A5004960124- Advanced Fluorescence Microscopy Techniques
- Photoacoustic and Ultrasonic Imaging
- Nanoplatforms for cancer theranostics
- Spectroscopy Techniques in Biomedical and Chemical Research
- Cell Image Analysis Techniques
- Advanced Electron Microscopy Techniques and Applications
- Optical Imaging and Spectroscopy Techniques
- Photochemistry and Electron Transfer Studies
- Spectroscopy and Quantum Chemical Studies
- Biosensors and Analytical Detection
- Optical Coherence Tomography Applications
- Analytical Chemistry and Sensors
- Quantum Dots Synthesis And Properties
- Luminescence Properties of Advanced Materials
- Advanced Radiotherapy Techniques
- Advanced Biosensing Techniques and Applications
- Thermography and Photoacoustic Techniques
- Photoreceptor and optogenetics research
- Optical properties and cooling technologies in crystalline materials
- Electron Spin Resonance Studies
- Near-Field Optical Microscopy
- Radiation Therapy and Dosimetry
- Lipid Membrane Structure and Behavior
- Orbital Angular Momentum in Optics
- Gold and Silver Nanoparticles Synthesis and Applications
National Center for Tumor Diseases
2022-2025
Helmholtz Zentrum München
2016-2024
Technical University of Munich
2016-2024
German Cancer Research Center
2023-2024
Heidelberg University
2023-2024
University Hospital Carl Gustav Carus
2023-2024
Helmholtz-Zentrum Dresden-Rossendorf
2023-2024
TU Dresden
2023
Institute of Biological and Medical Imaging
2016-2022
Max Planck Institute for Biophysical Chemistry
2006-2017
Given the particular importance of dye photostability for single-molecule and fluorescence fluctuation spectroscopy investigations, refined strategies were explored how to chemically retard photobleaching. These will be useful correlation (FCS), fluorescence-based confocal detection (SMD) related techniques. In particular, effects on addition two main categories antifading compounds, antioxidants (n-propyl gallate, nPG, ascorbic acid, AA) triplet state quenchers (mercaptoethylamine, MEA,...
Short-wave infrared (SWIR) fluorescence could become the new gold standard in optical imaging for biomedical applications due to important advantages such as lack of autofluorescence, weak photon absorption by blood and tissues, reduced scattering coefficient. Therefore, contrary visible NIR regions, tissues translucent SWIR region. Nevertheless, bright biocompatible probes is a key challenge that must be overcome unlock full potential fluorescence. Although rare-earth-based core-shell...
In this work, fluorescence correlation spectroscopy (FCS) was used to investigate the effects of potassium iodide (KI) on electronic-state population kinetics a range organic dyes in visible wavelength range. Apart from heavy atom effect promoting intersystem crossing triplet states all dyes, KI also found enhance triplet-state decay rate by charge-coupled deactivation. This deactivation only for with excitation maximum blue range, not those maxima at wavelengths green or longer....
Reversibly photo-switchable proteins are essential for many super-resolution fluorescence microscopic and optoacoustic imaging methods. However, they have yet to be used as sensors that measure the distribution of specific analytes at nanoscale or in tissues live animals. Here we constructed prototype a Ca2+ sensor based on GCaMP5G can switched with 405/488-nm light describe its molecular mechanisms structural level, including importance interaction core barrel structure fluorescent protein...
The intrinsic autofluorescence of biological tissues interferes with the detection fluorophores administered for fluorescence guidance, an emerging auxiliary technique in oncological surgery. Yet, human brain and its neoplasia is sparsely examined. This study aims to assess on a microscopic level by stimulated Raman histology (SRH) combined two-photon fluorescence.With this experimentally established label-free microscopy unprocessed tissue can be imaged analyzed within minutes process...
Abstract Up to now, all demonstrations of reversible saturable optical fluorescence transitions (RESOLFT) superresolution microscopy living cells have relied on the use reversibly switchable fluorescent proteins (RSFP) emitting in green spectral range. Here we show RESOLFT imaging with rsCherryRev1.4, a new red‐emitting RSFP enabling spatial resolution up four times higher than diffraction barrier. By co‐expressing and red RSFPs demonstrate two‐color both for single (“donut”) beam scanning...
Optoacoustic (photoacoustic) imaging has seen marked advances in detection and data analysis, but there is less progress understanding the photophysics of common optoacoustic contrast agents. This gap blocks development novel agents accurate analysis interpretation multispectral images. To close it, we developed a multimodal laser spectrometer (MLS) to enable simultaneous measurement optoacoustic, absorbance, fluorescence spectra. Herein, employ MLS analyze (methylene blue, rhodamine 800,...
