Permeability improvement of polyethersulfone-polietylene glycol (PEG-PES) flat sheet type membranes by tripolyphosphate-crosslinked chitosan (TPP-CS) coating

In this study, improvement of urea and creatinine permeability of polyethersulfone (PES) membrane by coating with synthesized tripolyphosphate-crosslinked chitosan (TPP-CS) has been conducted. Original and modified membranes, e.g. pristine PES, polyethersulfone-polyethylene glycol (PES-PEG) and PES-PEG/TPP-CS membranes were characterized using FTIR, DTG, SEM, AFM, water uptake, contact angles, porosity measurement, tensile strength test and permeation tests against urea and creatinine. The results show that the PES modification by TPP-CS coating has been successfully carried out. The water uptake ability, hydrophilicity and porosity of the modified membranes increase significantly to a greater degree. All modified membranes have good thermal stability and tensile strength and their permeation ability towards urea and creatinine increase with the increasing concentration of TPP-CS. PES membrane has urea clearance ability of 7.36 mg/dL and creatinine of 0.014 mg/dL; membrane PES-PEG shows urea clearance of 11.87 mg/dL and creatinine of 0.32 mg/dL; while PES-PEG/TPP-CS membrane gives urea clearance of 20.87-36.40 mg/dL and creatinine in the range of 0.52-0.78 mg/dL. These results suggest that the PES-PEG membrane coated with TPP-CS is superior and can be used as potential material for hemodialysis membrane.