30 Octobre – Thesis defense - Noémie Danné
14 h Amphitheatre - Institut d'Optique d'Aquitaine (Talence)
A study of the nanoscale structure and local viscosity of the brain extracellular space by single carbon nanotubes fluorescence microscopy.
Brain is compound of neurons and glia cells which plays support and protection roles of cellular network. Extra-cellular space (ECS) is the space which exist between cells. Structural modifications could depend on many factors like age, learning or neuro-degenerative diseases. The ECS's volume is equal around 20$%$ of the whole brain volume and the neuro-transmitters and other molecules go through this space to allow optimal neuronal communication. However, the ECS's dimensions and local viscosities still stay poorly-known. ECS is compound inter alia of proteoglycans, glycoaminoglycans (hyaluronic acid...) and cerebrospinal fluid. We proposed in this thesis a strategy to measure the dimensions and rheological properties of acute brain slice extra-cellular space using luminescent carbon nanotubes tracking. For these applications, we studied the biocompatibility and the signal to background ratio of our nanotubes samples to detect them in thick brain slices and be able to measure their diffusion properties.