Magneto-plasmonic nanocomposites can possess properties inherent to both individual components (iron oxide and gold nanoparticles) are reported demonstrate high potential in targeted drug delivery therapy. Herein, we report on Fe3O4/Au magneto-plasmonic (MPNC) synthesized with the use of amino acid tryptophan via chemical photochemical reduction Au ions presence nanosized magnetite. The magnetic field (MF) induced aggregation was accompanied by an increase absorption near-infrared (NIR)...
Abstract Nerve damage during surgery is a common and serious complication, often leading to chronic pain, functional impairments, diminished quality of life. However, existing methods for intraoperative nerve identification remain insufficient, especially detecting small or hidden branches. Here we present new application clinically approved fluorescent agent, sodium fluorescein, enhance visualization surgery. Utilizing both clinical customized imaging systems, fluorescein remarkably...
The Bragg peak located at the end of ion beam range is one main advantages therapy compared to X-Ray radiotherapy. However, verifying exact position within patient online a major challenge. goal this work was achieve submillimeter proton verification for pulsed beams an energy up 220 MeV using ionoacoustics clinically relevant dose deposition typically 2 Gy per fraction by i) optimal characteristics ionoacoustic signal generation and ii) improved detection correlating with simulated filter...
Inter- or intramolecular distances of biomolecules can be studied by Förster resonance energy transfer (FRET). For most FRET methods, the observable range is limited to 1–10 nm, and labeling efficiency has controlled carefully obtain accurate distance determinations, especially for intensity-based methods. In this study, we exploit triplet state acceptor fluorophore as a readout using fluorescence correlation spectroscopy transient monitoring. The influence donor leaking into channel...
Reversibly switchable fluorescent proteins (rsFPs) have had a revolutionizing effect on life science imaging due to their contribution sub-diffraction-resolution optical microscopy (nanoscopy). Initial studies showed that use as labels could also be highly beneficial for emerging photo- or optoacoustic imaging. It shown in optoacoustics (i) strongly improves the contrast-to-noise ratio modulation and locked-in detection, (ii) facilitates fluence calibration, affording precise measurements of...
The triplet-state kinetics of several fluorescent dyes used in ultrasensitive fluorescence microscopy are investigated using total internal reflection correlation spectroscopy (TIR-FCS). A theoretical outline the analysis and physical aspects evanescent excitation emission at dielectric interfaces given. From this analysis, rates intersystem crossing triplet decay deduced for fluorescein, ATTO 488, rhodamine 110, 123, 6G aqueous buffer solutions. All show slightly higher interface compared...
Abstract Fluorescence microscopy is rapidly turning into nanoscopy. Among the various nanoscopy methods, STED/RESOLFT super-resolution family has recently been expanded to image even large fields of view within a few seconds. This advance relies on using light patterns featuring substantial arrays intensity minima for discerning features by switching their fluorophores between ‘on’ and ‘off’ states fluorescence. Here we show that splitting with grating recombining it in focal plane objective...
Electrostatic interactions between dielectric surfaces and different fluorophores used in ultrasensitive fluorescence microscopy are investigated using objective-based Total Internal Reflection Fluorescence Correlation Spectroscopy (TIR-FCS). The interfacial dynamics of cationic rhodamine 123 6G, anionic/dianionic fluorescein, zwitterionic 110 neutral ATTO 488 monitored at various ionic strengths physiological pH. As analyzed by means the amplitude time-evolution autocorrelation function,...
Photo- or optoacoustics (OA) imaging is increasingly being used as a non-invasive method that can simultaneously reveal structure and function in deep tissue. However, the most frequent transgenic OA labels are current fluorescent proteins not optimized for imaging. Thus, they lack signal strength, their absorption maxima positioned at short wavelengths, thus giving small penetration depths strong background signals. Here, we apply insights from our recent determination of phycobiliprotein...
Abstract Macrophages are one of the most functionally-diverse cell types with roles in innate immunity, homeostasis and disease making them attractive targets for diagnostics therapy. Photo- or optoacoustics could provide non-invasive, deep tissue imaging high resolution allow to visualize spatiotemporal distribution macrophages vivo. However, present macrophage labels focus on synthetic nanomaterials, frequently limiting their ability combine both host viability functionality strong signal...