A5022149699- Advanced Fluorescence Microscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Quantum Dots Synthesis And Properties
- Photoacoustic and Ultrasonic Imaging
- Optical Imaging and Spectroscopy Techniques
- Analytical Chemistry and Sensors
- Spectroscopy Techniques in Biomedical and Chemical Research
- Electron and X-Ray Spectroscopy Techniques
- Optical Coherence Tomography Applications
- Photosynthetic Processes and Mechanisms
- Chalcogenide Semiconductor Thin Films
- Lipid Membrane Structure and Behavior
- Cell Image Analysis Techniques
- Advanced Biosensing Techniques and Applications
- Photodynamic Therapy Research Studies
- Force Microscopy Techniques and Applications
- Luminescence Properties of Advanced Materials
- Glycosylation and Glycoproteins Research
- Nanocluster Synthesis and Applications
- Advanced Optical Sensing Technologies
- bioluminescence and chemiluminescence research
- X-ray Spectroscopy and Fluorescence Analysis
- Skin Protection and Aging
- Platelet Disorders and Treatments
- Photochemistry and Electron Transfer Studies
Utrecht University
2014-2023
University Medical Center Groningen
2022
University of Amsterdam
2001-2020
Bellingham Technical College
2015
Institute of Molecular Biology and Biophysics
2010
Moog (Netherlands)
2008
Joint Institute for VLBI ERIC
2004
Univé (Netherlands)
2004
University of Bologna
1997
Daresbury Laboratory
1995
A new global analysis algorithm to analyse (hyper-) spectral images is presented. It based on the phasor representation that has been demonstrated be very powerful for of lifetime imaging data. In fluorescence spectrum each pixel in image Fourier transformed. Next, real and imaginary components first harmonic transform are employed as X Y coordinates a scatter (spectral phasor) plot. Importantly, allows rapid (real time) semi-blind unmixing up three image. This slides with fixed cells...
The room-temperature luminescence of single CdSe/ZnS core−shell quantum dots is investigated by spectrally and temporally resolved confocal microscopy. A large (30 nm) blue shift observed in the emission wavelength during illumination air. In nitrogen, no observed. air ascribed to a 1 nm shrinkage CdSe core photooxidation. Photobleaching occurs about 4 times faster than indicating formation nonradiative recombination centers initial light output higher which may be due reduction defect state...
Fluorescent nanoparticles have been synthesized with a metal core, silica-spacer shell, and dye-labeled silica shell. Cascade-yellow-labeled, silver-core carboxyfluorescein-labeled, gold-core dye–metal distances of 24–25 nm exhibit fluorescence enhancement factors as high 12.5 6.8, respectively. particles distance ∼15 show significant quenching.
ABSTRACT Deep microbial biofilms are a major problem in many industrial, environmental, and medical settings. Novel approaches needed to understand the structure metabolism of these biofilms. Two-photon excitation microscopy (TPE) conventional confocal laser scanning (CLSM) were compared quantitatively for ability visualize bacteria within deep vitro pH gradients determined by fluorescence lifetime imaging, together with TPE. A constant-depth film fermentor (CDFF) was inoculated 8 h at 50 ml...
Room temperature time-resolved luminescence measurements on single CdSe/ZnS quantum dots (QDs) are presented. Luminescence spectra were recorded over time periods of up to 30 min with a resolution down 6 ms. A clear 30–40 nm blue shift in the emission wavelength is observed for QDs ambient air, before stops after about 2–3 due photobleaching. The absent nitrogen atmosphere and photobleaching occurs much longer times, 10–15 min. These observations explained by photoinduced oxidation. During...
Summary In this paper a detailed discussion is presented of the factors that affect fluorescence lifetime imaging performance scanning microscope equipped with single photon counting based, two‐ to eight‐channel, time‐gated detection system. particular we discuss sensitivity, resolution, acquisition speed, and shortest lifetimes can be measured. Detection systems four eight time‐gates are significantly more sensitive than two time‐gate Only minor sensitivity differences were found between or...
