Purification Of The Dna Essay

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Procedures
Purification of the DNA
1. Using the kitchen knife, cut up the cow's liver into three small pieces measuring approximately one-inch (3 cm) cubed.
2. Place the pieces of liver into the blender.
3. Add the salt and warm water to the liver in the blender. Make sure the water covers the liver pieces.
4. Blend on high with the cover on for 10 to 15 seconds.
5. Strain the blended mixture through cheesecloth or a coffee filter into a beaker or large drinking glass.
6. Add the dishwashing liquid, stir, and let sit for 10 minutes.
7. Fill a test tube or small narrow glass one third full with the liver mixture.
8. Add a pinch of either the meat tenderizer. Wait 20 minutes.
9. Tilt the test tube or glass, and slowly add an equal amount of the cold alcohol by pouring the alcohol down the sides of the test tube. Wait 20 minutes.
10. Stringy DNA should appear as a layer between the bottom mixture and the alcohol on the top.
11. Insert a stirring rod into the stringy DNA. Spool the DNA around the rod like you are gently swirling up cotton candy. Filter your sample’s juice through a coffee filter into a small beaker. You can also use 3-4 layers of cheesecloth instead of coffee filters. Coffee filters, however, are better …show more content…

Gradually add ice cold 99% propanol by drizzling it down the side of the beaker. The isopropanol will form a clear layer on top of your sample. Add 2 volumes (this means approximately two times the volume of the sample present) of ice cold 99% isopropanol down the side of the beaker with a straw or pasteur pipette. It is helpful to tilt the beaker as you do this to increase the surface area of the juice layer in contact with the alcohol. Also, do this step slowly to enable the alcohol to form a layer on top of the juice layer. If the alcohol does not form a separate layer, the alcohol will be too dilute to precipitate the DNA. As you let the beaker sit, the DNA should precipitate. The longer you wait, the more DNA you should

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