6 novembrer 2026 – Hanna MANKO – Single-particle tracking from brain slices to the living brain: challenges and advances

Dr Hanna MANKO- Optics, nanoscience and molecular diffusion physics in living matter lab (Cognet), LP2N – Institut d’Optique d’Aquitaine, Talence (Bordeaux

SPPIN’s seminar series spring-summer 2026, 6 november 2026 11h00, SPPIN common room, 3rd floor, E368

Single-particle tracking from brain slices to the living brain: challenges and advances

Single-particle tracking (SPT) provides a powerful approach to investigate molecular dynamics in biological systems. Extending this technique to the living brain offers the opportunity to study molecular behavior in a complex and physiologically relevant environment, but also introduces significant challenges. In addition to optical limitations associated with thick and heterogeneous tissue, brain motion, tissue deformation, and changes in imaging conditions can complicate particle tracking and the interpretation of the acquired trajectories. Addressing these challenges requires imaging approaches that combine nanoscale sensitivity with reliable tissue visualization and robust image acquisition.

My seminar will explore the challenges of applying SPT to living brain tissue, with particular emphasis on tissue motion and the technical requirements for in-vivo imaging. An automated three-dimensional drift correction strategy based on homogenized differential phase contrast (hDPC) imaging and cross-correlation analysis will be presented. This label-free approach is compatible with both trans- and back-illumination and enables simultaneous tissue visualization and monitoring of sample displacement. The method has been validated in fixed and live organotypic brain slices, where it maintains axial stability within a few tens of nanometers and enables nanoscale reconstruction of extracellular structures from single-particle trajectories. Its applicability to opaque liver tissue in combination with near-infrared SPT further demonstrates its versatility in challenging biological environments.

Finally, the potential of these developments for SPT in the living mouse brain will be discussed, highlighting the remaining technical challenges and the opportunities offered by combining particle tracking with label-free tissue imaging to investigate molecular dynamics in vivo.

Please contact Martin Oheim if you want to make an appointment with Anne Sentenac