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Magnetic nanoparticles offer unique potential for various technological, biomedical, or environmental applications thanks to the size-, shape- and material-dependent tunability of their magnetic properties. To optimize particles for a specific application, it is crucial to interrelate their performance with their structural and magnetic properties. This review presents the advantages of small-angle X-ray and neutron scattering techniques for achieving a detailed multiscale characterization of magnetic nanoparticles and their ensembles in a mesoscopic size range from 1 to a few hundred nanometers with nanometer resolution. Both X-rays and neutrons allow the ensemble-averaged determination of structural properties, such as particle morphology or particle arrangement in multilayers and 3D assemblies. Additionally, the magnetic scattering contributions enable retrieving the internal magnetization profile of the nanoparticles as well as the inter-particle moment correlations caused by interactions within dense assemblies. Most measurements are used to determine the time-averaged ensemble properties, in addition advanced small-angle scattering techniques exist that allow accessing particle and spin dynamics on various timescales. In this review, we focus on conventional small-angle X-ray and neutron scattering (SAXS and SANS), X-ray and neutron reflectometry, gracing-incidence SAXS and SANS, X-ray resonant magnetic scattering, and neutron spin-echo spectroscopy techniques. For each technique, we provide a general overview, present the latest scientific results, and discuss its strengths as well as sample requirements. Finally, we give our perspectives on how future small-angle scattering experiments, especially in combination with micromagnetic simulations, could help to optimize the performance of magnetic nanoparticles for specific applications.
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http://dx.doi.org/10.1039/d1na00482d | DOI Listing |
J Phys Chem Lett
September 2025
Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
Water-ion interactions govern the physicochemical properties of aqueous solutions, impacting the structure of the hydrogen bonding network and ion diffusivities. To elucidate these effects under alkaline conditions relevant to diverse application spaces, we examined NaOD-DO solutions using two-dimensional infrared spectroscopy (2D-IR), small-angle X-ray scattering (SAXS), and nuclear magnetic resonance spectroscopy (NMR). Vibrational energy transfer between the donor anion SeCN, used as a 2D-IR probe, and the acceptor anion OD was used to track the average separation distance of ions in the DO solutions, while SAXS and NMR experiments measured the structure of the bulk DO solvent.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building, Stamford Street, London, SE1 9NH, UK.
As supramolecular assemblies, polypseudorotaxanes (PPR) exhibit inherent advantages in modular adaptability and structural programmability, with the potential to build tuneable platforms integrating various functionalities. Here we report the "one-pot" preparation of a self-assembled thiol-rich PPR (SPPR), where thiolated-α-cyclodextrins (SHαCD) spontaneously thread onto polymers, and are then crosslinked into a three-dimensional network by the thermally-triggered oxidation of thiols into disulfide bonds. The dynamic thiol groups along the SPPR provide remarkable modularity for the functionalization of thiophilic metal nanoparticles (NPs), exemplified by two application vectors.
View Article and Find Full Text PDFBiophys J
September 2025
Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada; Li Ka Shing Institute of Virology, University of Alberta, Edmonton T6G 2E1, Alberta, Canada; Department of Microbiology, Immunology
The dengue virus (DENV) poses a significant threat to human health, accounting for approximately 400 million infections each year. Its genome features a circular structure that facilitates replication through long-range RNA-RNA interactions, utilizing cyclization sequences located in the untranslated regions (UTRs). To gain new insights into the organization of the DENV genome, we purified the 5' and 3' UTRs of DENV in vitro and examined their structural and binding properties using various biophysical techniques combined with computational methods.
View Article and Find Full Text PDFInt J Biol Macromol
September 2025
School of Physics, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece. Electronic address:
Keratins represent an important class of sulfur-rich structural proteins. In this study, the pressure response of α-keratin, extracted from sheep wool, was investigated using Raman spectroscopy up to 4 GPa. A non-polar liquid (a Fluorinert™ FC70/77 mixture) served as the Pressure Transmitting Medium (PTM) in a Diamond Anvil Cell (DAC).
View Article and Find Full Text PDFAppl Radiat Isot
September 2025
Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH), 30 Reactorului Str., PO Box MG-6, Magurele, Ilfov County, RO-077125, Romania. Electronic address:
In this work we study the effect of the matrix of the source on the spectrum and on the full energy peak efficiency for low energy photons. Using realistic simulations carried out with PENELOPE 2018, including detector resolution, we show that small angle Compton scattering does contribute to the peak count rate, implying the dependence of the matrix effects on the linear attenuation coefficient μ and also on the scattering cross section. We show that the effect of Compton scattering can be removed from the apparent peak, resulting a "clean" peak depending only on μ.
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