A5046542699- Polymer Surface Interaction Studies
- Proteins in Food Systems
- Advanced X-ray Imaging Techniques
- Atmospheric chemistry and aerosols
- Advanced Electron Microscopy Techniques and Applications
- Copper-based nanomaterials and applications
- Atmospheric aerosols and clouds
- Innovative Microfluidic and Catalytic Techniques Innovation
- Microfluidic and Capillary Electrophoresis Applications
- Gas Sensing Nanomaterials and Sensors
- Air Quality and Health Impacts
- Surfactants and Colloidal Systems
- Advanced Photocatalysis Techniques
- Pickering emulsions and particle stabilization
- Air Quality Monitoring and Forecasting
- ZnO doping and properties
- Electron and X-Ray Spectroscopy Techniques
- Protein Interaction Studies and Fluorescence Analysis
- Nanoparticle-Based Drug Delivery
- Ferroelectric and Negative Capacitance Devices
- Electrostatics and Colloid Interactions
- Biotin and Related Studies
- TiO2 Photocatalysis and Solar Cells
- Calcium Carbonate Crystallization and Inhibition
- Food Allergy and Anaphylaxis Research
Paul Scherrer Institute
2016-2022
Swiss Light Source
2018-2019
Helmholtz-Zentrum Berlin für Materialien und Energie
2010-2016
The University of Sydney
2016
Centro Nacional de Biotecnología
2016
Institute of Molecular Functional Materials
2015
University of Bayreuth
2007-2011
Centre National de la Recherche Scientifique
2010
University of Stuttgart
2008
Vesicular nucleo-cytoplasmic transport is becoming recognized as a general cellular mechanism for translocation of large cargoes across the nuclear envelope. Cargo recruited, enveloped at inner membrane (INM), and delivered by fusion outer membrane. To understand structural underpinning this trafficking, we investigated egress progeny herpesvirus capsids where capsid envelopment mediated two viral proteins, forming complex (NEC). Using multi-modal imaging approach, visualized NEC in situ...
The thermodynamics and the driving forces of adsorption beta-lactoglobulin on spherical polyelectrolyte brushes (SPB) are investigated by isothermal titration calorimetry (ITC). SPB consist a polystyrene core onto which long chains poly(styrene sulfonate) grafted. Adsorption isotherms obtained from measurements ITC. analysis ITC shows clearly that process is solely driven entropy while DeltaH > 0. This finding in accordance with proposed mechanism counterion release: Patches positive charges...
Mechanisms of CaCO3 nucleation from solutions that depend on multistage pathways and the existence species far more complex than simple ions or ion pairs have recently been proposed. Herein, we provide a tightly coupled theoretical experimental study precede initial stages nucleation. Starting molecular simulations, succeed in correctly predicting bulk thermodynamic quantities data, including equilibrium constants, titration curves, detailed x-ray absorption spectra taken supersaturated...
Cryo-soft X-ray tomography (cryo-SXT) is a powerful imaging technique that can extract ultrastructural information from whole, unstained mammalian cells as close to the living state possible. Subcellular organelles including nucleus, Golgi apparatus and mitochondria have been identified by morphology alone, due similarity in contrast transmission electron micrographs. In this study, we used cryo-SXT image endosomes autophagosomes, are particularly susceptible chemical fixation artefacts...
Abstract In viscous, organic-rich aerosol particles containing iron, sunlight may induce anoxic conditions that stabilize reactive oxygen species (ROS) and carbon-centered radicals (CCRs). laboratory experiments, we show mass loss, iron oxidation radical formation release from photoactive organic iron. Our results reveal a range of temperature relative humidity, including ambient conditions, control ROS build up CCR persistence in photochemically active, viscous particles. We find can attain...
Recent advances in nanoparticle design have generated new possibilities for nano-biotechnology and nano-medicine. Here we used cryo-soft X-ray tomography (cryo-SXT) to collect comprehensive three-dimensional (3D) data characterise the interaction of superparamagnetic iron oxide nanoparticles (SPION) with a breast cancer cell line. We incubated MCF-7 (a human line) from 0 24 h SPION (15 nm average diameter, coated dimercaptosuccinic acid), system that has been studied previously using various...
We report a facile and novel method for the fabrication of Cu2O@PNIPAM core-shell nanoreactors using Cu2O nanocubes as core. The PNIPAM shell not only effectively protects from oxidation, but also improves colloidal stability system. microgels can work efficiently photocatalyst decomposition methyl orange under visible light. A significant enhancement in catalytic activity has been observed compared with pure nanocubes. Most importantly, photocatalytic be further tuned by thermosensitive...
The adsorption of bovine hemoglobin (BHb) onto colloidal spherical polyelectrolyte brushes (SPBs) is studied by a combination small-angle X-ray scattering (SAXS) and Fourier transform infrared spectroscopy (FTIR). SPBs consist polystyrene core which long chains poly(styrene sulfonic acid) are grafted. Hemoglobin tetrameric protein that disassembles at low pH's high ionic strengths. embedded into the brush layer composed strong polyacids. Thus, subjected to pH strength largely differs from...
