DNA/RNA Extraction and Precipitation

This chapter presents a method for DNA/RNA extraction and precipitation. This method involves the removal of protein and contaminants from samples of DNA or RNA prior to use. For this purpose, an SS-phenol/chloroform extraction of protein is followed by ethanol precipitation. The preparation for extraction and precipitation involves an aqueous solution of known volume of the aforementioned sample. The sample is mixed with equal volumes of SS-phenol and chloroform. After vortexing the sample, the upper aqueous layer is removed and subjected to ethanol precipitation. In the steps that follow, residual salt is removed by vortexing, the supernatant is discarded, and the pellet is allowed to air-dry.