NZY Total RNA Isolation kit is designed for the easy purification of total RNA of highest integrity (longer than 200 bases) from a variety of sources such as animal tissues, bacteria cells and cell cultures. This method uses a denaturing lysis buffer containing guanidine thiocyanate, which inactivates cellular RNases, to ensure the recovery of intact RNA molecules. Ethanol is added to provide selective binding of total RNA into the silica membrane column and impurities are efficiently washed away. To prevent the contamination with DNA, a DNase I solution is directly added onto the silica membrane of the binding column. High-quality RNA is then eluted in RNase-free water.