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In addition to being the core factor in thrombosis, thrombin is involved in various inflammatory disease responses, but few studies have examined whether and how it is involved in membrane-related inflammation. In this study, the thrombin inhibitor dabigatran is used to modify a polyethersulfone dialysis membrane. The modified membrane shows good hydrophilic properties and dialysis performance. It reduces the thrombin level in a targeted manner, thereby significantly inhibiting coagulation factor activation (based on the prothrombin time, international normalized ratio, activated partial thromboplastin time and thrombin time) and reducing the fibrinogen level and platelet adhesion. On thromboelastography, it shows excellent dynamic antithrombotic capacity. The modified membrane inhibited membrane-related inflammation by inhibiting the production of the inflammatory mediators C-reactive protein (CRP), interleukin-6 (IL-6), and interleukin-1β (IL-1β) via the thrombin/complement C5a pathway. Moreover, it is found to be safe in an in vivo study. Thus, the dabigatran-modified polyethersulfone membrane may reduce dialysis-related complications through its dual antithrombotic and anti-inflammatory effects., (© 2023 Wiley-VCH GmbH.)

Conformal organic field-effect transistors (OFETs) have attracted tremendous attention for nextgeneration skin-like electronics due to their mechanical flexibility, low-cost, large-area fabrication, and tunable electrical performance. However, the reported commercial polymer dielectrics suffer from poor solvent resistance, and the limited available antisolvent dielectrics such as hydroxyl-containing PVA and PVP dielectrics OFETs exhibit poor electrical stability. Herein, a nonpolar polysulfone (PSU) dielectric is firstly integrated into solution-processed OFETs and serves as the dielectric layer. Compared with commonly used dielectrics such as PMMA, PS, PVA, and PVP, PSU possesses enhanced solvent stability, thermal stability, humidity stability, and capacitance stability. The solvent resistant PSU dielectric enables the solution-processed C8-BTBT OFET array to achieve on-state currents over 1 mA and ultrahigh mobility up to 10.84 cm² V-1 s -1 (1 Hz). The PSU dielectric OFETs also exhibit excellent cycle stability, thermal stability, humidity stability, and bias stability. Moreover, the conformal OFETs demonstrate ultrahigh mobility (9.34 cm² V-1 s-1), even when adhering to the limited bending radius down to 1 mm, which is the highest mobility among the reported conformal OFETs. Even after crumpling 50 times, there is no significant decrease in electrical performance. Our results provide a novel dielectric selection for stable solution-processed organic transistors, and show the huge potential of PSU dielectrics in future wearable skin-like electronics. [ABSTRACT FROM AUTHOR]

An optimal dialyzer design that provides maximum solute clearance is not available in literature as no analytical theories proposed could include all the factors that are involved in hemodialyzer. All the current dialyzer membranes fail to meet the tradeoff of selectivity and permeability as these hollow fiber membranes still fail in effective toxin clearance and retention of needed solutes. Literatures proposing transport models and optimization factors gain explicit interest now. This paper numerically derives the factors and parameters responsible for effective toxin removal. Thus, the parameters derived will be used in modeling dialyzer membranes by using finite element analysis software and thus the membrane performance will be evaluated. Literatures from standard journals, highlighting experimental data results are then used to benchmark the mathematical model thus proposed. The simulation models in this work put forward optimal designs that can be considered for future works. [ABSTRACT FROM AUTHOR]

