X-ray fluorescence (XRF) imaging is a powerful technique for mapping elemental distributions, particularly metals, in biological tissues [1]. However, its broader application is constrained by the scarcity of effective contrast agents. To address this limitation, we developed a novel strategy that uses an approach to trigger site-specific growth of metal nanoparticles (NPs) in situ, enhancing...
Abstract
Recent studies have revealed the presence of diverse bacteria within solid tumors of cancer patients. The intrinsic tumor-targeting properties of these bacteria, along with the selective colonization observed in animal models, have renewed interest in employing bacteria as carriers for cancer therapy. However, due to the limitations of current in vivo imaging technologies, the...
A major characteristic of functional programming languages is that the computation is free of side
effects, meaning that given the same input a function will always produce the same result. If we want
to use side effects like output, computation that may fail or access to โstatesโ of the program, we need
extra tools to simulate these.
In the functional programming language Haskell the...
Dominant missense mutations in eight aminoacyl-tRNA synthetases (aaRSs) are associated with axonal and intermediate forms of Charcot-Marie-Tooth (CMT) disease. The molecular mechanisms by which these ubiquitously expressed enzymes cause selective peripheral neuronal degeneration remain elusive. To address this, we use cell models and patient-derived materials. Employing a variety of...
Nanoparticles (NPs) are being actively developed for applications in disease treatment and diagnosisโfor example, as carriers for mRNA, agents for photothermal therapy in prostate cancer, or as contrast agents for magnetic resonance imaging (MRI)โฏ(1). However, their clinical use remains limited. A major challenge lies in achieving targeted delivery of NPs, as well as in controlling when and...
Formation of biomolecular condensates by liquid-liquid phase separation is a dynamic process that is triggered by variations in environmental conditions such as temperature, pH or ionic strength. Characterising the phase separation behaviour of individual proteins is crucial to understand the mechanism and function of condensate assembly. By using the two paralogs of the eukaryotic Elongation...
Palladium-catalyzed cross-coupling reactions are the most powerful tool in C-C bond formation reactions. Among those, the Suzuki-reaction is of particular interest, as it can be carried out under mild reaction conditions using non-toxic, inexpensive and readily available boronic acids.
The aim was to establish a reaction catalyzed by abundant iron instead of detrimental and expensive...
In the research group "Chemometrics of Complex Material Systems" of Stephan Seifert at the Hamburg School of Food Science, analytical data corresponding to fingerprints of biological samples are analysed. These fingerprints come, for example, from food or written artefacts, and are classified using machine learning methods based on various properties, such as their geographical origin. The...
As part of the Cluster of Excellence โUnderstanding Written Artefactsโ, historical palm leaf manuscripts from South India (Puducherry, Tamil Nadu) are being examined, as they represent one of the worldโs most significant and numerous forms of handwritten artefacts. However, their material properties have hardly been systematically studied, if at all. The aim of this research is to gain...
The low stability of most semiconducting materials is a key challenge in the development of efficient photoelectrochemical (PEC) water splitting cells. Monitoring the semiconductor-electrolyte interface during operation is essential to understand all the underlying photocorrosion processes and, in turn, establishing appropriate mitigation strategies.
We developed a custom-built PEC cell that...
Natural composite materials such as nacre have gained significant interest due to their exceptional mechanical properties, including high hardness and toughness.[1] Promising bio-inspired materials are inorganic nanoplates stabilized by a soft layer of organic ligands. These nanoplates can be self-assembled into hierarchically ordered structures, resembling the architecture of tough...
Towards the stabilization of the FAPbI3 based active layer
T. Stoebke1*, M. T. Duong, N. C. Bigall1,2
1Institute of Physical Chemistry, University Hamburg, Germany
2The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany
*thorben.stoebke@uni-hamburg.de
In recent decades, research activity in the field of nanomaterials and nanoparticles has significantly increased, leading to a...
Atomic layer deposition (ALD) relies on sequential self-limiting gas-solid surface reactions, facilitating conformal coatings with sub-nanometer precision on complex substrates while avoiding shadowing effects. ALD originated in the 1960s and 1970s; however, academic interest significantly rose approximately two decades ago with the commercial availability of the first ALD reactors for...
Plants are exposed to rising CO2 concentrations, which are increasing by 1.5-2.0 ppm annually in the atmosphere. At the same time, more and more plants are experiencing further challenges due to water scarcity. These changing living conditions require most organisms to make corresponding physiological adaptations.
Although science and politics have been tracking the effects of such...
The number of applications which operate in low or even no lighting conditions is increasing rapidly. Examples are smartphone industry, automotive engineering, enhanced vision, and automated material sorting. Indium Arsenide (InAs) Semiconductor Quantum Dots (QDs) are highly promising, RoHS-compliant candidates for infrared (IR) applications, which require much lower manufacturing costs...
