Development of high-speed optical nanoscopy utilizing two-photon fluorescence excitation

Project 10 - Sara Kheireddine

LaVision Biotec GmbH


(1) Integration of confocal two-photon fluorescence microscopy with rescanning SIM and image inversion interferometry

(2) utilize membrane deformable mirror optics to correct for wavefront distortions during deep tissue imaging

(3) multi-color imaging of liver sinusoids in fixed rodent tissue by 2-photon SR-SIM utilizing adaptive optics wavefront corrections

(4) high-speed 2-photon SR-SIM imaging of endothelial tubes, precision cut liver sections, and slices from histological preparations in perfusion chambers

Expected Results:

(1) Two-photon fluorescence microscopy with rescanning SIM and image inversion interferometry demonstrated (resolution 150 nm, speed: 8 frames/s)

(2) imaging of 3D structure of LSECs in planar and 3D cell culture in microfluidic chambers

(3) influence of small molecules (ethanol, paracetamol) and lipoprotein particles on fenestration stability imaged in perfused organ-on-chip models


Project Lead:
Dr. Judith Heidelin

Early Stage Researcher:
Sara Kheireddine

Sara Kheireddine is a 28-year-old Canadian-Lebanese student who joined the DeLIVER ITN network in 2019 as an ESR in LaVision BioTec in Bielefeld, Germany. Born and raised in the United Arab Emirates, Sara then moved to Lebanon in 2008 to pursue her undergraduate studies at the American University of Beirut. After receiving her B.Eng. in Electrical and Computer Engineering, she moved to Germany in 2013 to do an MSc. in Biomedical Engineering at RWTH Aachen University. After finishing her Master thesis in McGill University in Canada, she got accepted into the Ph.D. program in 2016, and is currently a Ph.D. candidate in Bioengineering at McGill. 

Sara’s Ph.D. thesis is primarily concerned with visualizing biological agents in confined spaces, where she works on building and adapting various microscopy and imaging techniques to achieve high spatial resolution with a large field-of-view. At LaVision BioTec GmbH, Sara is working with light sheet fluorescence microscopy (LSFM) and two-photon microscopy to improve spatial resolution through enhanced multiview reconstruction, with the ultimate goal of achieving isotropic resolution. Moreover, structured illumination microscopy (SIM) will eventually be incorporated with two-photon microscopy for high resolution imaging of live samples. The end goal of these improvements is to realize the dynamic visualization of liver sinusoidal endothelial cells (LSECs) with high spatial resolution and a large field-of-view.

In her spare time, Sara enjoys exploring new places, walking in nature, reading books, and watching movies and series.