The Basics of DNA Purification

DNA purification is a crucial element in a number of molecular tests, including PCR as well as qPCR and DNA sequencing. It eliminates contaminants such as salts, proteins, and other impurities which can disrupt downstream processes. It also ensures that the desired DNA is completely clean and present so that it can then be used for further analyses. The quality of DNA is measured using spectrophotometry (the ratio of A260 to A280) and gel electrophoresis and other methods.

In the initial stage of a DNA purification procedure the cellular structure will be disrupted with detergents or reagents such as SDS to release DNA. To further purify DNA, reagents that denature 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 acid solution by centrifugation and washing. If DNA is present in the sample, a ribonuclease treatment could be added to further denature the RNA. Finally, the nucleic acid is concentrated with ice-cold ethanol to isolate it from other contaminants.

Ethanol is an everyday solvent that can be used to remove salts and other contaminants from nucleic https://mpsciences.com/ acid samples. Researchers can evaluate the results of different experiments by using the standard ethanol concentration, which is a good choice for workflows with high-throughput. Other solvents such a chloroform and phenol may be utilized, however they are more harmful and require additional steps to prevent cross-contamination with other proteins or cellular debris. Modern techniques can speed up the process of purifying DNA by using low-ionic-strength ethanol, which has been proven to be just as effective as traditional organic solvents for purifying DNA [2626. This is particularly relevant when used in conjunction with a spin column-based extraction kit.