13 octobre 2022

Webinar Jean-François Berret

Dr. Jean-François Berret, Research Director at CNRS is a renowned scientist in soft-condensed matter and biophysics. He is member of the Matière et Systèmes Complexes lab since 2005 and has a strong experience in fundamental and applied research. Dr. Jean-François Berret is an alumnus of the Ecole Normale Supérieure ENS-ULM in Paris with a specialization in physics. He joined the Centre National de la Recherche Scientifique in 1983 at the age of 24, became CNRS research director in 1999 and was promoted to CNRS research director first class in 2011. He worked 4 years in the United States (2000 – 2004) for the Rhodia® company. His current research focuses on the development of soft matter nanotechnology, including new functional structures, devices and systems with stimuli-reactive features at the nano- and microscale. Its objectives are the applications of emerging nanotechnologies in medicine, biology and the environment. Applications include in vivo imaging and therapy tools, microfluidics and microrheology, and the study of living system-machine interfaces.
On the importance of lung fluid rheology for medical applications and toxicology

Abstract: Inhaled nanoparticles (< 100 nm) reaching the deep region of the lungs first interact with the pulmonary surfactant, a thin lipid film lining the alveolar epithelium [1,2]. To date, most biophysical studies have focused on the interfacial properties of the film, and comparatively less work has been done on bulk properties, including structure and rheology [3]. Here we investigate the structural and viscoelastic properties of the biomimetic lung surfactant Curosurf as such, and in the presence of engineered nanoparticles [4]. Curosurf is a medication that is provided to premature infants born before the 7th month of age and suffering from acute respiratory distress syndrome (ARDS). We first show that for medical applications, the rheology of pulmonary surfactant plays a crucial role [5], and that very little information is actually available on this subject. In particular, we explore the possibility of using biomimetic surfactants to treat adults also suffering from ARDS in relation to COVID-19. We then address the issue of surfactant rheology in the presence of model nanoparticles. In the cases of 40 nm-silica and alumina nanoparticles, we show that these interactions induce profound changes in the flow properties of the surfactant, including a transition to a soft-solid behavior [6]. In terms of toxicology, these results suggest that changes in structure and viscosity may interfere with the fluid reorganization and recirculation that occurs during respiration.

1 F. Mousseau, C. Puisney, S. Mornet, R. Le Borgne, A. Vacher, M. Airiau, A. Baeza-Squiban, J.-F. Berret, Nanoscale, 9 (2017) 14967-14978.
2 M. Radiom, M. Sarkis, O. Brookes, E.K. Oikonomou, A. Baeza-Squiban, J.F. Berret, Sci. Rep., 10 (2020).
3 J.-F. Berret, Nat. Commun., 7 (2016) 10134.
4 F. Mousseau, J.-F. Berret, Soft Matter, 14 (2018) 5764-5774.
5 L.-P.-A. Thai, F. Mousseau, E. Oikonomou, J.-F. Berret, Colloids Surf. B, 178 (2019) 337-345.
6 L.-P.-A. Thai, F. Mousseau, E. Oikonomou, M. Radiom, J.-F. Berret, ACS Nano, 14 (2020) 466-475.

13 octobre 2022, 16h3017h30
Webinar (please contact J.-P. Laval or F. Romano for the link)