Lithium Chloride-Based Isolation of RNA

The extraction of RNA and then isolation of mRNA specifically from the cell homogenate or in vitro transcription reactions can be done easily by lithium chloride (LiCl)-based isolation. This method of RNA isolation is more efficient in precipitating and removing out the unincorporated or smaller fragments of nucleotides. The basic principle involves the interaction between ribose sugar of RNA and positive cations (lithium) to allow the folding and precipitation of RNA only, leaving out the DNA and protein in the aqueous solution. Therefore, there is just simple homogenization of the cell/tissue sample in a suitable buffer, followed by its incubation with LiCl at standardized temperature and pH. The final precipitated RNA can be collected after removing out the aqueous (unprecipitated) sample. In spite of the abovementioned advantages, this technique might not be suitable for isolating the lower concentration of RNAs and different types of RNA other than mRNAs, as evident by the different contradictory studies.