New Oligo dT resins for mRNA purification and isolation: exploring new technology based on seeded magnetic beads and jetted styrene/DVB resins

The new Sunresin Seplife®Oligo dT affinity resin is designed for the purification and isolation of mRNA from in vitro transcription (IVT) manufacturing processes. Using the 20 years experience of Sunresin in manufacturing specialty resins, we have designed a unique technology that manufactures a 50 micron polymeric resin with very uniform particle sizes by seed swelling. The resin is a crosslinked polystyrene divinylbenzene resin functionalized with oligo dT20. The resin effectively captures mRNA from components of the transcription reaction process, such as enzymes and plasmid DNA.

Seplife® Oligo dT has been designed to fulfill the increasing demand in selectivity, capacity and large scale downstream purification of a range of mRNA constructs used in vaccine, such as mRNA COVID-19 vaccine , oncology vaccines, AIDS vaccines, treatment and prevention of  rare diseases and other major diseases. This resin allows to selectively captures the mRNA via the polyadenylated (polyA) tail using simple salt (0.5M NaCl) and water-based purification steps.

The main features of Oligo dT combine easy mRNA purification from crude transcription mix to effectively remove plasmid DNA and other IVT components, simplified workflow thanks to easy adaptation to different kind of columns and excellent scalability. Of course, the resin has been designed to show excellent stability to temperature up to 65℃ and to alkali for efficient CIP.

The unique resin technology developed by Sunresin allows to manufacture resin batches of 50Kg, thus decreasing the risk on variability and best in class manufacturing capabilities using GMP conditions and strict QC controls.

The surface of the resin microspheres is modified – using a proprietary technology - to become more hydrophilic in order to reduce non-specific adsorption. This is achieved by addition of a ligand made of a long chain spacer arm, so the steric hindrance is reduced, the mass transfer rate is increased, and the high dynamic binding is ensured. The surface of the beads is then functionalized with poly(dT) to allow the capture of mRNA though base pairing with the mRNA polyA tail.

In this poster we present applications in the purification of 1200nt mRNA using Oligo dT using capture and release under standard mRNA purification conditions. In addition, the coating performed on the resin allows reduction in plasmid DNA and other transcription mix components.

We also present the newly developed magnetic resins functionalized with oligo dT for easy purification and separation in R&D development stages. These magnetic beads start from a core resin of  polystyrene divinylbenzene made  by a unique seeding technology that allows to make monosized beads from  1 to 3 micron. These beads are then coated with Fe3O4 and then fully coated with a polyurethane shell that fully protects the beads from releasing the paramagnetic material.

These magnetic particles allow easy and fast separation of mRNA so the process of developing and screening of new gene therapies is enhanced.