In haemodialysis (HD), unwanted substances (uraemic retention solutes or 'uraemic toxins') that accumulate in uraemia are removed from blood by transport across the semipermeable membrane. Like all membrane separation processes, the transport requires driving forces to facilitate the transfer of molecules across the membrane. The magnitude of the transport is quantified by the phenomenon of 'flux', a finite parameter defined as the volume of fluid (or permeate) transferred per unit area of membrane surface per unit time. In HD, as transmembrane pressure is applied to facilitate fluid flow or flux across the membrane to enhance solute removal, flux is defined by the ultrafiltration coefficient (KUF; mL/h/mmHg) reflecting the hydraulic permeability of the membrane. However, in HD, the designation of flux has come to be used in a much broader sense and the term is commonly used interchangeably and erroneously with other measures of membrane separation processes, resulting in considerable confusion. Increased flux is perceived to reflect more 'porous' membranes having 'larger' pores, even though other membrane and therapy attributes determine the magnitude of flux achieved during HD. Adjectival designations of flux (low-, mid-, high-, super-, ultra-) have found indiscriminate usage in the scientific literature to qualify a parameter that influences clinical decision making and prescription of therapy modalities (low-flux or high-flux HD). Over the years the concept and definition of flux has undergone arbitrary and periodic adjustment and redefinition by authors in publications, regulatory bodies (US Food and Drug Administration) and professional association guidelines (European Renal Association, Kidney Disease Outcomes Quality Initiative), with little consensus. Industry has stretched the boundaries of flux to derive marketing advantages, justify increased reimbursement or contrive new classes of therapy modalities when in fact flux is just one of several specifications that determine membrane or dialyser performance. Membranes considered as high-flux previously are today at the lower end of the flux spectrum. Further, additional parameters unrelated to the rate of diffusive or convective transport (flux) are used in conjunction with or in place of KUF to allude to flux: clearance (mL/min, e.g. of β2-microglobulin) or sieving coefficients (dimensionless). Considering that clinical trials in nephrology, designed to make therapy recommendations and guide policy with economic repercussions, are based on the parameter flux they merit clarification—by regulatory authorities and scientists alike—to avoid further misappropriation. [ABSTRACT FROM AUTHOR]

Solution blow spinning (SBS) is used to prepare polysulfone materials (PSf) with different morphologies changing the processing conditions. Morphological study is done by scanning electron microscopy. Materials mainly constituted by beads and fibers are obtained. An optimization strategy based on desirability function approach together with Box–Behnken design is employed to find the best processing conditions to produce PSf materials with tailored morphology. Feed rate and air pressure are the variables of SBS processing conditions with the highest influence on the relative amount of fibers produced while air pressure and a particular balance between work distance and feed rate have the highest impact on the size of fibers. Contact angle measurements are used to understand SBS PSf wettability as a function of morphology. It is demonstrated the possibility of designing PSf materials with particular wettability behavior induced by tailored morphologies obtained from a particular election of SBS processing conditions. [ABSTRACT FROM AUTHOR]

We report the formation of three-dimensionally interconnected nanoporosities with in situ PEGylated pore walls simply by swelling the block copolymers of polysulfone and poly(ethylene glycol) in paired solvents. The produced nanoporous polymers are expected to find important applications in membranes, batteries, chromatography, and haemodialysis. [ABSTRACT FROM AUTHOR]

Tailoring membrane properties for biomedical applications, e.g., hemodialysis, have been a challenge which material scientists have been addressing for last few decades. The fundamental challenge lies in identifying and controlling the parameters which are responsible for yielding cytocompatibility and hemocompatibility to the material. The present article is an attempt to understand the physical parameters which are responsible for the biological manifestations of a polymer membrane. Two types of dialysis membranes, viz., high performance membrane and high cutoff, have been synthesized. Membrane surfaces were modified via dry and wet annealing, and conditions of annealing were optimized. Subsequently, physical and surface properties of the membranes after annealing were investigated. In-depth investigation of biological and blood response has been undertaken on the basis of fundamental parameters like polarizability and surface rigidity. Cell adhesion, proliferation, protein adsorption, hemolysis, platelet adhesion, thrombus formation, and complement activation tests were performed on the membranes. It was observed that dry heating increases surface smoothness but in the process develops cracks on membrane surface as well as increases work of adhesion for blood contact. On the other hand, wet heating of membrane surface not only improves biological performance but it is also easy to retrofit with existing spinning technologies for spinning dialysis membranes. In-house spinning technology was used to synthesize hemodialysis membranes which were annealed at the optimized conditions, and their surfaces were compared with commercial fibers to ascertain the rationale of annealing as a facile method to lend desired surface properties to membranes. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The surfaces of polymeric dialyzer membranes consisting of polysulfone and polyvinylpyrrolidone were investigated regarding the lateral distribution and quantitative surface composition using time-of-flight secondary-ion-mass-spectrometry and x-ray photoelectron spectroscopy. Knowledge of the distribution and composition on the outer surface region is of utmost importance for understanding the biocompatibility of such dialyzer membranes. Both flat membranes and hollow fiber membranes were studied. [ABSTRACT FROM AUTHOR]

The article focuses on the success of cardiovascular implants which depends on the biological reactions occurring at the blood-material interface. The adherence of proteins to the implant surface, thereafter platelets and leukocytes, is mentioned. The dependence of protein adsorption on polymer-based biomaterials on the characteristics of the surface and the fluid shear is cited.