We present the first time-resolved investigation of motions proteins in densely grafted layers spherical polyelectrolyte brushes. Using small-angle x-ray scattering combined with rapid stopped-flow mixing, we followed uptake bovine serum albumin by poly(acrylic acid) layer high spatial and temporal resolution. find that total amount adsorbed protein scales time as ${t}^{1/4}$. This subdiffusive behavior is explained on basis directed motion along chains.
In order to take full advantage of novel functional materials in the next generation sensorial devices scalable processes for their fabrication and utilization are great importance. Also understanding lending properties those is essential. Among most sought-after sensor applications low-cost, highly sensitive selective metal oxide based gas sensors. Yet, surface reactions responsible provoking a change electrical behavior layers insufficiently comprehended. Here, we have used near-edge x-ray...
Microgel-covered interfaces, e.g., in emulsions, have attracted much interest lately. Different imaging techniques been used to image these either flat or curved, investigate their properties and appearance. Techniques such as cryogenic scanning electron microscopy (cryo-SEM) confocal provided valuable insight into microgel-covered systems but still some disadvantages part of the microgels being trapped vitrified liquid need for fluorescent markers. Some can be overcome by using transmission...
Abstract. Iron(III) carboxylate photochemistry plays an important role in aerosol aging, especially the lower troposphere. These complexes can absorb light over a broad wavelength range, inducing reduction of iron(III) and oxidation ligands. In presence O2, ensuing radical chemistry leads to further decarboxylation, production .OH, HO2., peroxides, oxygenated volatile organic compounds, contributing particle mass loss. The peroxides turn reoxidize iron(II) back iron(III), closing...
We present an investigation of β-lactoglobulin adsorption onto spherical polyelectrolyte brushes (SPBs) by small angle X-ray scattering (SAXS). The SPB consists a polystyrene core which long chains poly(styrene sulfonate) are grafted. amount and the distribution proteins adsorbed in brush layer at low ionic strength can be derived from SAXS. analysis SAXS data reveals additionally that some protein molecules form aggregates about six monomers state. Furthermore, position slightly bound...
Correlative fluorescence and soft X-ray cryo-microscopy/tomography on flat sample holders is perfectly suited to study the uncompromised physiological status of adherent cells at its best possible preservation by imaging after fast cryo-immobilization. To understand mechanism which herpesviruses induce nucleoplasmic reticulum, i.e. invaginations nuclear envelope, during their egress from host cell nucleus, morphologically similar structures found in laminopathies chemical induction were...
X-ray photoelectron spectroscopy (XPS) and near-edge absorption fine structure (NEXAFS) support the idea that during nitrogen doping of TiO<sub>2</sub> nanoribbons N<sub>2</sub> molecules may be formed trapped in nanostructures.
The immobilization of bovine serum albumins (BSA) onto cationic spherical polyelectrolyte brushes (SPB) consisting a solid polystyrene (PS) core and densely grafted poly(2-aminoethyl methacrylate hydrochloride) (PAEMH) shell was studied by small-angle X-ray scattering (SAXS). observed dynamics adsorption BSA SPB time-resolved SAXS can be divided into two stages. In the first stage (tens milliseconds), added proteins as in-between bridge instantaneously caused aggregation SPB. Then penetrated...
Mast cells play an important role in allergic responses. During activation, these undergo degranulation, a process by which various kinds of mediators stored the granules are released. Granule homeostasis mast has mainly been studied electron microscopy (EM), where fine structures subcellular organelles partially destroyed during sample preparation. Migration and fusion have not detail three dimensions (3D) unmodified samples. Here, we utilized soft X-ray tomography (SXT) coupled with...
We study the change of size and structure freely suspended single lamella nanoparticles polyethylene during thermal annealing in aqueous solutions. Using small-angle x-ray scattering cryogenic transmission electron microscopy, it is shown that a doubling crystalline sandwiched between two amorphous polymer layers obtained by at 125 C. This thickening can be understood terms an unlooping chains within nanoparticle. In addition variation temperature from 90 C to 115 demonstrates inverse...
Transmission X-ray microscopy is employed to detect nanoscale valence changes in resistive switching SrTiO3 thin film devices. By recording Ti L-edge spectra of samples different states, we could show that some spots with slightly distorted structure and a small reduction Ti3+ are already present the virgin films. In ON-state, these further reduced degrees while remaining persists Ti4+ configuration. These observations consistent self-accelerating within pre-reduced extended growth defects.
Mesenchymal stromal cells (MSCs) are promising candidates in regenerative cell‐therapies. However, optimizing their number and route of delivery remains a critical issue, which can be addressed by monitoring the MSCs’ bio‐distribution vivo using super‐paramagnetic iron‐oxide nanoparticles (SPIONs). In this study, amino‐polyvinyl alcohol coated (A‐PVA) SPIONs introduced for cell‐labeling visualization magnetic resonance imaging (MRI) human MSCs. Size surface charge A‐PVA‐SPIONs differ...
The growth of single-crystal CuO nanowires by thermal annealing copper thin films in air is studied. We show that the density, length, and diameter can be controlled tuning morphology structure deposited DC magnetron sputtering. After identifying optimal conditions for nanowires, chemical bath deposition employed to coat with CdS order form p-n nanojunction arrays. As revealed high-resolution TEM analysis, thickness polycrystalline shell increases when decreasing core a given time...