Development of novel membranes with competitive binding properties for the artificial kidney

Maria Inês Santos

Key information

Authors:

Supervisors:

Maria Clara Henriques Baptista Gonçalves (Maria Clara Henriques Baptista Gonçalves); Mónica Cristina Faria Besteiro (Mónica Cristina Faria Besteiro)

Published in

11/29/2022

Abstract

A competitive binding strategy was used to functionalize monophasic hybrid cellulose acetate/silica (CA/SiO2) membranes with ibuprofen (IBF) to enhance protein-bound uremic toxins (PBUTs) removal. Three monophasic hybrid membranes were synthesized by combining phase inversion and sol-gel techniques: CA22-APT, CA22-APT-IBF(15%), and CA30-TEOS-APT-IBF(3%). Furthermore, it was developed four pure cellulose acetate membranes, CA22, CA30, CA33, and CA35, to evaluate the formamide influence through permeation studies. All the membranes were characterized in the Artificial Kidney (AK) in terms of hydraulic permeability (Lp), permeation to PBUTs as well as \ac{HSA} filtration. The molecular weight cut-off (MWCO) was accessed through the CELFA P-28 ultrafiltration installation. The morphological characterization was performed by Scanning Electron Microscopy (SEM), and the chemical composition was analyzed by Fourier Transform Infrared Spectroscopy in Attenuated Total Reflection mode (ATR-FTIR). Results for the CA30-TEOS-APT-IBF(3%) and CA30 membranes showed a Lp of 97.6 and 68.6 kg/h/m^2/bar, respectively. The MWCO for CA30-TEOS-APT-IBF(3%) showed a decrease in average pore sizes in comparison with the pure CA30 membrane. CA30-TEOS-APT-IBF(3%) and CA30 membranes both permeated IS and rejected 100% of HSA. Overall, the new membranes' performance is promising, and research should be continued to prove, for the first time, the permeation of PBUTs through competitive binding membranes.