The functionality of vascular systems in complex plant regions like nodes, which connect stems with lateral organs, remains only partially understood. Spatially resolved slow-flow measurements could provide new insights into flow dynamics in and between vascular bundles and the conductive connections of lateral organs. Traditional methods lack spatial resolution and imaging flow using contrast...
Understanding proteinโnanoparticle interactions is crucial for evaluating the behaviour of nanoparticles (NPs) in biological environments. While the physicochemical of NPs is determined by factors such as size, shape and surface chemistry, their biological identity is rapidly established upon exposure to biological fluids through the immediate adsorption of biomolecules such as proteins. In...
From the synthesis of nanoparticles and their assembly towards biological applications.
Calcium ions (Caยฒโบ) are critical secondary messengers in T cells, governing activation, gene expression, and effector functions. Precisely manipulating intracellular Caยฒโบ levels is a powerful but challenging approach for studying immunology and developing therapies for immune-related diseases.
We utilised the unique photothermal properties of gold nanostars (AuNSs), which were internalised...
Second-order maximally superintegrable Hamiltonian systems are important structures in mathematical physics. Famous examples are the Kepler-Coulomb system and the Harmonic Oscillator.
We establish a geometric framework for a large class of these systems (joint work with J. Kress and K. Schรถbel). It encodes the superintegrable system in a (1,2)-tensor field.
This geometric data reflects a...
Gels based on semiconductor nanoparticles are of scientific interest for applications in electrochemical sensing or catalysis, because they offer a unique combination of nanoscopic and macroscopic properties.[1,2,3,4] This work focuses on cadmium selenide/cadmium sulfide nanorods and their application as gas sensors.
The particles where synthesized following a synthesis route published by...
Nanoparticles (NPs) have become a hot topic in the development of new, highly sensitive diagnostic methods, especially regarding targeted applications. Shape and size are defined by the properties of the inorganic core and the polymer-shell is of utmost importance for the functionality. This study aims the synthesis and surface functionalisation of Gold Nanoparticles (AuNPs) and Nanoclusters...
The ability to control the morphology of colloidal nanoparticles is fundamental in materials science, as their shape directly determines their physical and chemical properties. Understanding the processes that guide the formation of nanoparticles into a specific shape is crucial for bridging the gap between synthesis and application. Here, we investigate the mechanism governing the formation...
Kinetoplastids are a group of flagellated unicellular eukaryotes, which includes species infectious to mammals such as Trypanosoma cruzi, Trypanosoma brucei and Leishmania spp, the causative agents of Chagas disease, Sleeping sickness and Leishmaniasis, respectively. Current treatments against these parasites are in its majority based on non-specific drugs with aggressive side effects in...
Non-invasive monitoring of marine species is critical for sustainable ecosystem management. This study presents a methodology for the individual identification of Atlantic cod (Gadus morhua) using natural skin pigmentation patterns. The project addresses the limitations of traditional, often invasive, survey methods by developing a computer-vision-based approach for re-identifying individuals...
Engineered tRNAs designed to suppress nonsense mutations (sup-tRNAs) have a great therapeutic potential for a variety of genetic diseases. However, the effects of these tRNAs on the cell translation machinery, especially in the native tRNA pool, are still unknown. Furthermore, it remains unclear whether the sup-tRNA undergoes the same modification processes as the natural tRNAs, and how those...
Aerogels are nanoporous, exceptionally lightweight materials with a large internal surface area, and they maintain the properties of their nanoscopic building blocks at the macroscale. These properties make aerogels attractive for catalytic applications. However, the production of aerogels typically lacks control over the structure at larger length scales. To address this limitation, we...
Water is the largest carrier of energy on the Earth, but negligible amount of this energy has been harnessed. This has prompted researchers to explore the Hydrovoltaic effect, which refers to the generation of electricity from the interaction of water with nanostructured surfaces. Nanoporous materials show promising performance in this regard due to their ability of spontaneous imbibition of...
When designing new materials, one promising strategy is to combine different components to create sensitive or tunable physical and chemical properties. Nanomaterials that exhibit intrinsic functional responses โ such as electrochromic, thermochromic, or photochromic behavior โ play an important role in advancing innovative material technologies, particularly in electrochemical, catalytic, or...
The Molecular Plant Genetics group at the University of Hamburg focuses on understanding the molecular mechanisms that enable plants to exchange information between their tissues and organs and adapt to changing environmental conditions.
A central theme of the group's research is the study of long-distance signalling in plants, particularly the mobile macromolecules that serve as messengers...
