The Basics of DNA Purification

DNA purification is a crucial component of many molecular assays, including PCR, qPCR, and DNA sequencing. It removes contaminants, such as salts, proteins https://mpsciences.com/2021/04/23/dna-purification-processes-for-different-applications/ and other impurities that could interfere with downstream processes. It also ensures the desired DNA is clean and available to be used in further studies. The quality of DNA can be evaluated by using spectrophotometry or gel electrophoresis and other methods.

In the beginning of a DNA purification process, the cellular structure will be disrupted using detergents or reagents like SDS in order to release DNA. To further remove DNA, reagents that denature proteins, such as sodium dodecyl-sulfate or Ethylene Diamine Tetraacetic Acid (EDTA) can be added to denature them. The proteins are removed from the nucleic acids solution by centrifugation and then washing. If RNA is present in the sample, a ribonuclease treatment could be added to further denature the RNA. Then, the nucleic acid is diluted with ice-cold ethanol to separate it from other contaminants.

Ethanol can be used as solvents to eliminate salts or other contaminants from nucleic acids. Utilizing a standard ethanol concentration allows researchers to examine the results of various tests, making it a suitable choice for high-throughput workflows. Other solvents, such as chloroform and phenol could be used, but these are more toxic and may require additional steps to avoid cross-contamination with other proteins or cellular debris. Newer methods can make it easier to complete the DNA purification process using low-ionic-strength ethanol, which has been proven to be as efficient as traditional organic solvents in purifying DNA [26]. This is particularly the case when paired with spin column extract kits.