Semiconductor nanowires of high purity and crystallinity hold promise as building blocks for miniaturized optoelectrical devices. Using scanning-excitation single-wire emission spectroscopy, with either a laser or an electron beam spatially resolved excitation source, we observe standing-wave exciton polaritons in ZnO at room temperature. The Rabi splitting between the polariton branches is more than 100 meV. dispersion curve modes nanowire substantially modified due to light-matter...
Abstract The implementation of a fast fluorescence life‐time imaging method in confocal laser scanning microscope is described. set up utilizes low‐power continuous wave (CW) argon ion equipped with an electro‐optic chopper producing nanosecond pulses repetition rate to 25 MHz. A time‐gated detection technique enables the measurement lifetime pixel 40 μs. first contrast images are presented. Application multilabelling experiments for discrimination between different labels overlapping...
The knowledge of the quantum dot (QD) concentration in a colloidal suspension and quantitative understanding size-dependence band gap QDs are crucial importance from both applied fundamental viewpoints. In this work, we investigate optical properties nearly spherical wurtzite (wz) CuInS2 (CIS) 2.7 to 6.1 nm diameter range (polydispersity ≤10%). synthesized by partial Cu+ for In3+ cation exchange template Cu2- xS nanocrystals, which yields CIS with very small composition variations (In/Cu =...
The suggestion that microdomains may function as signaling platforms arose from the presence of growth factor receptors, such EGFR, in biochemically isolated lipid raft fractions. To investigate role EGFR activation organization rafts we have performed FLIM analyses using putative markers ganglioside GM1 and glycosylphosphatidylinositol (GPI)-anchored GFP (GPI-GFP). was labeled single domain antibodies Llama glama specifically bind without stimulating its kinase activity. Our demonstrate a...
Copper indium sulfide (CIS) quantum dots (QDs) are attractive as labels for biomedical imaging, since they have large absorption coefficients across a broad spectral range, size- and composition-tunable photoluminescence from the visible to near-infrared, low toxicity. However, application of NIR-emitting CIS QDs is still hindered by size shape dispersions yields (PLQYs). In this work, we develop an efficient pathway synthesize highly luminescent wurtzite CIS/ZnS QDs, starting template...
Live-cell correlative light-electron microscopy (live-cell-CLEM) integrates live movies with the corresponding electron (EM) image, but a major challenge is to relate dynamic characteristics of single organelles their 3-dimensional (3D) ultrastructure. Here, we introduce focused ion beam scanning (FIB-SEM) in modular live-cell-CLEM pipeline for organelle CLEM. We transfected cells lysosomal-associated membrane protein 1-green fluorescent (LAMP-1-GFP), analyzed dynamics individual...
Fluorescent proteins have become an invaluable tool in cell biology. The green fluorescent protein variant EGFP is especially widely applied. Use of proteins, including EGFP, however can be hindered by inefficient folding, resulting aggregation and reduced fluorescence. This profound prokaryotic cells. Furthermore, EBFP, a blue rarely used because its dim fluorescence fast photobleaching. Thus, efforts to improve properties such as brightness, photostability are important. Strongly enhanced...
A fast fluorescence lifetime imaging (FLIM) system is developed that can acquire images at a rate of hundreds frames per second. The FLIM based on wide-field microscope equipped with time-gated intensified CCD detector and pulsed laser. acquires the signals from two time gates simultaneously therefore insensitive to movements specimen photo-bleaching. well suited for quantitative biological experiments its performance evaluated in calcium beating neonatal rat myocytes. Several sensitive dyes...
Low-density lipoprotein (LDL) plays a critical role in cholesterol transport and is closely linked to the progression of several diseases. This motivates development methods study LDL behavior from microscopic whole-body level. We have developed an approach efficiently load with range diagnostically active nanocrystals or hydrophobic agents. performed focused experiments on labeled gold (Au-LDL). The labeling procedure had minimal effect size, morphology, composition. Biological function was...
The signal-to-noise ratio of a measurement is determined by the photon economy detection technique and available photons that are emitted sample. We investigate efficiency various frequency-domain lifetime techniques also in relation to time-domain detection. Nonlinear effects discussed introduced use image intensifiers fluorophore saturation. fluorescence imaging microscopy setups connected speed acquisition thus throughput. report on optimal conditions for balancing sensing.