Phenol-based reagent for the isolation of total RNA and DNA from cells and tissues.

The method is based on the extraction of nucleic acids aqueous solutions using organic solvents. After homogenizing the sample with RNA Extracol, chloroform (or 1-bromo-3-chloropropane) is added, and the homogenate is allowed to separate into a clear upper aqueous layer, an interphase, and a lower organic layer. Separation of nucleic acids between the phases is pH dependent. At pH 4-6 DNA passes into the organic phase while RNA remains in the aqueous phase (containing RNA). The highly effective RNase inhibitory property of RNA Extracol protects the integrity of the RNA during lysis and results in the isolation of high-quality material. RNA is precipitated from the aqueous layer with isopropanol. The precipitated RNA is washed to remove impurities and then resuspended for use in downstream applications.