Host: Jörg Enderlein (U GOE), MBExC
Local organizer: Alexander Egner (IFNANO)

Speaker: Prof. Guillermo Pedro Acuna, Photonic Nanosystems, Department of Physics, University of Fribourg

Abstract:
Developments in low-cost microscopy have accelerated greatly in recent years due to the technological advances of modern smartphones. Among different features, these devices have image sensors with more pixels, better quantum efficiencies, better optics design for light collection, and larger focal distances in different lenses of multi-camera smartphones. Distinct aspects of smartphones, i.e., portability and compactness, have also pushed forward the development of specific smartphone-based setups useful in Point-Of-Care (POC) applications like clinical diagnostics, quantification of immunoassays, detection of bacteria, cancer cytology, fresh tissue imaging, lead and microplastics quantification. While most of these applications used optical setups designed for fluorescence imaging, only a few of them focused on the detection of single molecule fluorescence.
Here, we developed a portable and inexpensive smartphone-based fluorescence microscope that detects direct emission from single molecules. We tested its performance by analyzing single-molecule intensity traces with three smartphones. We also demonstrated that it can be used for super-resolution microscopy with a Single-Molecule Localization Microscopy (SMLM), DNA-PAINT. The smartphone-based microscope we present is low-cost, portable, easy to use, and can virtually be used with any smartphone, making an impact on a truly broad audience.

Please find here the PDF of the announcement:

Host: Jörg Enderlein (U GOE), MBExC
Local organizer: Alexander Egner (IFNANO)

Speaker: Maciej Wojtkowski, International Center for Translational Eye Research (ICTER) and Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland

Spatio-temporal optical imaging – new method for in vivo imaging

Abstract:
In vivo optical microscopy with quality comparable to fixed samples remains challenging. We developed Spatio-Temporal Optical Coherence (STOC) Imaging, which dynamically adjusts spatial phase relationships in illuminating light to improve imaging quality. Applied to 3-D imaging as Spatio-Temporal Optical Coherence Tomography (STOC-T), this method uses hundreds of uncorrelated spectral interferograms to amplify ballistic photon signals while attenuating scattered photons. STOC-T provides fast, high-contrast imaging, maintaining high resolution at significant depths without repeated measurements. When applied to eye imaging, STOC-T supports functional imaging techniques like Optoretinography (ORG), which measures photoreceptor responses to light stimuli. We introduced Flicker Optoretinography (f-ORG) for measuring rapid optical path length changes under photopic conditions, achieving reproducible, single-nanometer sensitivity in light-adapted eyes. This approach enhances understanding of retinal responses and photopigment photoactivation processes.

Please find here the PDF of the announcement:

Prof. Dr. Walter Nickel from the Heidelberg University Biochemistry Center will held a talk about „Molecular mechanism and machinery driving unconventional secretion of Fibroblast Growth Factor 2 from tumor cells“ during the MBExC Lecture on 7 July, 2025 at 3:00 p.m. at the library of the Humboldtallee 23, room 1.122.

Abstract:
The vast majority of secretory proteins contain N-terminal signal peptides for ER/Golgi-dependent transport into the extracellular space. Exceptions from this general mode of protein secretion from mammalian cells have been discovered more than 30 years ago, yet the molecular mechanisms underlying these alternative secretory pathways have remained elusive until recently. Proteins following such secretory routes have fundamental physiological functions in both health and disease, with Interleukin 1β and Fibroblast Growth Factor 2 being prime examples. The discoveries revealing the molecular mechanisms driving unconventional protein secretion did not only solve long-standing problems in molecular cell biology but also paved the way for new strategies for the treatment of for example inflammatory diseases and cancer.

Host: Prof. Dr. Peter Rehling, University Medical Center Göttingen

Poster of the talk: