Granted Ph.D. Position on Surface Enhanced TIRF Microscopy
Posted by Cyril Favard, on 19 May 2023
Many biological processes, pathological or not, involve cell membranes and their immediate intracellular spatial environment. The study of these processes at the molecular level, directly in the living cell, has been the subject of numerous technical developments, among which fluorescence microscopy has played a predominant role. More recently, so-called “super-resolution” microscopies have benefited greatly from these advances, making it possible to achieve localisation accuracies of the order of 20 nm. Total internal reflection microscopy (TIRF-M), based on evanescent waves created at interfaces, is a widely used platform thanks to its simplicity and the possibility of coupling it to super-resolution techniques. It allows selective excitation of the cell membrane to a depth of about 100 nanometres. However, the TIRF technique, as it is currently marketed, suffers from various limitations that prevent its use in a quantitative and reproducible way. In order to improve its quality, the RCMO team at the Fresnel Institute in Marseille and the MDVA team at the IRIM in Montpellier have developed microscope slides covered with a dielectric thin-film coating that allows the evanescent field to be exalted for a chosen pair (angle of incidence, wavelength) (1,2). During this development, the two teams have accumulated numerical and experimental know-how that now makes it possible to develop these custom slides and optimise them with regard to the instrumental constraints of each microscope. In parallel, these teams are already working on the next generation of this type of slide to make them even more efficient and innovative for biology and health applications. It is in this context that we are proposing a granted Ph.D. thesis for 3 years.
The candidate will initially be responsible for the digital design, manufacture and tests on biological samples of coverslips adapted to the latest generation TIRF system. New developments of slides will then be launched to multiplex, in a simultaneous way, the quantification of biological parameters using these slides. Different applications will be tested including the detection of viruses in a complex environment. We are looking for a candidate with a background in optics, or more generally in experimental physics/instrumentation, who is interested in biology. Experimental knowledge in microscopy and numerical simulation (Matlab, Python) is highly desirable. A strong taste for scientific interdisciplinarity is essential.
The candidate will be positioned in Montpellier in the MDVA team which uses TIRF and super resolution microscopy to follow and understand the assembly of viruses (Sars-Cov2, HIV-1, Influenza) (3,4,5) at the molecular level. The work will be carried out in close collaboration with the RCMO team of the Fresnel Institute in Marseille and the R&D team of the private company. Within the framework of the project, the candidate will also work in the RCMO team on the design and production of the coverslips. The candidate will be supervised by a member of each team. Beyond the scientific development aspects, it is expected that the PhD student will be interested in the possibility of industrializing the concepts by providing, during his/her thesis, pre-production runs (one or two hundred) of certain components that will have been considered and tested as optimal.
To apply, contact Cyril Favard (cyril.favard@irim.cnrs.fr) or Aude Lereu (aude.lereu@fresnel.fr).
1- Mouttou et al., (2022), Opt. Express 30, 15365-15375.
2- Mouttou et al., (2023), Optical Materials X, 17.3- Gourdelier et al., (2022) Sci Rep.12(1):14651.
4- Inamdar et al., (2021) Elife; 10:e67321.
5- Inamdar et al., (2019) Viruses. 16;11(1):72.