Optical Coherence Microscopy (OCM) towards tomography

• Applicant: Professorin Dr. Tanja Weil
• Subject Area: Biological and Biomimetic Chemistry
• Term: from 2014 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 251255179

Aiming for advanced cell tomography based on interferometric principles is the driving force and the key objective of this fundamental research project. The achieved results so far open the door towards cell tomography, which will be the guideline of this continuation project.Several proof of principle have been achieved in the currently running SNF project 511 955 Molecular Contrast enhanced Optical Coherence Microscopy (MCOCM) (started september 2011 ending august 2013). During this initial part, a novel instrumentation poliOCM and VISOCM have been successfully demonstrated by providing a fast 3D microscopy, with high sensitivity and an extrinsic contrast mechanism based on photothermal mediated light-nanoparticle interaction. The resulting fast in vivo 3D cell imaging opens the door for monitoring cell processes and finally metabolic cell imaging. The shift into the visible wavelength range resulted in highly improved lateral and axial resolution. Using the inherent plasmon resonance of these nanoparticles, their photothermal response promises to assess sub-cellular structures and cell dynamics over longer and relevant time periods i.e. true cell tomography.During the next follow-up phase of this research project, we intend assessing dynamic cell processes with high spatial and temporal resolution microscopy over extended time periods for monitoring cell dynamics at sub- cellular scales. Visualizing neuronal activity and imaging mitochondrial dynamics represent a largely untapped potential becoming accessible due to high resolution and contrast offered by poli-OCM and VIS-OCM. These attempts will be further strengthened by complementary characterization of functionalized nanoparticles (NPs) using Optical Coherence Correlation Spectroscopy (OCCS). They will enable tracking of functional parameters within living cell in all three dimensions, with a high temporal resolution and over long time spans.The present project continues a successful cooperation integrating complementary expertise: the team of Prof. T. Weil, Ulm University, provides a large experience in NPs functionalization, where multifunctional peptide- copolymers linked to nanoparticles enable the targeting of specific proteins and cell structures. The visualization of these labeled structures and proteins through innovative optical instrumentation, developed by the team ofProf. T. Lasser at EPFL, paves the way for the next generation of imaging cell dynamics related to diabetes and Alzheimer research.Overall, this project resides on the broad variety of technologies, tools and skills shared between both research teams. Using all these different and complementary capabilities within the same project will allow the continuation of a broad variety of applications in life science and medicine. Furthermore, the cross-disciplinary character and cooperation of this proposal provides an extremely exciting framework for the PhD candidates and students involved in the project.

• DFG Programme: Research Grants
• International Connection: Switzerland
• Participating Person: Professor Dr. Theo Lasser