Purification of mRNA with CIMmultus® Oligo dT
The ligand in CIM® Oligo dT18 is an 18-mer deoxythymidine chain covalently immobilised on the monolith with a carbon linker. RNA with a poly(A) tail binds on the ligand by hybridisation between adenine (A) bases on the RNA tail and deoxythymine (T) bases of the ligand. Species which do not contain a poly(A) tail do not bind on the column and are found in the unbound (flow through) fraction. CIM® Oligo dT18 can be used for purification or analytics or ssRNA, including RNA exceeding 10 kb (self-amplifying RNA). In a purification process, it is most often employed for capture of RNA in crude samples such as IVT reaction mixtures.
The sample is applied at elevated ionic strength to suppress charge repulsion between the phosphatidic acid residues on the ligand and the target RNA. RNA is recovered by reducing ionic strength, which restores charge repulsion sufficiently to dissociate the hydrogen bonds.