Physical Chemistry and Chemical Physics of Colloids & (Bio)Interfaces
Environmental Physical Chemistry
The objective of my research is to analyze -through experiments and theory- the molecular to mesoscopic processes that govern the dynamics, fate and transformation of ionic and colloidal contaminants (metals, engineered nanoparticles) in aquatic media and, in particular, their interactions with living microorganisms. Specific attention is paid to the analysis of their intricate reactive transfers to bacterial surfaces and to their physicochemical interactions with the abiotic colloidal components of natural waters. The research contributes to better measuring and rationalizing, at a bio-physico-chemical mechanistic level, the chemical speciation of environmental contaminants in solution, their bioavailability and ecotoxicological impacts on the biota. The followed strategy is based on a multi-technique analysis -from the subnanometric to centimetric scales- of the colloidal and bacterial interfaces that affect contaminants eco-dynamics in aquatic media, which calls for interdisciplinary research allying physical chemistry, physics, chemical physics, microbiology and ecotoxicology. The currently tackled research topics where both experimental and theoretical aspects are combined, include:
Analysis of bioluminescence produced by metal-detecting whole-cell bacterial sensors.
Development of AFM-based strategies for addressing nanoparticle toxicity towards microorganisms.
Dynamics of (di- and tri-valent) metals speciation in colloids and nanoparticles dispersions.
Non-equilibrium transfers of metals to bacteria: bioavailability and metallic complexes lability issues.
Nanoparticle-bacterium interactions addressed at the molecular scale.
Electrokinetics of soft surfaces and (bio)interfaces, e.g. genetically engineered bacteria harboring specific surface phenotypes.
Bipolar electrochemistry in electrokinetics of metallic surfaces.
Bacterial adhesion and biomolecular determinants thereof.