The architecture of responsive polymeric ligands on protein binding and recovery

Abstract

Ligand design and optimization are critical for protein purification during downstream processing.

Electrospun Weak Anion-Exchange Fibrous Membranes for Protein Purification

“…However, resin-based packed-bed chromatography suffers from high pressure drop and slow pore diffusion which leads to longer processing time and potentially denaturation of the product. Membrane adsorbers are promising technologies to replace resin-based chromatography [8][9][10][11][12][13][14]. Membrane-based IEX and HIC adsorbers can overcome afore-mentioned limitations [15,16].…”

“…However, membrane capacity is typically lower compared to that of resin. Significant efforts have been dedicated to develop high binding capacity and/or high recovery membrane adsorbers by grafting ligands on membrane substrates using UV-initiated polymerization or atom-transfer radical polymerization (ATRP) [8][9][10][11][12][13][14][17][18][19].…”

“…Previous studies [24][25][26][27] conjugated a monomeric acid, base or affinity ligand directly to the functional group on the substrate. However, there has been significant work [8][9][10][11][12][13][14][17][18][19] on surface modification by grafting polymers on the flat sheet membrane substrates using ATRP and UV-initiated polymerizations. These results show that there exists an optimal ligand chain density and chain length for maximizing protein binding capacities for IEX, affinity and HIC membrane chromatography [19].…”

“…At relatively low grafting degree,~100 mg/mL protein binding capacity of BSA can be obtained. Besides ligand, substrate morphology and porosity also play an important role [11]. Previous work [30] investigated the effects of degree of glycidyl methacrylate (GMA) grafting of non-woven substrate on the kinetics of non-specific protein adsorption.…”

Ion-specificity in protein binding and recovery for the responsive hydrophobic poly(vinylcaprolactam) ligand

“…A new class of salt-and temperature-responsive ligands that can switch hydrophobic and hydrophilic conformation under different buffer conditions has been explored for HIC applications using buffers containing (NH 4 ) 2 SO 4 or NaCl only. [7][8][9][10] As the degree of hydration and dehydration of these temperature/salt ion responsive ligands is highly salt ion and salt concentration specic, the effects of salt ion type and salt ion concentration on protein-responsive ligand binding are investigated. Here we focus on poly(vinylcaprolactam) (PVCL) which exhibits higher binding capacity than other responsive ligands.…”