Nanomaterials as electrochemical regulators of bacterial biofilms through the modulation of extracellular electron transport and ion channels.

Bacterial biofilms employ complex electrochemical communication networks, primarily mediated through extracellular electron transfer (EET) and ion channel-dependent signaling, to coordinate metabolic activities and collective behaviors. Recent advances in nanotechnology have unveiled the potential of nanomaterials as novel modulators of these electrochemical networks. This review systematically examines the mechanisms by which nanomaterials modulate electrochemical communication in biofilms, with a particular focus on two principal pathways: (1) redox-driven electron transfer and (2) ion channel-mediated signal transduction. In addition, this article also summarizes the applications of biofilm electrochemistry, from energy harvesting, anti-biofilm therapeutics, agricultural practices, to synthetic biological systems, thereby underscoring the translational potential of nanomaterial-mediated electrochemical regulation. Finally, this review analyzes the key factors influencing these interactions, including the physicochemical properties of nanomaterials (composition, surface charge, size, etc.), the heterogeneity of biofilm architecture (e.g., bacterial species), and environmental variables (pH, temperature, light, etc.). Emerging evidence suggests that nanomaterials can program multispecies biofilm architectures and enable dynamic modulation of microbial communities by manipulating interspecies electrochemical dialogues. Nonetheless, critical challenges remain, such as the identification of key molecular players, the elucidation of dynamic regulatory mechanisms, and the optimization of nanomaterial properties. Future directions highlight the decoding of electrochemical signaling codes, deeper insights into host-microbe electrochemical dialogues, and the use of biofilm "electro-intelligence" to develop next-generation biotechnologies. Overall, this review provides new perspectives for advancing research on electrochemical communication in biofilms and its sustainable applications in health, energy, and the environment.