DNA purification is one of the most popular and significant processes in molecular science. The purification of DNA aims at separating the desired genetic material (chromosomal material) from contaminants such as proteins or RNA as well as the cell membrane. This is a crucial process in nearly every molecular application and must be carried out correctly in order to obtain top-quality, usable DNA.
There are many different approaches for DNA purification. The choice is based on a variety of variables including the starting materials, downstream applications, cost, and time constraints. The common plasmid and genomic purification procedures include chemical treatment, enzyme digestion or mechanical destruction of cells or tissues followed by salting out of proteins and then precipitating the DNA using alcohol.
Ethanol precipitation is an inexpensive, quick and simple method of desalting and concentrating DNA. DNA molecules form aggregates in the presence of monovalent cations such as sodium, and are then filtered from the solution by using large amounts of alcohol. This method is used to eliminate organic compounds, and other impurities. It is commonly utilized in conjunction with other purification methods.
Another method used for DNA purification is anion exchange chromatography. DNA in a solution is bonded to positively charged resins via the interaction between the negatively charged DNA phosphate backbone as well as the positively charged surface molecules of the resin. During the binding process it is possible to remove contaminants using a stringent washing process. The DNA that is purified is eluted using low-salt conditions.