Maintaining Antibacterial Activity against Biofouling Using a Quaternary Ammonium Membrane Coupling with Electrorepulsion

Abstract

Antibacterial modification is a chemical-free method to mitigate biofouling, but surface accumulation of bacteria shields antibacterial groups and presents a significant challenge in persistently preventing membrane biofouling. Herein, a great synergistic effect of electrorepulsion and quaternary ammonium (QA) inactivation on maintaining antibacterial activity against biofouling has been investigated using an electrically conductive QA membrane (eQAM), which was fabricated by polymerization of pyrrole with QA compounds. The electrokinetic force between negatively charged Escherichia coli and cathodic eQAM prevented E. coli cells from reaching the membrane surface. More importantly, cathodic eQAM accelerated the detachment of cells from the eQAM surface, particularly for dead cells whose adhesion capacity was impaired by inactivation. The number of dead cells on the eQAM surface was declined by 81.2% while the number of live cells only decreased by 49.9%. Characterization of bacteria accumulation onto the membrane surface using an electrochemical quartz crystal microbalance revealed that the electrorepulsion accounted for the cell detachment rather than inactivation. In addition, QA inactivation mainly contributed to minimizing the cell adhesion capacity. Consequently, the membrane fouling was significantly declined, and the final normalized water flux was promoted higher than 20% with the synergistic effect of electrorepulsion and QA inactivation. This work provides a unique long-lasting strategy to mitigate membrane biofouling.

Rechargeable Multifunctional Anti‐Bacterial AEMs for Electrodialysis: Improving Anti‐Biological Performance via Synergistic Antibacterial Mechanism

“…For the substrate membrane, binding of quaternary ammonium salts to bacteria leads to bacterial death. [ 30 ] In addition, the number of live bacteria was greater than the dead bacteria and the increase in biofilm thickness could be seen in the CLSM 3D images. Consistent with the results presented by fluorescence microscopy (Figure 4 ), this indicates that the original membrane does not possess long‐term antibacterial and anti‐biofilm properties.…”

Antibacterial PVDF Coral-Like Hierarchical Structure Composite Film Fabrication for Self-Cleaning and Radiative Cooling Effect

“…In the past few years, PRC based on a variety of materials and structures have been successfully prepared, which include metamaterials, , multilayer materials, , inorganic photonic structures, ,− and porous structures. − Despite significant progress in developing efficient radiative cooling techniques, it still faces several problems that hinder its practical application, such as contamination by dust and vulnerability to bacterial contamination, especially, after the COVID-19 pandemic, there is a growing concern among the public regarding environmental health in communal spaces. The presence of bacteria associated with dust contamination may facilitate the proliferation of other microorganisms, thereby contributing to biological pollution, − which cannot be overcome solely by relying on the superhydrophobic properties. Nevertheless, few works have considered the bacterial resistance of PRC materials, which are geared toward outdoor applications.…”

Preparation and antibacterial study of waterborne polyurethane modified with lysine and quaternary ammonium salt

“…21 QAS were introduced into the polymer by covalent bonding method, which overcame the shortcomings of easy exudation and loss of antibacterial active ingredients during use, 22 and exhibited synergistic antibacterial properties. 23,24 However, although single-structure antibacterial materials have been widely developed, they still cannot meet the application in the field of high antibacterial. 25,26 Compared to the aforementioned methods, the synergistic system offers more advantages.…”