DNA Extraction Results
Country: United States
Date: July 2005
I have some questions regarding the DNA extraction
experiment from onion cells.
1)what is the purpose of the usage of salt to make the DNA extraction mix?
2)at the end of the experiment,the DNA of the onion cells will appear as a
'fluffy' white solid that floats on top of the mixture of clear liquid and
ice cold 95 percent ethanol.why does the DNA floats?
The purpose of the salt is to precipitate protein. I can't explain why the
DNA is floating. In most DNA extraction methods, DNA ends up as a pellet at
the bottom of the alcohol phase because it is insoluble in ethanol and has a
density of approx. 1.8 g/cc.
Ron Baker, Ph.D.
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Update: June 2012