Separation of Nucleic Acids Using Single- and Multimodal Chromatography

The needs for purified nucleic acids for preparative and analytical applications have increased constantly, demanding for the development of new and more efficient methods for their recovery and isolation. DNA molecules harbour some intrinsic chemical properties that render them suitable for chromatographic separations. These include a negatively charged phosphate backbone as well as a hydrophobic character originating mainly from the major groove of DNA which exposes the base pairs on the surface of the molecule. In addition, single stranded DNA often allows for a free exposure of the hydrophobic aromatic bases. In this review, multimodal chromatography (MMC) has been evaluated as an alternative tool for complex separations of nucleic acids. MMC embraces more than one kind of interaction between the chromatographic ligand and the target molecules. These resins have often proved superior to conventional single-mode chromatographic materials for DNA isolation, including, e.g., the purification of plasmid DNA from crude cell lysates and for the preparation of DNA fragments before or after a polymerase chain reaction (PCR).