To obtain nucleic acid, the basic steps include: cell lysis—nucleic acid precipitation—nucleic acid washing—elution. After the cell lysis step, the nucleic acid precipitation can be performed either with alcohol precipitation or matrix adsorption method. Nucleic acids are water-soluble polyanions, and their sodium and potassium salts are insoluble in most organic solvents, including ethanol water mixtures, but they will not be denatured by organic solvents at medium concentrations of monovalent cations (NaCl, NaAc, NH₄AC). Therefore, organic solvents such as ethanol and isopropanol are commonly used as precipitators for nucleic acids. It is then centrifuged and redissolved in a suitable buffer at the desired concentration.

TIANGEN’s precipitation-based genomic DNA extraction kits adopt unique buffer system to extract genomic DNA with high quality and high purity.