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-CSmembranes
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 coatedwith TPP-CS is superior and can be used as potentialmaterial for
hemodialysis membrane.