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Local detection of hydrogen concentration in metals is of central importance for many areas of hydrogen technology, such as hydrogen storage, detection, catalysis, and hydrogen embrittlement. A novel approach to measure the hydrogen concentration in a model system consisting of cubic palladium nanoparticles (Pd NPs), with a lateral resolution down to 4 nm is demonstrated. By measuring the shift of the Pd bulk plasmon peak with scanning transmission electron microscopy (STEM) combined with energy electron loss spectroscopy (EELS) during in situ hydrogen gas loading and unloading, local detection of the hydrogen concentration is achieved in TEM. With this method, concentration changes inside the NPs at various stages of hydrogenation/dehydrogenation are observed with nanometer resolution. The versatility of in situ TEM allows to link together microstructure, hydrogen concentration, and local strain, opening up a new chapter in hydrogen research., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Gold nanorods were decorated with thermoresponsive copolymers of tailored architecture and constructed from N -isopropyl acrylamide and acrylamide. The copolymers were prepared via reversible addition-fragmentation chain transfer polymerization (RAFT) and immobilized on the gold nanorod surface taking advantage of the aurophilicity of its inherently formed trithiocarbonate groups. The topology as well as the average molecular weight of the copolymers was altered using either a monofunctional or 3-arm star RAFT agent. Two-dimensional arrays of the self-assembled core-shell nanostructures were fabricated by drop-casting showing tunable interparticle spacings. In a simulated blood fluid, the lower critical solution temperature of the nanohybrids could be modified over a significant temperature range around body temperature by adjusting the copolymer composition, the architecture, and/or the size of the polymer. The intrinsic photothermal properties of the gold nanorods were utilized to trigger particle aggregation by irradiation at 808 nm in the optical window of human tissues. In effect, a new nanohybrid system with remotely controllable aggregation via an external NIR-light stimulus for nanomedical applications was developed.

We report the straightforward design of a recyclable palladium-core-silica-shell nanocatalyst showing an excellent balance between sufficient stability and permeability. The overall process - design, catalysis and purification - is characterized by its sustainability and simplicity accompanied by a great recycling potential and ultra high yields in C-C-coupling reactions., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

A systematic review and analysis of the most stable spatial arrangements of n carbon, n oxygen, and 2n hydrogen atoms including vibrational zero-point energy up to n = 5 shows that small-molecule aggregates win, typically followed by thermally unstable molecules, before kinetically stable molecules and finally carbohydrates are found. Near n ≈ 60 a crossover to carbon allotropes and ice as the global minimum structure is expected and the asymptotic limit is most likely graphite and ice. Implications for astrochemical and fermentation processes are discussed. Density functionals like B3LYPD3 are found to describe these energy sequences quite poorly, mostly due to an overestimated stability of carbon in high oxidation states., (Copyright © 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Mid-infrared or Raman spectroscopy together with multivariate data analysis provides a novel approach to clinical laboratory analysis, offering benefits due to its reagent-free nature, the speed of the analysis and the possibility of obtaining a variety of information from one single measurement. We compared mid-infrared and Raman spectra of the sera obtained from 247 blood donors. Partial least squares analysis of the vibrational spectra allowed for the quantification of total protein, cholesterol, high and low density lipoproteins, triglycerides, glucose, urea and uric acid. Glucose (mean concentration: 154 mg/dl) is frequently used as a benchmark for spectroscopic analysis and we achieved a root mean square error of prediction of 14.7 and 17.1 mg/dl for mid-infrared and Raman spectroscopy, respectively. Using the same sample set, comparable sample throughput, and identical mathematical quantification procedures Raman and mid-infrared spectroscopy of serum deliver similar accuracies for the quantification of the analytes under investigation. In our experiments vibrational spectroscopy-based quantification appears to be limited to accuracies in the 0.1 mmol/l range., (2005 Society of Photo-Optical Instrumentation Engineers.)

The mechanism by which macromolecules are selectively translocated through the nuclear pore complex (NPC) is still essentially unresolved. Single molecule methods can provide unique information on topographic properties and kinetic processes of asynchronous supramolecular assemblies with excellent spatial and time resolution. Here, single-molecule far-field fluorescence microscopy was applied to the NPC of permeabilized cells. The nucleoporin Nup358 could be localized at a distance of 70 nm from POM121-GFP along the NPC axis. Binding sites of NTF2, the transport receptor of RanGDP, were observed in cytoplasmic filaments and central framework, but not nucleoplasmic filaments of the NPC. The dwell times of NTF2 and transportin 1 at their NPC binding sites were 5.8 +/- 0.2 and 7.1 +/- 0.2 ms, respectively. Notably, the dwell times of these receptors were reduced upon binding to a specific transport substrate, suggesting that translocation is accelerated for loaded receptor molecules. Together with the known transport rates, our data suggest that nucleocytoplasmic transport occurs via multiple parallel pathways within single NPCs.

The fast and reliable determination of concentrations of blood, plasma or serum constituents is a major requirement in clinical chemistry. We explored Raman spectroscopy as a reagent-free tool for predicting the concentrations of different parameters in serum and serum ultrafiltrate. In an investigation using samples from 247 blood donors (which we believe to be the largest study on Raman spectroscopy of serum so far) the concentrations of glucose, triglycerides, urea, total protein, cholesterol, high density lipoprotein, low density lipoprotein and uric acid were determined with an accuracy within the clinically interesting range. After training a multivariate algorithm for data analysis, using 148 samples, concentrations were predicted blindly for the remaining 99 serum samples based solely on the Raman spectra. Relative errors of prediction around 12% were obtained. Moreover, to the best of our knowledge, differentiation between HDL and LDL cholesterol as well as the quantification of uric acid was for the first time successfully accomplished for serum-based Raman spectroscopy. Finally, we showed that ultrafiltration can efficiently reduce fluorescent light background to improve prediction accuracy such that the relative coefficient of variation was reduced for glucose and urea in ultrafiltrate by more than a factor of 2 when compared to serum.