Investigation of Diffusion Modes in Complex Media Using Multidimensional Single-Particle Tracking. (M/F)

Job Description

Thesis Subject

Over the past few decades, single-molecule detection and super-resolution microscopy have provided unique insights into the nanoscale organization and dynamics of biological systems. These approaches have revolutionized our understanding of complex nanostructures and molecular transport mechanisms in heterogeneous environments.
For several years, our group has developed innovative optical and spectroscopic methods to investigate the nanometric organization of neuronal tissues and the diffusion of molecules involved in brain function. In particular, we have strong expertise in the spectroscopy and near-infrared imaging of carbon nanotubes, enabling the visualization and tracking of complex nanoscale motions within biological tissues.
The diffusion of nano-objects in complex environments plays a central role in many biological and physicochemical processes, especially in confined cellular environments, heterogeneous soft materials, and neuronal tissues. However, understanding the local diffusion mechanisms, interactions, and rotational dynamics of nano-objects remains a major challenge, requiring the development of novel experimental and analytical approaches.
The objective of this PhD project is to develop innovative methodologies combining single-particle tracking microscopy and super-resolution microscopy to study fast diffusion modes of nano-objects in complex media. A major methodological challenge of the project will be to significantly increase acquisition speed in single-particle/molecule tracking experiments.
In particular, the PhD candidate will contribute to the development of original microscopy approaches capable of resolving the rotational diffusion of nano-objects over an extended depth-of-focus. The project will also involve the implementation of advanced line-scan microscopy strategies to improve both temporal and spatial resolution.
The first part of the project will focus on model systems, including complex emulsions and biomimetic heterogeneous environments, allowing controlled investigations of confinement effects and diffusion heterogeneity. Additional experimental models will likely be explored and developed throughout the PhD.
In a second stage, the developed methodologies will be applied to ex vivo biological systems, including brain slices and potentially cellular spheroids, in order to investigate local diffusion properties in biologically relevant complex environments.
The PhD project will include strong components in instrumentation, data analysis, and computational modeling. The candidate will develop scientific programming tools for automated trajectory analysis and quantitative characterization of diffusion regimes. Machine learning approaches may also be integrated into the project.
The successful candidate will join a highly interdisciplinary research environment at the interface of physics, biophysics, advanced microscopy, spectroscopy, and data science, with significant opportunities for instrumental and methodological innovation.

Your Work Environment

This multidisciplinary project will take place at the University of Bordeaux campus within the framework of an ERC Synergy Award, in the laboratory of Laurent Cognet (Laboratoire photonique, numérique, nanosciences, https://www.lp2n.institutoptique.fr/) in tight collaboration with Dr. Laurent Groc (Interdisciplinary Institute for Neuroscience ; https://www.iins.u-bordeaux.fr/) and Dr. Erwan Bézard (Institute of Neurodegenerative Diseases, https://www.imn.u-bordeaux.fr/), The LP2N laboratory is recognized worldwide for its research in the field of optics.

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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