Abstract

Single Nano-Object Tracking And Localization Microscopy For Applications In Live Brain Tissues

Laurent Cognet, CNRS Research Director, LP2N - Institut d'Optique, University of Bordeaux

Single molecule microscopy allows nanometer localization of the detected emitters and subtle probing of their spatio temporal nano-environment including in living cells and tissues. I will present several single molecule strategies using different types of nano-emitters to probe complex and confined bio-environments. These include the development of a new probe delivery method in the live animal to perform the first single quantum dot tracking in acute brain slices as well as the development of uPAINT, which constitutes the implementation of PAINT microscopy for achieving super-resolution microscopy in cells including live neurons. Noteworthy, uPAINT also allowed studying functional receptors in interaction while combining super-resolution microscopy and single molecule FRET. For deep tissue imaging, single walled carbon nanotubes, which bear optical resonances in the near infrared and nanoscale dimensions, are promising. Indeed, long trajectories (>10 min) of nanotubes diffusing in the brain extracellular space can be recorded at the single nanotube level. Analysis their movements provides super-resolved maps of tissue structuration which can be modulated upon biochemical digestion of the brain extracellular matrix in live animals.