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Hemodialysis (HD) membrane materials-blood hemocompatibility is considered as the most important reason for intra- and post hemodialysis complications. The incompatibility could result in different cascade activations due to the interactions between vital human serum proteins (HSPs) and HD membranes. This study aims to assess the interaction energy between common hemodialysis polymer structures in the zwitterionized state and HSPs using molecular dynamics (MD) simulation to offer a framework for understanding the dominant interactions as a reference for HD material development. To perform zwitterionization, a feasible mussel-inspired methodology was used. Poly aryl ether sulfone (PAES) and cellulose triacetate (CTA) were chosen for the base membrane models and carboxybetaine methacrylate (CBMA), sulfobetaine methacrylate (SBMA), and phosphobetaine methacrylate (PBMA) were picked as common zwitterionic structures (ZWs) for surface modification. Human serum albumin (HSA), fibrinogen (FB), and transferrin (TRF) were selected as the models of HSPs. Polydopamine (PDA) was used for the binding structure. The binding energy of the membrane models and selected proteins, as well as the hydrophilicity of the membrane models, was assessed. Hydrophilicity assessment of the membrane models suggests that PBMA creates more tendency to water molecules when the modifying layer is located on both CTA- and PAES-based membrane models. The results suggest that the hemocompatibility of the membranes does not directly correlate with the hydrophilicity of the polymeric structures. While each protein creates a specific trend when interacting with membrane models with different base polymers and modifying layers, natural biomolecules such as PDA or carboxybetaine structures are suggested to eliminate FB's interactions. For biocompatibility enhancement, as well as hydrophilicity enhancement, sulfo- and phosphobetaine-containing coatings could be used. [ABSTRACT FROM AUTHOR]

End stage renal disease (ESRD) affects ≈10% of the world's population. Hemodialysis (HD) is a life‐sustaining extracorporeal blood purifying treatment for ESRD patients. Despite the advances in technology, the hemoincompatibility of the dialyzers leads to a high morbidity and mortality rate. Decreasing interactions between polymers and blood constituents will result in controlled binding of human serum proteins to the surface and consequently enhanced biocompatibility. This study aims to assess the interaction energy between common hemodialysis polymer structures and human serum proteins using molecular dynamics simulation to offer a framework for understanding the dominant interactions as a reference for material development. Molecular dynamics and molecular docking simulations are conducted for calculating polymerprotein binding energies. Common serum proteins are selected for protein models. Poly aryl ether sulfone (PAES) with and without polyvinyl pyrrolidone (PVP), polyvinylidene fluoride (PVDF), cellulose triacetate (CTA), polyacrylonitrile (PAN), and polymethyl methacrylate (PMMA) membrane structures are chosen as the different classes of dialyzers. The van der Waals interactions between polymers and proteins dominate the binding energies sequence. Molecular docking results of the affinity between protein receptors‐ligands are aligned with the MD binding interaction. [ABSTRACT FROM AUTHOR]

Despite advances in the field, hemoincompatibility remains a critical issue for hemodialysis (HD) as interactions between various human blood constituents and the polymeric structure of HD membranes results in complications such as activation of immune system cascades. Adding hydrophilic polymer structures to the membranes is one modification approach that can decrease the extent of protein adsorption. This study conducted molecular dynamics (MD) simulations to understand the interactions between three human serum proteins (fibrinogen [FB], human serum albumin, and transferrin) and common HD membranes in untreated and modified forms. Poly(aryl ether sulfone) (PAES) and cellulose triacetate were used as the common dialyzer polymers, and membrane modifications were performed with 2‐hydroxymethyl methacrylate (HEMA) and poly (2‐methoxyethyl acrylate) (PMEA), using polydopamine‐assisted co‐deposition. The MD simulations were used as the framework for binding energy simulations, and molecular docking simulations were also performed to conduct molecular‐level investigations between the two modifying polymers (HEMA and PMEA) and FB. Each of the three proteins acted differently with the membranes due to their unique nature and surface chemistry. The simulations show PMEA binds less intensively to FB with a higher number of hydrogen bonds, which reflects PMEA's superior performance compared to HEMA. The simulations suggest PAES membranes could be used in modified forms for blood‐contact applications as they reflect the lowest binding energy to blood proteins. [ABSTRACT FROM AUTHOR]

