RNA extraction

RNA extraction is the purification of RNA from biological samples. This procedure is complicated by the ubiquitous presence of ribonuclease enzymes in cells and tissues, which can rapidly degrade RNA. Several methods are used in molecular biology to isolate RNA from samples, the most common of these is guanidinium thiocyanate-phenol-chloroform extraction. Usually, the phenol-chloroform solution used for RNA extraction has lower pH, this aids in separating DNA from RNA and leads to a more pure RNA preparation. The filter paper based lysis and elution method features high throughput capacity.

RNA extraction in liquid nitrogen, commonly using a mortar and pestle (or specialized steel devices known as tissue pulverizers) is also useful in preventing ribonuclease activity.