Nonwoven Ion-Exchange Membranes with High Protein Binding Capacity for Bioseparations

Abstract

This study presents the preparation and characterization of UV-grafted polybutylene terepthalate (PBT) ion exchange nonwoven membranes for chromatographic purification of biomolecules. The PBT nonwoven was functionalized with sulfonate and secondary amine for cation and anion exchange (CEX and AEX), respectively. The anion exchange membrane showed an equilibrium static binding capacity of 1300 mg BSA/g of membrane, while the cationic membranes achieved a maximum equilibrium binding capacity of over 700 mg hIgG/g of membrane. The CEX and AEX membranes resulted in dynamic binding capacities under flow conditions, with a residence time of 0.1 min, of 200 mg hIgG/mL of membrane and 55 mg BSA/mL of membrane, respectively. The selectivity of the PBT-CEX membranes was demonstrated by purifying antibodies and antibody fragments (hIgG and scFv) from CHO cell culture supernatants in a bind-an-elute mode. The purity of the eluted samples exceeded 97%, with good log removal values (LRV) for both host cell proteins (HCPs) and DNA. The PBT-AEX nonwoven membranes exhibited a DNA LRV of 2.6 from hIgG solutions in a flow-through mode with little loss of product. These results indicate that these membranes have significant potential for use in downstream purification of biologics.

Iminodiacetic Acid (IDA) Cation-Exchange Nonwoven Membranes for Efficient Capture of Antibodies and Antibody Fragments

“…Due to the higher binding capacity obtained by linking IDA onto the membranes at pH 10.0, we employed this reaction condition for the studies that followed. Prior work in our lab [ 34 , 42 ] indicated that ion-exchange membranes prepared by grafting polyGMA at 20% WG showed higher protein-binding capacity while maintaining excellent flow permeability. As a result, all CEX-IDA membranes used in the following studies were prepared based on 20% WG polyGMA grafted membranes.…”

“… 1 For the two membrane types, the experiments were performed using the same conditions with 12 membrane layers packed in a 12 cm diameter column. All details of CEX-SO 3 membrane experiments are reported in [ 34 ]. …”

“…The results were membranes that exhibited high protein-binding capacity and a significant potential to realize single-use membrane capture chromatography [ 28 , 33 ]. In our previous work, a strong cation-exchange (CEX) membrane with sulfonic acid as ligand (CEX-SO 3 membrane) was fabricated based on a PBT nonwoven and exhibited an excellent protein-binding capacity of 712.9 mg human polyclonal immunoglobulin G (hIgG)/per g of membrane at equilibrium [ 34 ]. It is well known that the sulfonate group is very stable and completely ionized over a wide pH range, while the carboxyl group commonly has weak cation-exchange ligands with variable ionization depending on the solution pH, and this can generate selectivity results that are different from those of strong cation-exchange ligands [ 35 , 36 ].…”

Thermal Degradation Kinetics Analysis of Polymer Composite Electrolyte Membranes of PEVOH and PBT Nano Fiber

“…It can be processed by several available techniques and is readily dissolvable in methylene chloride. This creates a possible route for electrospinning into microporous non-woven structures [ 23 , 24 ]. The porous polymer composites are very important and have been widely used in many practical applications, such as fibrous porous media [ 25 ].…”

Membrane and Membrane Bioreactors Applied to Health and Life Sciences

“…Membrane ion-exchange chromatography promises several advantages over column chromatography, including low operating pressure and fast flow rates, ease of use, and elimination of cleaning and validation costs in single-use applications. To this end, Lemma et al [4] developed and characterized ion-exchange nonwoven membranes for the chromatographic purification of biomolecules. UV-grafted polybutylene terepthalate were prepared and functionalized with sulfonate and secondary amine for cation and anion exchange, respectively.…”