DNA purification is among the most commonly used and crucial methods in molecular biology. The aim of DNA purification is to distinguish the desired genetic, chromosomal material from contaminants (proteins, cell membranes and RNA). This is a vital process in nearly every molecular process and must be performed well to get top-quality, usable DNA.
There are a number of https://mpsciences.com/ different methods that can be used for DNA purification, the selection of which depends on several factors, including starting materials and downstream applications as well as the cost and time constraints. The common plasmid and genomic purification protocols include chemical treatment, enzyme digestion or mechanical disintegration of cells/tissues followed by salting of the proteins and precipitating the DNA using alcohol.
Ethanol precipitation is a simple, inexpensive and quick method for desalting and concentration of DNA. DNA molecules are aggregated in the presence monovalent cations, such as sodium and are then precipitated from solution using high concentrations ethanol. This technique permits the removal of salts, organic compounds and other impurities from the sample and is often employed in combination with other purification methods.
Another method of DNA purification is anion exchange chromatography. DNA in a solution is bound to positively charged resins by the interaction between the negatively charged DNA phosphate backbone and the positively charged surface molecules of the resin. During the binding steps it is possible to remove contaminants the use of a rigorous washing process. The DNA that is purified is eluted under low salt conditions.