Proteins in dairy streams result in organic fouling and function loss for ceramic membrane's porous structure. Synchrotron‐based X‐ray microtomography (SR‐µCT) is a new method with a high signal to noise ratio and accordingly significant level of accuracy. The goal of this study was to perform an in situ assessment of ceramic membrane fouling in the dairy stream filtration process, using SR‐µCT. This study attempted to assess porosity variation and membrane fouling through different layers from the top, middle, and bottom layers of the ceramic microfiltration membrane before and after skimming milk filtration. Molecular dynamics simulation (MDS) was used for depth understanding of milk protein interactions with the ceramic membrane. Fouling was found to be more intense on the top of the ceramic membrane even though the top layer was slightly more porous, which indicates that top layers were more prone to fouling. A regression model was derived to correlate the porosity loss due to membrane fouling at different membrane thicknesses. The MDS results showed more affinity of the milk proteins to the ceramic membrane compared to water molecules. The MDS studies showed how the presence of the milk's protein macromolecules could change the hydrophilicity trend on the membrane's surface. [ABSTRACT FROM AUTHOR]

Computational frameworks have been under specific attention within the last two decades. Molecular Dynamics (MD) simulations, identical to the other computational approaches, try to address the unknown question, lighten the dark areas of unanswered questions, to achieve probable explanations and solutions. Owing to their complex microporous structure on one side and the intricate biochemical nature of various materials used in the structure, separative membrane materials possess peculiar degrees of complications. More notably, as nanocomposite materials are often integrated into separative membranes, thin-film nanocomposites and porous separative nanocomposite materials could possess an additional level of complexity with regard to the nanoscale interactions brought to the structure. This critical review intends to cover the recent methods used to assess membranes and membrane materials. Incorporation of MD in membrane technology-related fields such as desalination, fuel cell-based energy production, blood purification through hemodialysis, etc., were briefly covered. Accordingly, this review could be used to understand the current extent of MD applications for separative membranes. The review could also be used as a guideline to use the proper MD implementation within the related fields. [Display omitted] • Overview of molecular dynamics simulation for membrane separation and porous materials. • MD-driven Initial Parameters. • Contribution of Computational Tools to Different Membrane Technology Subsections. • Instances of MD Applications for Characterization Membrane Materials. [ABSTRACT FROM AUTHOR]

• PAES hemodialysis membrane was selected for blood-membrane interaction study. • Blood- membrane interactions were investigated using spectroscopy analyses. • PAES morphological variation and blood attachments clots were investigated. • Binding energy between human serum proteins and PAES was studied using MDS. Patients with end-stage renal diseases (ESRD) require specific health cares as the accumulation of toxins due to the lack of kidney functionality would affect their lives. However, the mortality rate is still high due to cardiovascular diseases, socks, etc. A majority of patients with chronic kidney disease (CKD) require hemodialysis services. Blood purifying membranes, as the main component of hemodialysis setups, however, still suffer from lack of optimum biocompatibility, which results in morbidity and mortality of hemodialysis service receiving patients. The goal of the present case study is to have an in-depth understanding of the current blood-hemodialysis membrane interactions occurring during hemodialysis sessions using poly (aryl ether sulfone)-poly (vinyl pyrrolidone) (PAES-PVP) membrane. Attenuated total reflectance-Fourier transmission infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and solid-state nuclear magnetic resonance (SSNMR) spectroscopy were used to assess the initial chemical structure of the PAES-PVP membrane along with the variations after with the infections with human blood. Furthermore, scanning electron microscopy (SEM) and Transition electron microscopy (TEM) were used to visualize the structural variation of the membrane, blood aggregations, and blood clots on the membrane surface. Besides, Molecular dynamics (MD) simulation was used to assess the interaction of PAES-PVP with major human blood proteins, in terms of interaction energy, which is a novel contribution to the area. The macromolecules (human serum albumin (HSA), human serum transferrin (TRF), and human fibrinogen (HFG)) were chosen from the plasma protein component. These protein structures were chosen based on their different molecular size. Three advanced spectroscopy techniques and two advanced visualization techniques were used for the assessment of the membranes. Spectroscopy studies revealed amine related peak displacement and intensity shifts as indices for attachment of biological species to the polymeric membrane surfaces. Raman peaks around 370, 798, and 1299 cm−1, which experienced significant shifts that were related to carbon-nitrogen and sulfur-oxygen bonds due to protein adhesion. Visualization techniques illustrated blood protein fouling patterns and extracellular vesicles' presence in the pore structures into membranes. The findings highlight the importance of whole structure biocompatibility improvement, rather than only focusing on surface modifications of hemodialysis membranes. Molecular dynamics simulation assessment showed various interaction behaviors for different proteins suggesting molecular weight and active residues of the protein macromolecules play an important role in interacting with polymeric structure. FB had the highest interaction (4,274,749.07 kcal/mol) and binding (10,370.90 kcal/mol) energy with the PAES-PVP structure. TRF owned the lowest interaction energy with respect to its lower molecular weight and fewer active residue count. Image, graphical abstract Computational and experimental assessment of poly aryl ether sulfone structure for hemodialysis application. [ABSTRACT FROM AUTHOR]