What are the requirements for nucleic acid purification?

For many molecular biology and genomics applications, from cloning and PCR to genome sequencing and chip analysis, DNA purification is the only method. However, it is not easy to choose the best purification kit. For example, when you purify genomic DNA, you need a kit that can gently process nucleic acids without isolating plasmid DNA. Moreover, the new generation sequencing technology requires high samples, and we also need some special products to purify DNA. Here, we introduce some new options. Master pure(Illumina subsidiary) in the epicenter of salt precipitation method? CompleteDNAPurificationKit adopts patented salt precipitation method. This series of kits covers various sample types, including blood, fixed tissues, plants, yeast, insects and so on. It can bring high yield of nucleic acid in just 30 minutes with little loss. According to CristineKinross, senior product manager of Epicentre, using these kits, users do not need to perform additional purification before preparing samples for sequencing or other molecular biology applications. They can remove protein and other cell debris without introducing toxic compounds that must be removed, thus avoiding repeated washing and improving nucleic acid yield. Kinross said: "The purity of nucleic acid recovered by MasterPure is excellent, which allows samples to directly enter the preparation of sequencing library." Of course, it is also suitable for other applications, including chips, qPCR and cloning. In addition, the kit can also be used for RNA purification. After obtaining the total nucleic acid, the total RNA can be obtained by dnase treatment. Various kits Promega provides various nucleic acid purification kits using several different strategies. Like witches? Based on classical precipitation method, genomic DNA can be extracted flexibly and efficiently from whole blood, tissue culture cells, animal and plant tissues, yeast and bacteria. Where's ReliaPrep? This series of kits adopts column extraction method, which is simple and rapid. In addition, Promega also provides a kit based on magnetic bead purification. EricVincent, global product manager of Promega Genomics, said: "Although the exact composition of the solution will be different, the basic processes of cracking, binding, washing and elution are suitable for different binding methods (such as silica gel or cellulose), different purification forms (purification columns or magnetic beads), and manual and automatic purification operations." For some very important sample types (such as FFPE samples), some special operations or treatments are needed. "We have developed a unique binding/washing buffer, which can effectively remove substances that inhibit downstream reactions, while the optimized system enables researchers to capture a small amount of nucleic acids and elute them in a small volume (less than 30μl), and we have also developed an automated solution suitable for various reagents and fluxes," Vincent said. These kits provide a complete solution, which can elute nucleic acids in a very small volume, while avoiding inhibitors remaining in the eluent. After purification by these kits, nucleic acids can be used for downstream analysis, such as PCR, Sanger sequencing, next generation sequencing and chip. QIAGEN's classic silica gel membrane nucleic acid purification kit relies on the combination of DNA and silica gel membrane on the purification column. The inhibitor was washed away, and the complete DNA was then eluted from the column, with high yield and purity, which brought a new generation of sequencing library with higher quality. Marco Lidori, global product manager of QIAGEN sample preparation, believes that high-yield quantity becomes particularly important when dealing with extremely small samples or difficult samples such as FFPE. Random deamination of cytosine may occur in DNA produced by FFPE samples, which may lead to artificial single nucleotide polymorphism (SNP). However, QIAGEN's GeneReadDNAFFPEKit can remove deaminated cytosine and avoid producing wrong results in NGS experiments. This product has not been officially launched. Please fill in the information if you are interested in trying it out. "Most of our kits have been validated in NGS applications, from genome-wide sequencing of circulating tumor DNA to microbiome," Polidori said. These kits enable users to obtain high-quality DNA from various samples, avoid the C-T illusion of FFPE samples, and obtain high-molecular-weight DNA in a short time. MagAttractHMWDNAkit can purify 100-200kbDNA by simple magnetic bead operation. The whole purification process gently removes pollutants and inhibitors, and the yield and purity are extremely high. GenElute provided by Sigma-aldridge, a chaotropic salt company? Mammaliangenomicpurification kit is a product based on chaotropic salt reagent. In the solution containing chaotropic salt, the sample is cracked to ensure the complete denaturation of macromolecules. Adding ethanol to bind DNA to silica gel membrane. Wash away pollutants and elute DNA in Tris buffer. By specially selecting silica gel membrane for isolating genomic DNA, the kit enables users to purify high-quality DNA from various samples, including cultured cells, tissues (including rat tails), fresh whole blood or white blood cells. According to reports, this kit combines the advantages of silica gel membrane combination and micro-centrifugation, avoiding expensive resin, ethanol precipitation and harmful organic substances such as phenol and chloroform. More importantly, the purified DNA can be used for restriction enzyme digestion, PCR, Southernblot, sequencing and so on. (Author: JamesNetterwald/ Biology Compilation)