Bioelectroanalytical Chemistry

The “bio-electro-analytical chemistry” team explores experimental methodologies that rely on the intimate association of electrochemical and photochemical devices and signals. They are aimed at i) characterizing and quantifying fluxes associated with release events in living cells, passive transport of species across lipid membranes or their efflux during pore formation, ii) diverting electrons generated by photosynthetic organisms, iii) establishing the actual sequence of reactions (or at least delivering a rationale) in catalytic organometallic and photoredox systems. In these research areas, detection sensitivity and temporal resolution are essential. Electrochemical techniques display a particularly high time resolution allowing sub-microsecond events to be monitored. However, biomolecules may be present at concentrations that are too low for the resulting faradaic currents to be detected. Since this limitation is less pronounced in luminescence-based techniques, a common approach in the team for many topics consists in coupling light emission with current collection, an approach that may involve the monitoring of faradaic current and light emission independently (e.g., TIRF imaging), or the control of light emission through the electrochemical activation of redox centers in fluorophores (to discard photoinduced electron transfer), or via electrochemiluminescence upon electrochemical generation of luminescent species. These research directions involve significant methodological developments, including the design of experimental setups adapted to combined photochemical and electrochemical measurements, the constraints associated with working on living organisms (cells, photosynthetic algae), and the study of unique objects (single cells, single vesicles). Consequently, these topics prompt us to develop original models (electron diversion from photosynthesis) as well as setups enabling real-time imaging of fluxes. The required expertise for this approach is well represented in the CBEA team.