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ABSTRACT Technologies for large‐scale manufacturing of viral vectors for gene therapies, such as tangential flow filtration and membrane chromatography, are under development. In these early stages of process development, techno‐economic analyses are useful for identifying membrane properties yielding the greatest impact on process performance. In this study, we adapted a techno‐economic framework used for monoclonal antibody capture for adeno‐associated viral vector purification. We added mechanistic models to simulate flux decline during harvesting and separating full and empty capsids during polishing. Graphical user interfaces were added to help users explore the design search space. We selected a base process and manipulated selected variables to see their impact on large‐scale manufacturing performance. These sensitivity analyses revealed that, under the selected process conditions, increasing module capacity reduces cost of goods more effectively than increasing operational flux in tangential flow membrane filtration modules for virus harvesting. Membrane chromatography columns with relatively low dynamic binding capacity (DBC) and short residence time (RT) offered similar or better economic performance than those with high DBC and long RT. Additionally, the difference in equilibrium solid‐phase concentration between full and empty capsids as a function of salt concentration significantly affects purity.
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Tangential Flow Microfluidics for the Capture and Release of Nanoparticles and Extracellular Vesicles on Conventional and Ultrathin Membranes
Abstract Membranes have been used extensively for the purification and separation of biological species. A persistent challenge is the purification of species from concentrated feed solutions such as extracellular vesicles (EVs) from biological fluids. Investigated is a new method to isolate micro‐ and nanoscale species termed tangential flow for analyte capture (TFAC), which is an extension of traditional tangential flow filtration. Initially, EV purification from plasma on ultrathin nanomembranes is compared between both normal flow filtration (NFF) and TFAC. NFF results in rapid formation of a protein cake which completely obscures any captured EVs and also prevents further transport across the membrane. On the other hand, TFAC shows capture of CD63 positive small EVs with minimal contamination. The use of TFAC to capture target species over membrane pores, wash, and then release in a physical process that does not rely upon affinity or chemical interactions is explored. This process is studied with model particles on both ultrathin and conventional thickness membranes. Successful capture and release of model particles is observed using both membranes. Ultrathin nanomembranes show higher efficiency of capture and release with significantly lower pressures indicating that ultrathin nanomembranes are well‐suited for TFAC of delicate nanoscale particles such as EVs.
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- Award ID(s):
- 1660177
- PAR ID:
- 10372418
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 4
- Issue:
- 11
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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