DNA purification is a common and essential procedure in molecular biology. Purification of DNA aims at making it possible to separate the desired genetic material (chromosomal material) from contaminants such as proteins, RNA, and cell membrane. This is a crucial step in almost all molecular processes and must be performed correctly in order to obtain top-quality, usable DNA.

There are many different approaches for DNA purification. The selection is based on a range of factors such as the starting materials, downstream applications, cost, and time constraints. The common plasmid and genomic purification procedures include chemical treatment, enzyme digestion or mechanical disintegration of tissue/cells followed by salting of the proteins and precipitating the DNA with alcohol.

Ethanol precipitation is an easy, cost-effective and fast method of desalting and concentrating DNA. DNA molecules clump together in the presence monovalent cations, such as sodium and then they are removed from the solution using high concentrations ethanol. This method is used to eliminate organic compounds, and other impurities. It is usually employed in conjunction with other purification methods.

Another popular method for DNA purification is anion exchange chromatography. DNA in a solution gets bound to positively charged http://www.mpsciences.com/2021/04/15/gene-synthesis-and-transcription-processes/ resins through 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 making use of a strict washing process. The purified DNA then is eluted using low-salt conditions.