Protein–polymer interaction: Transfer loading at interfacial region of PES‐based membrane and BSA

Abstract

The adsorption of proteins onto polymeric surfaces is encountered in many natural and industrial processes and is a prerequisite to their efficient identification, separation, and purification by methods such as chromatography, and filtration. Nevertheless, the exact nature of the adsorption mechanisms and interfacial interactions is not easy to identify for a given protein-polymer system. Here, we aim to document the adsorption mechanism of a protein-polymer system by investigating the adsorption as well as desorption phenomenon of a protein [bovine serum albumin (BSA)] from the polymeric surface [polyethersulfone (PES)]. The analyses performed to document the adsorption mechanism of the BSA-PES system include scanning electron microscope (SEM), attenuated total reflection-Fourier transform infrared (FTIR), contact angle, zeta potential, surface charge density measurement, and Derjaguin-Landau-Verwey-Overbeek (DLVO). Here, SEM and FTIR identified the physical and chemical properties of pure PES and PES-BSA membranes. The low water contact angle of the PES-BSA membrane confirms its applicability for tissue engineering applications. Further, the zeta potential, surface charge density measurement, and DLVO analyses were performed to document the adsorption mechanism. The adsorption of BSA particles on the PES surface was carried out for pH values that ranged from 4 to 10 for contact times that ranged from 1 to 3 days. A monotonic increase in the zeta potential of the PES-BSA system indicated considerable adsorption of BSA particles on the PES surface. Further, BSA adsorption was very strong for pH values greater than 4.7 which confirms to strong electrostatic interactions between BSA and PES. The strong electrostatic interaction is also collaborated by low desorption rate, which was only 22% for pH 10 after 3 days of contact.

Improving Membrane Filtration for Copper Speciation: Optimal Salt Pretreatments of Polyethersulfone Membranes to Prevent Analyte Retention

“…For the small protein aprotinin (6.5 kDa), this would be 1.5–7.7 nmol for a membrane area of 0.5 cm 2 . This amount would be in the same molar range we observed for the much smaller cation Cu 2+ , even if the adsorption of proteins to PES membranes is far more complex . However, if very low concentrations of toxic metal ions like Cu 2+ in μg L –1 range (e.g.…”

“…This amount would be in the same molar range we observed for the much smaller cation Cu 2+ , even if the adsorption of proteins to PES membranes is far more complex. 53 However, if very low concentrations of toxic metal ions like Cu 2+ in μg L –1 range (e.g. up to 500 μg L –1 ) are of interest, the observed membrane retention may strongly bias the assessment of the environmental risk.…”

Study on Cubic-Orientation Settlement of Angiotensin Converting Enzyme II Immobilized on Polystyrene by Molecular Dynamics Simulation

“…The adsorption of protein on polymer has been widely reported [36][37][38][39][40][41] as summarized in Table 1. The protein adsorption mechanism mainly focuses on one or more of van der Waals (VDW), electrostatic and hydrophobic interactions.…”

“…There was no direct correlation between the adsorption capacity of BSA and HSP, and the immobilized BSA was increased with increasing VDW component of surface tension. The comprehensive characterization of BSA on polyethersulfone (PES) surface was conducted by scanning electron microscope (SEM), attenuated total reflection-Fourier transform infrared (FTIR), contact angle, zeta potential [38]. Surface charge density measurement showed that the adsorption of BSA on PES was irreversible at pH > 4.7 due to the strong electrostatic interaction between BSA and PES.…”