Purification of monoclonal antibodies in a stirred cell with polyethyleneimine‐modified polyethersulfone ultrafiltration membrane

Abstract

BACKGROUND: Charged ultrafiltration membranes combined with optimal operating conditions can be used to enable monoclonal antibody purification. Positively charged ligands bound to the membrane surface can significantly contribute to the adsorption of negatively charged proteins and enhance the purification process. RESULTS:In this work, commercially available 500 kDa polyethersulfone ultrafiltration membranes were modified by sulfonation, followed by deposition of polyethyleneimine (PEI) and crosslinking with butanedioldiglycidylether. Polymer molecules of 2 and 10 kDa were used to evaluate how polymer size influences the fractionation of a harvested Chinese hamster ovary cell culture fluid containing a monoclonal antibody by ultrafiltration at different operational pH values. The precursor and modified membranes were analyzed by X-ray photoelectron spectroscopy, which confirmed the successful modification of membranes. Nitrogen analysis showed the presence of amine groups, clearly confirming immobilization of PEI onto the membrane surface. When 10 kDa PEI is chosen for membrane modification, the intensity of this signal increases, as predicted for a higher-molecular-weight polymer. Ultrafiltration performance indicators (fluxes, transmissions, yields) were determined and compared for the modified and precursor membranes, with the PEI-derived membranes showing ability for pH modulation of selectivity.CONCLUSION: High purities were consistently observed at pH 9 owing to a simultaneous decrease in the transmission of soluble protein and increase in both IgG transmission and adsorptive capacity of the membranes. A single-step process at pH 9 renders a permeate with an antibody purity of 96%, using a non-crosslinked membrane modified with 10 kDa PEI.

Impact of Tween‐80 and Deep Eutectic Solvent‐Based Micellar‐Enhanced Ultrafiltration in Dairy Wastewater Treatment

“…The pH of dairy effluent should be neither low nor high due to the usage of acid or alkaline detergents in the dairy plant cleaning process, leading to the breakdown of organic components. By reducing the organic and inorganic pollutants from the effluent, the pH value can be made neutral for further usage 40.…”

“…Treating the dairy effluent resulted in a low EC value, which is eight times lower than the initial value. This is found to be under the permissible limit of 1400 mS cm -1 recommended by the World Health Organization (WHO) for discharging [40].…”

“…The pH of dairy effluent should be neither low nor high due to the usage of acid or alkaline detergents in the dairy plant cleaning process, leading to the breakdown of organic components. By reducing the organic and inorganic pollutants from the effluent, the pH value can be made neutral for further usage [40]. The electrical conductivity (EC) of as-treated dairy wastewater is in the range of about 0.55 mS cm -1 , while in the wastewater treated with the DES-3 membranes, the EC value decreased from 0.55 to 0.068 mS cm -1 .…”

Intensified Downstream Processing of Monoclonal Antibodies Using Membrane Technology

“…In recent work, Wagner (2019) demonstrated purification of an IgG molecule through selective retention of negatively charged impurities from a CHO cell culture supernatant by using a polyethyleneimine modified membrane carrying positive ligands on their surface. [ 95 ] Even though this study was performed using cell culture supernatant, the phenomenon of selective retention owing to charged surfaces could be applied to the final pre‐formulation step for mAbs.…”

Robust water‐stable poly (ethersulfone)/poly (ethyleneimine) nanofibrous membranes for nitrate adsorption

“…16,17 Polyethyleneimine (PEI), branched and hyperbranched PEI, PEI grafted silica, and tetraethylorthosilicate are some of the additives used to improve hydrophilicity, selectivity, and antifouling of PES substrate. [18][19][20][21] Nanofibrous webs are good candidates for membranes due to their excellent interconnected porous structure and small pore size. 22,23 Chemical or physical modification of the nanofibrous webs could increase their efficiency and lead to a high specific surface area membrane with many adsorbents between its pores.…”