Nanofiber adsorbents for high productivity downstream processing

Abstract

Electrospun polymeric nanofiber adsorbents offer an alternative ligand support surface for bioseparations. Their non-woven fiber structure with diameters in the sub-micron range creates a remarkably high surface area. To improve the purification productivity of biological molecules by chromatography, cellulose nanofiber adsorbents were fabricated and assembled into a cartridge and filter holder format with a volume of 0.15 mL, a bed height of 0.3 mm and diameter of 25 mm. The present study investigated the performance of diethylaminoethyl (DEAE) derivatized regenerated cellulose nanofiber adsorbents based on criteria including mass transfer and flow properties, binding capacity, and fouling effects. Our results show that nanofibers offer higher flow and mass transfer properties. The non-optimized DEAE-nanofiber adsorbents indicate a binding capacity of 10% that of packed bed systems with BSA as a single component system. However, they operate reproducibly at flowrates of a hundred times that of packed beds, resulting in a potential productivity increase of 10-fold. Lifetime studies showed that this novel adsorbent material operated reproducibly with complex feed material (centrifuged and 0.45 µm filtered yeast homogenate) and harsh cleaning-in-place conditions over multiple cycles. DEAE nanofibers showed superior operating performance in permeability and fouling over conventional adsorbents indicating their potential for bioseparation applications.

In situ cross-linked and highly carboxylated poly(vinyl alcohol) nanofibrous membranes for efficient adsorption of proteins

“…The K d represents an important aspect of sorbent's performance metrics of proteins adsorption, and K d values of 1 × 10 5 ml g -1 are usually considered excellent. 18,28,40 Conspicuously, the fast adsorption equilibrium endows the PVA/MAH nanofibrous membranes with potential to constitute a adsorptive membrane/chromatography for practical purification of proteins in the future. It's worth noting that further increasing the MAH content would not bring higher adsorption capacity, this phenomenon could be understandable considering that the superfluous MAH was encapsulated into the PVA fibers and could not undergo esterification to form terminal carboxyl groups to adsorb lysozyme, consequently, the adsorption capacity barely changed.…”

“…nucleic acid, exotoxin, and proteins carry different charge), enables purify different species of proteins, and cost-effective when compared with the aforementioned approaches. 18 Therefore, utilizing nanofibrous membranes to create adsorptive fibrous membranes has been suggested as a potential alternative approach to achieve promising protein adsorption performance. 15,16 Traditionally, the porous resin beads or gel microspheres containing surface functional groups have commonly been packed into chromatography columns to capture selected species from mixtures in biotechnological and biopharmaceutical industry.…”

Adapting viral safety assurance strategies to continuous processing of biological products

“…Recent advances in electrospun nanofiber adsorbents offer improved properties over traditional membrane adsorbers with a larger surface area in relation to their pore size which makes them easily suited to the manufacturing of monoclonal antibody products (Bilad et al, ). This approach provides a general increase in productivity over traditional membrane or packed bed media in either batch or continuous downstream processing (Hardick et al, , ). Nanofiber adsorbents, such as electrospun chitosan fibers, have already been proven to clear viruses in water purification systems (Mi and Heldt, ; Mi et al, ), and further research would elucidate their applicability in bioprocessing viral clearance claims.…”

Adapting viral safety assurance strategies to continuous processing of biological products

“…Recent advances in electrospun nanofiber adsorbents offer improved properties over traditional membrane adsorbers with a larger surface area in relation to their pore size which makes them easily suited to the manufacturing of monoclonal antibody products (Bilad et al, 2011). This approach provides a general increase in productivity over traditional membrane or packed bed media in either batch or continuous downstream processing (Hardick et al, 2013(Hardick et al, , 2015. Nanofiber adsorbents, such as electrospun chitosan fibers, have already been proven to clear viruses in water purification systems , and further research would elucidate their applicability in bioprocessing viral clearance claims.…”