Jeudi 17 septembre à 11h00 ; salle des séminaires IRPHE
Abstract: Self-assembled and disordered materials such as gels and glasses are ubiquitous in nature and technologies, possessing unique mechanical properties dictated by their mesoscopic structure.
Recently, we demonstrated that passive, sticky colloids immersed in a bath of swimming Escherichia coli aggregate into unconventional clusters and gels whose morphology is directly dictated by bacterial activity.
By leveraging optogenetic E. coli, whose swimming speed is precisely modulated by light, we demonstrate spatial and temporal control over this active aggregation process. This approach serves as a proof of concept for programming the architecture and mechanical responses of hetero-porous 2D gels using activity as a primary design lever, paving the way for on-demand 3D material fabrication.
By reverting this framework of activity-mediated structures, we further investigate the coupling between active matter and complex, highly confined geometries. By introducing swimming bacteria into a disordered, porous environment ( a liquid foam) we explore how structural confinement alters collective bacterial behaviors and forces microenvironmental adaptation.
Together, these parallel tracks establish a comprehensive toolkit for active matter design: utilizing bacteria both as dynamic architects to engineer tailored colloidal materials, and as adaptive probes to navigate and manipulate complex, confined fluids.
Stéphane Guillet, Postdoctoral Fellow, Institute of Science and Technology Austria (ISTA)