It is essential to have high quality DNA that is free of contaminants such as protein, debris, and RNA before performing a PCR, cloning, or DNA sequencing. Purifying DNA is also referred as DNA Isolation and is a vital step in molecular biology. This article will teach you the basics of DNA extraction and how to optimize it to achieve better results.

The first step in the DNA purification process is to prepare a solution that comprises a mixture of water and an alkaline buffer. This buffer makes DNA soluble, which means it can be easily separated from other components of the sample. Once the DNA has been placed in an alkaline and water solution, it is then treated by chaotropic salts or detergents to break down cell membranes and nuclei and release DNA (cell lysis). RNase may also be added to remove any contamination RNA from the sample.

The DNA is separated by organic solvents such as phenol or chloroform from other components of the cell such as proteins and fats. Once the DNA has been removed from proteins and lipids, it is able to be precipitated using ethanol or isopropyl alcohol (rubbing alcohol).

The purity of the DNA may be verified http://www.mpsciences.com/2021/04/23/dna-purification-processes-for-different-applications/ using spectrophotometry or gel electrophoresis. A good quality DNA sample should have an absorbance ratio of between 220 nm to 280 nm. 1.8. A low ratio may indicate an issue with the protein binding steps, or salt carryovers from the wash or bind buffers.