PCI extraction

PCI (phenol-chloroform-isoamylalchol) extraction is applied to remove protein portion in the solution to extract nucleicacids.


  1. Add PCI solution to DNA solution.
  2. Close lid tightly and vortex briefly.
  3. Centrifuge for 5-15min at 10,000 rpm.
  4. Carefully transfer aqueous layer (DNA solution) into a new tube.
    Precipitates are denatured proteins.
  5. Repeat #1 to #4 while the precipitates appears.
  6. Finally, add chloroform and vortex briefly, and centrifuge.
    This process is to transfer phenol in the aqueous layer to the chloroform layer.
  7. Collect aqueous layer and extract DNA by Ethanol precipitation.


for DNA extraction

  • Tris saturated phenol + CIA(1:1)

for RNA extraction

  • H2O saturated phenol + CIA(1:1)


  • Chloroform + isoamylalchol (24:1)

Water-saturated phenol

  • Liquid phenol + H2O (4:1)