This document lists and briefly describes chemicals used in the DNA extraction process. Tris-EDTA buffer maintains the pH and protects DNA from degradation. Phenol and chloroform are used to remove proteins and lipids from the solution. Iso-amyl alcohol prevents chloroform reactions while iso-propanol and ethanol precipitate the DNA. RNAse breaks down RNA. CTAB solubilizes cell walls and membranes while NaCl neutralizes DNA charges. SDS removes oils and PVP binds phenolics. Beta-mercaptoethanol cleans tannins and polyphenols.

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Chemicals used in DNA Extraction
List of contents
 Tris-EDTA (TE BUFFER)
 Phenol
 Chloroform
 Iso-amy Alcohol
 Iso-propanol
 Ethanol
 RNAse
 CTAB
 NaCl
 SDS
 PVP (polyvinylpyrrolidone)
 Beta-mercaptoethanol

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Chemicals used in DNA Extraction
Tris-EDTA
Tris maintains the pH of the solution. Basically it interacts with the lipo-polysaccharides
present on the outer membraneof the cell, which helps to permeabilize the membrane.
This effect enhanced with the addition of EDTA (Ethylene Diamine Tetra Acetic acid), a
molecule chelating cations like Mg2+. The purpose of TE Buffer is to protect DNA or
RNA from degradation.
Phenol
Phenol is used to denature the proteins or it helps to remove non-polar proteins and lipids
from the solution.
Chloroform
Chloroform prevents cutting of DNA during isolation. It solubilizes lipids and a lot of
protein to remove them from the DNA.
Iso-amyl Alcohol
Iso-amyl Alcohol or isopentanol is used to prevent phosgene (CoCl2) from reaction of
chloroform (CH3Cl) with air.
Iso-propanol
Its main role is to precipitate the DNA, by engaging with the H2O molecules not giving
chance for the DNA to get dissolve in the H2O.
Ethanol
Ethanol is dehydrating agent. In DNA isolation, it is used for the precipitation of DNA
molecule. When a molecule is to be precipitated it should be dehydrated as the H2O
molecules forming a film around it prevent their interaction.
RNAse
An RNAse is an Enzyme that break down an RNA molecule. RNAses all added to the
final solution to ensure that no RNA is in the solution as it may interfere with the DNA in
the solution when trying to extract.
CTAB (Cetyl Trimethyl Ammonium Bromide)
CTAB is a best detergent to use during the Extraction/Isolation of highly Polymerized
DNA from Plant material. This detergent simultaneously solubilizes the Plant Cell wall

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and Lipid membranes of internal organelles and denatures proteins (Enzyme). Thus, the
DNA is not hydrolysed during the Isolation process and as long as vortexing or vigorous
shaking are avoided highly Polymerized (i.e. very high intact) genomic DNA is obtained.
NaCl (Salt)
The function of Salt is to precipitate DNA from the solution. The Salt neutralizes the
negative charge of the negatively Charged Phosphate in DNA.
SDS (Sodium Dodecyl Sulfate)
Is an Organic Compound, used as detergent that removes the oily strains in the DNA
extraction process. It is strong anionic detergent, it removes –ve ions from the protein and
destroys its confirmation because of loss of conformation the protein loses its structure.
PVP (polyvinylpyrrolidone)
It helps in removing phenolics by forming hydrogen bonds with them.
Beta-mercaptoethanol
It is added most of the times in the extraction buffers, it is a strong reducing agent to
clean tannins and other polyphenols present in the crude plant extract.