PVP-mediated Zr-melamine-MOF/PVDF membranes for efficient uremic toxin removal and anti-fouling

Conventional hemodialysis membranes suffer from limited toxin adsorption capacity and poor biocompatibility. This study proposes a novel strategy to fabricate high-performance composite membranes by incorporating polyvinylpyrrolidone (PVP)-modified Zr-melamine metal-organic frameworks (MOFs) into a polyvinylidene fluoride (PVDF) matrix. PVP acts as a crucial mediator, mitigating MOF agglomeration via steric hindrance and optimizing the membrane's pore structure for enhanced mass transfer. Comprehensive evaluations revealed that the membrane with an optimal PVP dosage (M3) achieved superior simulated hemodialysis performance, with clearance rates of 94.36% for creatinine and 86.37% for urea, significantly outperforming commercial equivalents. Furthermore, the M3 membrane demonstrated robust antifouling properties (stable water flux > 98 L/(m²·h) after 5 cycles), high bovine serum albumin (BSA) retention (98.01%), and excellent biosafety profiles, including low hemolysis (∼13.35%) and negligible Zr/melamine leaching. This work elucidates the structure-performance relationship of PVP-mediated MOF/polymer composites, offering a promising, biocompatible candidate for advanced uremic toxin clearance and long-term hemodialysis therapy.