The Solar miRNA Isolation Kit uses a rapid procedure to isolate small RNAs, such as microRNA (miRNA), small interfering RNA (siRNA), and small nuclear RNA (snRNA), from wide range of tissues and cells. The fast and efficient silica membrane based method isolates total RNA ranging in size from kilobases down to 10mers. The kit also provides reagents and a procedure to enrich the population of RNAs that are 200 bases and smaller, which enhances the sensitivity of small RNA detection by solution hybridization, Northern analysis, and other methods.