Genomic DNA and total RNA extracted from cells are mixed with proteins, polysaccharides, and nucleic acids of various sizes. The process of removing these "impurities" is the process of nucleic acid purification. During the isolation and purification of nucleic acids, in order to prevent the denaturation and degradation of nucleic acid macromolecules, it must be operated at a low temperature of 0 ~ 4℃. The nuclease hydrolysis is a serious obstacle in the past to prepare active nucleic acid macromolecules. Therefore, inhibition of nuclease activity is the main measure to ensure the integrity of nucleic acid macromolecules in the purification process.
DNA extraction is a method of obtaining DNA from samples such as cells. DNA extraction is divided into three basic steps:
Fig. 1 Basic steps of all DNA extraction methods.
Different extraction methods have different DNA yields and purity. Common DNA extraction methods are: organic extraction, magnetic purification, ion exchange technology, salting out method, cesium chloride density gradient centrifugation method and Chelex 100 resin purification method. Different cell DNA, its extraction method often needs to be improved and optimized. Cetyltrimethylammonium bromide (CTAB) and isothiocyanate (GITC) are commonly used to extract plant tissue DNA.
RNA extraction is the purification of RNA from biological samples. The problem with this step is that the cells and tissues are full of ribonucleases, which quickly degrade RNA. There are several methods for molecular isolation of RNA from samples. One of the most commonly used methods is guanidine thiocyanate-phenol-chloroform extraction. In addition, using a mortar and pestle or a professional electric grinder to extract RNA from liquid nitrogen is also an effective method to prevent ribonuclease.
Creative Biogene can extract genomic DNA and total RNA from a variety of materials. Due to the different amounts of genomic DNA and total RNA extracted from different types of materials, even if the same material has different freshness, the difference is relatively large, so please provide fresh and sufficient experimental materials, and use specific methods to store and transport them. The services we can provide are as follows.