Streamlining mRNA Purification with Tangential Flow Filtration (TFF)
As mRNA-based vaccines and therapies continue to proliferate, the downstream purification process, particularly Tangential Flow Filtration (TFF), has become a critical efficiency and cost focus. Yet, data on optimizing TFF for mRNA is notably scarce, complicating process development.
Researchers from the University of Sheffield led by Dr. Zoltán Kis and Ehsan Nourafkan have broken new ground by experimentally modeling TFF’s performance in purifying mRNA from unreacted nucleoside triphosphates (NTPs) in in vitro transcription mixtures.
Key Findings
- Running TFF at ~19 g/m² loading with transmembrane pressure below 2.5 psi and a feed flux of 300 L/m²/h (LMH) yielded:
- No detectable mRNA degradation
- Complete nucleoside triphosphates (NTP) removal
- ~30 percent mRNA loss which was dramatically reduced to just ~3 percent using two sequential membrane wash steps
- For concentration steps (with mRNA <1 mg/mL) operating at permeate flux <40 LMH helped maintain stable transmembrane pressure and minimize fouling. Meanwhile higher fluxes benefited diafiltration performance.
By fitting fouling behaviors to models like the Hermia model, the team could predict transmembrane pressure trends over time which facilitates better scheduling for TFF filter cleaning or replacement.
Why This Matters
This research helps fill a pressing knowledge gap in mRNA bioprocessing. By offering quantitative guidance on filtration pressures flux rates fouling dynamics and recovery efficiencies the study enables more robust scalable and cost-efficient mRNA purification workflows.
These insights are especially valuable as the industry moves toward production scale where minimizing product loss and maximizing throughput are critical.
References
Nourafkan E, Kis Z. Optimizing tangential flow filtration for mRNA filtration. Genetic Engineering and Biotechnology News. 2024 Dec 18. Available from: https://www.genengnews.com/topics/bioprocessing/optimizing-tff-for-mrna-filtration
