Missions

Fluorescent molecular rotors (FMRs) derive their mechanochemical sensitivity from
their dynamics in the excited state. During photoexcitation, an FMR undergoes
torsional movements that open non-radiative deactivation pathways. The accessibility
of this relaxation mechanism depends on the intramolecular rotation speed, which is
itself sensitive to the viscosity of the surrounding medium. As a result, the quantum
yield and fluorescence lifetime of an FMR vary directly with local viscosity.
These properties make MRFs suitable probes for providing direct, quantitative
readings and detailed mapping of microviscosity in complex environments. At LOF,
our group has recently developed several applications for these rotors: studying the
mixing of simple fluids in microchannels, developing viscosity-sensitive polymers, and
measuring viscosity within drying droplets.
In this project, the researcher will be tasked with using molecular rotor nanoplatforms
(FMR-NP) to measure and map microviscosity in complex and/or biological fluids,
both in static conditions and under flow.

Activities

As part of a collaborative, interdisciplinary ANR project involving ISM Bordeaux and
MSC Paris Cité, we propose to use FMR-NPs synthesised at ISM to measure and
map the microviscosity of complex fluids, both in static conditions and under flow.
Initially, the FMRs will be tested in model solutions of complex fluids, particularly
polymer solutions, injected into microchannels manufactured at the LOF. The lifetime
of their fluorescence will be measured using a FLIM (Fluorescence Lifetime Imaging
Microscope) available at the LOF.
In a second phase, FMR-NPs from the ISM will be studied in more sophisticated
systems: complex fluids and evolving systems, such as drops under static conditions
or flows in microchannels, again characterised using the FLIM technique.

Skills

We are looking for a dynamic researcher with a PhD in physical chemistry or
chemical engineering.
The ideal candidate will have solid expertise in physical chemistry, a keen interest in
experimentation and modelling, and a genuine enthusiasm for interdisciplinary
projects.
Joining this project is an opportunity to work at the interface of several disciplines,
explore new scientific approaches, and actively contribute to innovative research in
the physical chemistry of complex systems.

Work Context

The 'Laboratory of the Future' (LOF) is a joint research unit of the CNRS, the
University of Bordeaux and Syensqo, a company specialising in the development of
advanced materials and specialty chemicals.
Located in Pessac, within a Syensqo research and innovation centre, the LOF brings
together around twenty researchers from both academia and industry.
As part of this project, active collaboration is planned with the ISM and the MSC.