Advances in chromatographic supports for pharmaceutical-grade plasmid DNA purification.

Chromatographic technology is undoubtedly one of the most diverse and powerful purification methods for downstream process applications. The diversity and quantity of biomolecules present in crude extracts as well as the similarities between impurities and the target biomolecule are considered the critical challenges in the extraction and purification steps. Thus, it is important to optimize the purification protocol to achieve maximum recovery of the target sample. The structure of chromatographic supports has been continuously developed to afford rapid and efficient separations, as well as, the application of specific ligands to improve the selectivity for the target molecule. The present review discusses the structural progress and evolution of the chromatographic supports that have been used for plasmid DNA purification. Nowadays, the most desirable form of plasmid for gene therapy and DNA vaccination is the supercoiled isoform, due to its stability and higher transfection efficiency over other plasmid topologies. However, the main challenge is not only to produce high quantities of supercoiled plasmid DNA but also to preserve its quality, meeting the strict requirements recommended by the regulatory agencies. Therefore, this review will focus on the chemical and structural classification of the different media and on some of the specific ligands used for plasmid DNA bioseparation.