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Name: Emmanuel
Status: student
Grade: n/a
Location: Outside U.S.
Country: Ghana
Date: Spring 2013

Why rna is isolated with lower ph and salt concentration as compared to that of dna?

Hi Emmanuel,

Thanks for the question. RNA does not form a double helix like DNA does. RNA is typically a single strand. Double helix DNA is not as soluble as RNA and therefore precipitates before RNA does. In order to make RNA precipitate, the pH has to be lower and the ionic strength (a fancy name for the salt concentration) has to be greater.

I hope this helps. Please let me know if you have more questions. Thanks Jeff

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