Vibration-assisted ultrafiltration dramatically improves mRNA purification

The development of high-quality messenger RNA (mRNA) products depends critically on the development of effective methods for purification and formulation of these gene therapies. Conventional ultrafiltration processes have been successfully used for mRNA concentration, but membrane fouling and shear-induced mRNA degradation can limit their effectiveness. This study provides the first demonstration of Vibro Membrane Filtration (VMF) to perform vibration-assisted single pass tangential flow filtration (SPTFF) for the concentration and purification of mRNA produced by in vitro transcription. Data were obtained using 100 kDa polyethersulfone membranes using two mRNA constructs with very different sizes. The sustainable flux, protein removal, and extent of fouling were evaluated in the presence and absence of vibration. The vibration significantly reduces concentration polarization leading to an increase in the sustainable flux, a reduction in membrane fouling, and better mRNA purification. The VMF was able to provide continuous operation for 24 hr with 10X concentration factor without any loss in mRNA integrity. These results demonstrate the exciting potential of using VMF for the continuous and / or intensified bioprocessing of mRNA therapeutics.