It is essential to have high-quality DNA that is free of contaminants like proteins, debris and RNA prior a PCR, cloning, or DNA sequencing. Purifying DNA is also known as DNA Isolation, and is an essential step in molecular biology. In this article, you will learn the fundamentals of DNA purification and how you can optimize your DNA extraction strategies for better results.
The initial step in the DNA purification process is to prepare a solution which includes a mix of water and an alkaline buffer. This buffer makes the DNA soluble so that it can be easily separated from the other components of the sample. After the DNA is placed in an alkaline and water solution, it’s cleaned with detergents as well as salts that break down cell membranes as well as nuclei. This lets the DNA out. RNase can be added to the sample to remove any DNA contamination.
The DNA is then separated by organic solvents such as phenol or chloroform from other cellular components such as proteins and fats. After the DNA is separated from proteins and lipids, they can be precipitated using ethanol or isopropyl alcohol (rubbing alcohol).
Spectrophotometry and electrophoresis may be used to determine the quality of DNA. A good quality sample of DNA should have an absorbance ratio between 250 nm and 280nm.
http://www.mpsciences.com/2021/04/23/dna-purification-processes-for-different-applications/
