Why is phenol saturated with water or tris-HCl (pH 8) for DNA isolation ?
the pH of phenol determines if dna and rna will separate. the phenol degrades protein but acidic phenol retains rna while basic phenol allows both rna and dna to separate into the aqueous layer, Chloroform is often added to increase the density of the phenol layer to allow better separation of the 2 layers this link explains very well
http://physiology.med.cornell.edu/faculty/mason/lab/zumbo/files/PHENOL-CHLOROFORM.pdf
In DNA extraction Tris HCl has 2 function:
1-provide a appropriate Ph in solution in order to protect DNA during a extraction process and for its isolation(play bufferic role)
2-Destroy the membran's lipopolysacarids in order to helping DNA extraction from cells.
phenol is used to removing of proteins but it is better to use proteinase k for this purpose.
pH of the Phenol is important factor for isolation of RNA
- Badges
- Science topic
- Similar topics
- Analytical Chemistry
- Extraction