washing up liquid)
  • Salt
  • Food Colouring (optional)
  • Isopropyl Alcohol (70%) I have seen that vodka can be used too.
  • Measuring beaker
  • Measuring jug
  • Clear cups like glass or disposable plastic cups.
  • test tubes
How to do it:

STEP ONE

Mix 500ml of water with 1 tablespoon of salt.


STEP TWO

Stir until salt is dissolved.






STEP THREE

Transfer 10ml of your salt water into a clear cup.




STEP FOUR


Spit (as much as possible) into the ten ml of salty water you put into a clear cup and then pour it into a test tube or leave it in the clear cup if you have none.

TIP: Use your tongue to gently scrap some cheek cells off. 




Your cheek cells are now suspended in salt water!

STEP FIVE

Gently stir the salt water with one drop of washing up liquid.  (Try not to make bubbles)

It's the soaps job to breakdown the membranes, releasing the DNA

STEP SIX

You may want a face mask and some goggles for this step if you are using the isopropyl alcohol!  In a separate cup mix 50ml of Isopropyl alcohol and 2-3 drops of food colouring (Red, Blue or Green is best)  You can use the vodka instead but I use the isopropyl.



STEP 8

Tilt the test tube or the cup, containing your small amount of salt water, washing up liquid and spit, and gently pour the Isopropyl mixture down the side of the test tube/cup so that it forms a layer about 2cm thick on top!  It is important that this bit is done carefully.



You should have something that looks like this!

STEP NINE

Wait about 2 to 3 minutes.  If you've done it right you'll see clumps and strands in the alcohol layer, the top layer! 



You can try gently pulling out one of the strands like this if you like.  If you do this you can then put it on a slide and look at it under a microscope to see it up close too!

IF YOU'VE DONE THIS YOURSELF AT HOME THAT'S YOUR DNA HOW VERY COOL!

12 comments:

  1. Brilliant! x So inspirational to have this picture of homeschool life. x

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  2. Wow, that's fantastic! My boys are really excited to try this - thanks!

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  3. Brilliant! We will have to try that :)

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  4. wow,,,cant wait to try thos with my tribe! thankyou x

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  5. Great post, we extracted onion DNA, but extracting own DNA will be a lot more exciting.
    x

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    1. It does add to the excitement! :D

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  6. Replies
    1. Thank you Ayesha! What lovely feedback! I hope you enjoy some of the other experiments too x

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