Formation of peptide layers and adsorption mechanisms on a negatively charged cation-exchange membrane

Fouling prevention of peptides from a tryptic whey hydrolysate during electromembrane processes by use of monovalent ion permselective membranes

“…Concerning the cationic membranes, fouling was the highest at pH 6, lower at pH 2 and none at pH 10 for both permselective MCP and conventional CMX-SB 10 . Once again, peptide fouling was really low with a total relative abundance of peptides for MCP decreased of about 95-100 % lower compared to CMX-SB ( Figure 3).…”

“…5) and R (pKa=12.5) residues which interacted electrostatically with the negative groups of the CMX-SB and MCP membranes (Table 7) as explained in details for cation-exchange membranes by Persico et al 10 . Figure 4: Nitrogen content coming from fouled peptides on the different membranes compared with already published data in static conditions (Adapted from 9,10 ) This decrease in fouling for permselective MAP and MCP membranes is due to the presence of a thin layer oppositely charged with their respective matrix. Indeed, a fluorescence capture using a positively charged rhodamine B of the MCP surface is shown and compared with CMX-SB ( Figure 5).…”

“…Recent studies showed that conventional food-grade anion-exchange membranes (AMX-SB) and/or cation-exchange membranes (CMX-SB) are exposed to fouling in presence of a WPH either in static 9,10 or in hydrodynamic conditions during an ED process 11 . Fouling was mainly due to a few peptides which could establish electrostatic interactions with the membranes, and that even with no current applied.…”

“…(3) to compare that fouling in terms of quantity and peptide sequences with the conventional membranes from previous studies 9,10,11 carried-out with the same WPH and in the same static and ED conditions.…”

Recent insights into structure-function relationships of antimicrobial peptides

“…Besides, large‐scale fractionation and purification of AMPs still a challenge for the industry, with fouling of separation membrane being the most frequent problem. Recently, peptide aggregation to anion and cation‐exchange membranes was reported to involve electrostatic interactions and to be influenced by pH of the solution and charges distribution at the surface of the macromolecular structures (Persico et al, ).…”