Dual-layer hollow fibre haemodialysis membrane for effective uremic toxins removal with minimal blood-bacteria contamination

Bacterial endotoxin contamination in dialysate may pass through haemodialysis mem-brane and cause a silent chronic microinflammation to kidney patients. Dual-layer hollow fibre (DLHF) membranes with dual function, biocompatible adsorptive and antibacterial effects were developed to solve the problem of incompatible membrane and endotoxin contamination. All mem-branes were fabricated via the co-extrusion dry-wet phase inversion technique. In this study, silica/ a-mangostin nanoparticle was incorporated into the inner layer of membrane to enhance the bio-compatibility of the membrane while maintaining its adsorption capacity. Activated carbon (AC) was incorporated in the outer layer of membrane for improved antibacterial property. The DLHF membranes were characterised based on its morphology and surface hydrophilicity. The perfor-mance of the DLHF membranes was evaluated in terms of permeability, urea, and creatinine removal capabilities, bovine serum albumin (BSA) rejection and antibacterial properties. The dense and small pore size on the outer layer of AC created a smoother surface for the DLHF membrane. The BSA rejection of the DLHF membranes was enhanced by 6-8% compared to that of unmod-ified single layer hollow fibre membrane. Silica/a-mangostin nanoparticle in the inner layer of mem-brane enhanced the removal of urea and creatinine by chemisorption. Result also showed that the incorporation of AC in the outer layer of DLHF membrane successfully filtered bacteria by bacteria entrapment. DLHF membrane with the combination of silica/a-mangostin nanoparticle in the inner layer and AC in the outer layer possessed the higher bacteria inhibition into blood compartment against Escherichia coli and Staphylococcus aureus, with removal rate of 68% and 75%, respec-tively, and better urea and creatinine removal by 60.57% and 75.18%, respectively, compared to single-layer PSf based membrane. The development of co-adsorptive biocompatible DLHF mem-brane can play an important role in improvement of kidney patient life.(c) 2022 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Automated summary

This study developed dual-layer hollow fiber (DLHF) membranes with dual functions of biocompatible adsorption and antibacterial effects to solve the problem of incompatible membranes and bacterial endotoxin contamination. DLHF membranes with silica/ a-mangostin nanoparticle in the inner layer and activated carbon (AC) in the outer layer showed improved antibacterial properties, urea and creatinine removal capabilities compared to single-layer membranes. The co-adsorptive biocompatible DLHF membrane can play an important role in improving the lives of kidney patients.