DNA purification is a vital step in many molecular assays that include PCR as well as qPCR and DNA sequencing. It removes contaminants such as proteins, salts and other impurities that could interfere with downstream processes. It also ensures that the desired DNA is in good condition and pure to be further analysed. The quality of DNA can be evaluated through spectrophotometry and gel electrophoresis and various other methods.
In the beginning of a DNA purification procedure the cellular structure is going to be disrupted by using detergents or reagents like SDS in order to release DNA. To further purify DNA, reagents that alter proteins, such as sodium dodecyl sulfate and Ethylene Diamine Tetraacetic Acid (EDTA) can be added to denature them. The proteins are then removed from the nucleic acids solution by centrifugation and washing. If RNA is found in the sample, it can be further denatured by adding ribonuclease. The nucleic acid is concentrated with ice-cold ethanol to remove it from other contaminants.
Ethanol is solvent to eliminate salts and other contaminants from nucleic acids. The use of a standardized concentration of ethanol allows researchers to compare the results of different studies, making it a good option https://mpsciences.com/2021/04/23/dna-purification-processes-for-different-applications/ for workflows that require high-throughput. Other solvents such as chloroform and phenol could be utilized, but they are more toxic and may require additional steps to avoid cross-contamination with other proteins or cellular debris. The purification of DNA can be made simpler by using ethanol that has a low ionic strength. This has been shown to be as effective as conventional organic solvents for making DNA purer. This is especially applicable when paired with a spin column extraction kit.
