DNA purification is one of the steps in the sample preparation process. It removes enzymes and salts from the lysed samples or PCR products, prior the cloning and sequencing process. It also removes unwanted PCR artifacts such as primer dimers or unincorporated nucleotides. DNA purification in molecular biological research is an essential step that requires careful planning to ensure high-quality, reliable results.
Purifying DNA can be done by a variety of methods. Traditional DNA isolation techniques involve various steps like leukocyte isolation or red blood cell lysis in order to remove heme proteins, which block the PCR reaction, deproteinization and the treatment of RNAse. These include ethanol and isopropanol precipitation and finally DNA elution. Most of these protocols require the use of specially designed equipment, like an electrophoresis machine and biosafety cabinets due to the hazardous intercalating dyes that are used in the electrophoresis gel.
Other DNA purification techniques use spin columns or 96-well filter plates to eliminate contaminants by adsorbing them to the surface of the column or plate. These methods can be lengthy particularly when you have many samples or if the columns need to be manually refilled.
Dipsticks reduce the number of sample processing steps from six to three. They bind nucleic acids using a waxy cellulose-based material and then release them when water is present. This method is particularly effective in low-resource areas, like remote field sites or teaching laboratories. Its simplicity (30 s per sample) makes it suitable for diagnostic molecular tests such as those for disease detection and genotype screening.