Urea-imprinted hollow fiber membranes functionalized with polyeugenol and Di(2-Ethylhexyl) phosphoric acid as hemodialysis membrane candidates

Hemodialysis is an essential treatment for patients with impaired renal function to remove excess metabolic waste from the bloodstream. Although hollow fiber membranes are the most employed membranes in current dialyzer systems, achieving high selectivity toward specific uremic toxins (urea) remains a significant challenge. In this study, urea-imprinted hollow fiber membranes were developed using polyeugenol synthesized through two catalytic pathways, namely BF₃–diethyl ether and H₂SO₄–CH₃COOH. The membranes were further functionalized by incorporating di(2-ethylhexyl) phosphoric acid (D2EHPA) as a carrier to enhance selective transport. Molecularly Imprinted Membranes (MIM) and Non-Imprinted Membranes (NIM) were fabricated via the phase inversion technique using polysulfone as the base polymer and PEGDE as the crosslinker. Characterization by SEM–EDX confirmed the formation of imprinted cavities following urea extraction, while FTIR verified the successful integration of D2EHPA within the membrane matrix. The MIM BF₃ D2EHPA membrane exhibited superior mechanical, hydrophilic, and thermal properties compared with other formulations, indicating a synergistic effect between imprinting and carrier functionality. Transport studies demonstrated higher permeability and selectivity toward urea over creatinine and vitamin B12, with optimal performance observed at pH 7.4. These results demonstrate the potential of MIM BF₃ D2EHPA as an advanced membrane material for hemodialysis applications.