Traditional metal oxide (MOX) gas sensors are widely used due to their high sensitivity and low cost of fabrication. However, such resistive sensing elements require high operating temperatures (> 250 ยฐC), are difficult to integrate, and feature only limited chemical selectivity. Addressing these problems, photoactivated resistive MOX sensors, which can be operated at room temperature, are...
Topology is a powerful concept for describing material properties. In magnetism, topological phenomena emerge when spins within a material point in different directions, giving rise to three-dimensional non-coplanar magnetic order. A prominent example is the magnetic skyrmion, a particle-like state in which the spins wrap around the unit sphere. Such non-coplanar spin textures can result from...
Plants have evolved a range of reversible and irreversible, active and passive movements which are often triggered and/or driven by environmental cues such as light, temperature and humidity. Some of these movements rival the accelerations observed in the animal kingdom. Among the fastest plant movements is the explosive dispersal of seeds facilitated by the release of stored elastic energy...
Decoding Campus Vibrations with Distributed Acoustic Sensing.
Cell cultures are a crucial tool in biological science. To accurately mimic complex human tissues, heterogeneous co-cultures consisting of different cell types are essential. However, traditional methods for identifying individual cells in these mixes lack spatial resolution, are destructive, or require thin slicing. Here, we show the use of inorganic nanoparticle tags for X-ray fluorescence...
Nanoparticles are tiny structures with a diameter in the nanometer range that have become increasingly important in recent years due to their unique properties, such as a high surface-to-volume ratio. Semiconductor nanocrystals stand out in this regard because their band gap can be altered due to the quantum size effect, which enables the excitation of charge carriers by visible light. When...
ยฌยฌTransition metal nitrides (TMNs) are emerging as a promising class of materials for application in optoelectronics as well as energy conversion and storage, but they remain rather unexplored, mainly due to a lack of mechanistic understanding of their synthetic pathways. Here we demonstrate a one-pot synthesis, which yields 3 nm phase-pure Cu3PdN nanoparticles after the reaction of Cu...
Accurate classification and analysis of transfer RNAs (tRNAs) using Nanopore sequencing remain challenging due to the high similarity among tRNAs and basecalling errors induced by RNA modifications. We have created a robust workflow for direct tRNA Nanopore sequencing that addresses these challenges through optimized barcoding, demultiplexing, and read mapping strategies. We used barcoding...
Photooxygenations provide a sustainable access to functionalized organic molecules, using visible light as an abundant energy source for small molecule activation and molecular oxygen as a cheap oxidant. A dye operates as an energy mediator, exciting the triplet ground state of molecular oxygen into its singlet excited state which is not merely a highly reactive species but rather a selective...
There is an ongoing need for novel experimental methods that can probe biological macromolecules with high spatiotemporal resolution, as many of the cellular functions associated with such molecules originate not from a static molecular structure, but rather from the structural dynamics over time. However, any such methods must be sufficiently accessible to readily trial on new biological...
Liposome-based SERS Sensor system for double readout of intracellular Iron concentrations and pH changes
AUTHORS: Chengxiu Wei, Robbert Schรผtt, Irene Calderon-Gonzalez, Florian Schulz, Mathias Winterhalter, Ramon Alvarez-Puebla, Wolfgang Parak.
ABSTRACT: Nanoscopic sensor systems based on Fluorescence and SERS microscopy are commonly employed for the detection of biologically...
Modular Reactor for In Situ X-ray Scattering, Spectroscopy, and ATR-IR Studies of Solvothermal Nanoparticle Synthesis
Tjark R. L. Groene,1 Sani Y. Harouna-Mayer,1,2 Melike Gumus Akcaalan,1 Jagadesh Kopula Kesavan,1,2 Lars Klemeyer,1,2 Sarah-Alexandra Hussak,1,3 Lukas Grote,1 Davide Derelli,1...
Optical quantum computing, as well as communication and sensing technology based on quantum correlations are in preparation. These require photodiodes for the detection of about 10^16 photons per second with close to perfect quantum efficiency. Already the radiometric calibration is a challenge. The Heisenberg uncertainty principle combined with the measurement of squeezed light represent a...
Phosphorus (P) limitation and intensifying drought critically constrain forest productivity. Beyond the total amount of P in plants, its allocation (how it is divided among different biochemical fractions) strongly influences how efficiently plants use P and how well they cope with stress. These fractions include inorganic phosphate, nucleic acid P (a key component of DNA and RNA),...
Proteins are dynamic molecular machines, and their ability to function depends not only on their 3-dimensional structure but also on subtle motions, cooperativity, and long-range communication between distant sites. However, capturing these processes at high resolution is often compounded with substantial experimental challenges [1,2]. To address this, we develop and apply advanced...
