This study explored the influence of self-assembly on the ultrafiltration (UF) rejection of salvianolic acid B (SaB), a model polyphenolic compound. Employing a combined approach of experimental analysis and molecular dynamics simulations (MDS), we demonstrated pH-dependent self-assembly of SaB at both macroscopic and microscopic levels. At lower pH, larger self-assemblies formed, exhibiting enhanced adsorption onto the membrane surface due to electrostatic attraction. This pH-dependent behavior significantly impacted rejection rates through size exclusion and adsorption mechanisms, leading to a decrease in SaB rejection from 100 % to 31 % as the solution pH increased from 2.4 to 5.6. These findings transcend the specific case of SaB, offering valuable insights into the broader role of self-assembly in UF processes. This knowledge holds potential applications in optimizing separation processes across diverse fields such as food, pharmaceuticals, and environmental science.
Read full abstract