DNA purification is among the most common and important methods in molecular biology. The purification of DNA aims at separation of the desired genetic material (chromosomal material) from contaminants such as proteins as well as RNA and cell membrane. This is a vital procedure in nearly all molecular applications. It must be carried out correctly in order to obtain top-quality, usable DNA.
There are a variety of different methods available for DNA purification, the selection of which is based on a variety of factors, such as the source materials and downstream applications as well as the cost and time constraints. The typical genomic and plasmid purification techniques include chemical treatment, enzyme digestion or mechanical disintegration of cells or tissues followed by salting out proteins and precipitating DNA using alcohol.
Ethanol precipitation is an inexpensive simple and quick method of desalting and concentration DNA. DNA molecules form aggregates in the presence of monovalent cations such sodium, and are then filtered https://mpsciences.com/ out of solution by large amounts of ethanol. This method allows the removal of organic compounds, and other impurities in a sample. It is frequently used in conjunction with other purification techniques.
Another method that is popular for DNA purification is anion exchange chromatography. The interaction between the negatively-charged DNA phosphate backbones and the positively-charged surface molecules of resins binds DNA in a solvent and positively charged resins. During the binding and washing processes the contaminating molecules are removed from the DNA using strict wash steps, and then the DNA purified is eluted using low salt conditions.