François Ganachaud conference

The Ouzo effect: physical-chemistry behind the process

CNRS researcher, INSA Lyon

Friday, February 21, 2020 – 11:00
Room 120 – Build. 11 E – IPR
Beaulieu campus

The emulsification of any solutes (oil, solid, polymers, lipids…) by solvent shifting, also called the Ouzo effect, is a generic method to prepare, in a very simple and straightforward manner, submicronic droplets, nanocrystals, nanoparticles and liposomes, respectively. It consists in solubilizing the solute of interest in a fully water-miscible solvent (e.g. acetone, THF) and adding a large amount of water, possibly containing a surfactant or dispersant. Even if experimental data show similar trends and features among the different solutes, the physical chemistry of the process is not fully understood. There have been numerous reports these last 5 years that will be summarized in this talk, including some of our (in part unpublished) work. In particular, the emulsification step and the reasons for colloidal metastability of the obtained colloids will be discussed. I will finally focus on encapsulation studies where multiple solutes are coprecipitated at once.

About the speaker

Dr François Ganachaud is a chemist working for the CNRS in the field of polymers and dispersed media, for now 22 years. His interest on spontaneous emulsification was aroused in 2003 by a publication, published in Langmuir by Vitale and Katz, describing the generation of submicronic oil droplets by the so-called Ouzo effect. Since then, several fundamental and applied studies later, this process is almost fully mastered, and for sure applicable to the generation of a variety of colloidal nano-objects. Current studies are devoted to the generation of capsules and fluorescent tracers for biological applications.