Purification of DNA

There are several methods for purifying DNA. The one you choose depends on the nature of your DNA sample and your downstream applications.

Alcohol precipitation

1. Nucleic acid precipitation
2. Ethanol precipitation of small DNA fragments
3. Isopropanol Precipitation for PCR Purification
   • use to concentrate DNA from PCR when you have verified that only a single PCR product exists. When performed properly this procedure exceeds the recovery of QIAquick PCR purification columns

Filtration / affinity columns

1. Centrifugal filtration/Nucleic acids
   • for small DNA fragments (~50-200 bp in length)
   • removes proteins, nucleotides and salts
2. Miniprep
   • for purifying plasmid DNA from E. coli cells
3. QIAquick PCR purification
   • for typical DNA fragments (> 200 bp in length)