Reference : UMR5031-CORAME0-024
Workplace : PESSAC
Date of publication : Wednesday, June 15, 2022
Scientific Responsible name : Nicolas Martin
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 1 September 2022
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
Living cells are complex chemically reactive compartments that dynamically orchestrate multiple reactions at the same time. Coacervate micro-droplets produced by associative liquid-liquid phase separation between oppositely charged polyelectrolytes are good candidates to model simplified cells. Coacervates selectively sequester (bio)molecular solutes, and can sustain both enzymatic and non-enzymatic chemical reactions. However, control over reactivity in coacervates remains challenging. A promising approach is to dynamically modulate the formation and dissolution of coacervate droplets with external stimuli.
The aim of this PhD is to design light-responsive coacervates produced by self-assembly between azobenzene molecules and oppositely charged polyelectrolytes. We will synthesize a series of charged azobenzene derivatives and will exploit their photo-isomerization properties to form and dissolve coacervate droplets in response to light. The kinetics of coacervate formation/dissolution will be characterized by microfluidics. We will then exploit the reversible formation/dissolution of these coacervates for the spatiotemporal control of biomolecule encapsulation and (bio)chemical reactivity. Our results will open new perspectives for the control over reactions in artificial cells and shed light on the emergence of the first protocells.
 N. Martin, Dynamic synthetic cells based on liquid–liquid phase separation, ChemBioChem, 20, 2553-2568 (2019)
 N. Martin et al. Photoswitchable phase separation and oligonucleotide trafficking in DNA coacervate microdroplets, Angew. Chem. Int. Ed., 58, 14594-14598 (2019)
 T. Fraccia, N.Martin, Non-enzymatic oligonucleotide ligation in photoswitchable coacervate protocells sustains compartment-content coupling, ChemRxiv (2021)
The candidate must hold a Master or Engineer degree in chemistry/physical-chemistry with an interest for interdisciplinary research, should be curious and motivated, and have a sense of teamwork. An interest for soft matter formulation and a first experience in chemical synthesis will be appreciated.
The PhD will take place at Centre de Recherche Paul Pascal près de Bordeaux in the team of N. Martin. CRPP provides cutting-edge facilities for the formulation and characterization of soft matter systems (polymers, surfactants, self-assemblies etc.), chemical synthesis, together with state-of-the-art microfluidic facilities.
Constraints and risks
No specific risk.
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