Work

Systematic approach to real-time thickness prediction of polyelectrolyte multilayer modified nanoporous membranes using complementary surface-sensitive techniques

Year: 2025

Type: article

Abstract: Nanoporous membranes modified with polyelectrolyte multilayers have emerged as powerful tools for membrane separations, where precise control over multilayer thickness is essential to optimize performance. In this study, we introduce a systematic approach for real-time prediction of multilayer thickness with unparalleled accuracy, utilizing complementary surface-sensitive techniques. By combining quartz crystal microbalance with dissipation monitoring (QCM-D) and surface plasmon resonance (SPR), we demonstrate the ability to design nanoporous membranes with polyelectrolyte multilayers a priori. This approach, which is independent of substrate material and highly reproducible, reveals that for polyelectrolyte systems, the layer density alone suffices to model data obtained from both QCM-D and SPR. Our method proves particularly effective when modified membranes are subjected to pressure conditions, with the synergy of QCM-D and SPR providing a robust solution for multilayer thickness determination. This innovative approach significantly reduces both time and material consumption, offering a streamlined and highly efficient pathway for the systematic design of polyelectrolyte-modified membranes.

Source: Separation and Purification Technology

DOI: 10.1016/j.seppur.2025.133926

Authors: Thomas Schäfer, Leire San José, Kaja Kogal, Carmelo Di Primo