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Presented here is an effective approach to desmearing slit ultra‐small‐angle neutron scattering (USANS) data, based on complementary small‐angle neutron scattering (SANS) measurements, leading to a seamless merging of these data sets. The study focuses on the methodological aspects of desmearing USANS data, which can then be presented in the conventional manner of SANS, enabling a broader pool of data analysis methods. The key innovation lies in the use of smeared SANS data for extrapolating slit USANS, offering a self‐consistent integrand function for desmearing with Lake's iterative method. The proposed approach is validated through experimental data on porous anodized aluminium oxide membranes, showcasing its applicability and benefits. The findings emphasize the importance of accurate desmearing for merging USANS and SANS data in the crossover q region, which is particularly crucial for complex scattering patterns. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) with reactive oxygen species (ROS)-regulating ability have recently attracted great attention as promising agents for nanomedicine. In the present study, we have analyzed the effects of TiO2 defect structure related to the presence of stoichiometric (Ti4+) and non-stoichiometric (Ti3+ and Ti2+) titanium ions in the crystal lattice and TiO2 NPs aggregation ability on H2O2- and tert-butyl hydroperoxide (tBOOH)-induced ROS production in L929 cells. Synthesized TiO2-A, TiO2-B, and TiO2-C NPs with varying Ti3+(Ti2+) content were characterized by x-ray powder diffraction, transmission electron microscopy, small-angle x-ray scattering, x-ray photoelectron spectroscopy, and optical spectroscopy methods. Given the role of ROS-mediated toxicity for metal oxide NPs, L929 cell viability and changes in the intracellular ROS levels in H2O2- and tBOOH-treated L929 cells incubated with TiO2 NPs have been evaluated. Our research shows that both the amount of non-stoichiometric Ti3+ and Ti2+ ions in the crystal lattice of TiO2 NPs and NPs aggregative behavior affect their catalytic activity, in particular, H2O2 decomposition and, consequently, the efficiency of aggravating H2O2- and tBOOH-induced oxidative damage to L929 cells. TiO2-A NPs reveal the strongest H2O2 decomposition activity aligning with their less pronounced additional effects on H2O2-treated L929 cells due to the highest amount of Ti3+(Ti2+) ions. TiO2-C NPs with smaller amounts of Ti3+ ions and a tendency to aggregate in water solutions show lower antioxidant activity and, consequently, some elevation of the level of ROS in H2O2/tBOOH-treated L929 cells. Our findings suggest that synthesized TiO2 NPs capable of enhancing ROS generation at concentrations non-toxic for normal cells, which should be further investigated to assess their possible application in nanomedicine as ROS-regulating pharmaceutical agents. [ABSTRACT FROM AUTHOR]

Controlling particle dispersity is of huge importance for practical applications in nanoscience and technology. The analysis of small‐angle scattering of X‐rays and neutrons for strongly polydisperse particulate systems is considered from the point of view of describing the type of size distribution function without applying classical regularization approaches. This article presents the development of a method for determining the polydispersity parameters of nanoobjects, based on the analysis of the ratio of various moments of the size distribution function, which are proportional to different invariants of the scattering curve. The use of the unified exponential/power‐law approximation to describe small‐angle scattering data makes it possible to determine the type of distribution, the average size and the spread. The possibilities of the method were tested for several hydrosols of metallic nanoparticles. [ABSTRACT FROM AUTHOR]

Small-angle neutron scattering (SANS) is widely used in structural analysis of complex liquid dispersions. An essential feature of SANS experiments for such systems is hydrogen/deuterium isotopic substitution in liquid media, which makes it possible to change the neutron scattering length density of the solvents, thus providing the basis for the contrast variation technique. In some cases, for dispersed particles with near-spherical symmetry, one can observe in the scattering curves specific points at which the scattered intensity is independent of the scattering contrast between dispersed particles and solvent. These points are referred to as 'isoscattering points' and in monodisperse solutions related to the particle size. Here, we report this effect for rather polydisperse (above 40%) magnetic fluids with core-shell particles in a liquid medium (water). It is shown that the effective isoscattering point can be analyzed to some extent for polydisperse systems, which gives additional possibilities for structural characterization of complex solutions via SANS. [ABSTRACT FROM AUTHOR]

Nanodiamonds combine unique mechanical, thermodynamic and optical properties of diamond with the peculiarities of colloidal dimensions and wide possibilities of chemical modification of their surface. Of particular practical interest is the presence of a branched porous structure inside detonation nanodiamond agglutinates in powders. Application of moderate (up to 1.5 GPa) static pressures allowed us to separate the contributions to small-angle scattering from micro- and nanosized pores. In continuation of the previous studies, the given research shows the possibilities of controlling the fractal structure of the porous system at the nanoscale by applying static pressure. Thus, the partial pore recombination in the pressure range covered leads to the formation of linear pores, in contrast to the branched system characteristic for the initial industrial samples. This modification can have a wide practical impact associated with the loading of anisotropic additives. [ABSTRACT FROM AUTHOR]

Experimental scattering methods together with ab initio calculations were applied for the structural characterization of aggregates in aqueous solutions of fullerene C60 conjugates with amino acid lysine and piperazine. The obtained aggregate size distribution function, as well as fullerene to adduct molar ratio, were explained based on the analysis of intra- and intermolecular interactions. The analysis of the cytotoxic properties of both compounds confirmed their biocompatibility with no toxic effects. [ABSTRACT FROM AUTHOR]

The structure of detonation nanodiamond aqueous dispersions grafted by europium or gadolinium atoms was investigated by small-angle neutron scattering over a wide size scale from 1 to 3000 nm. Similar to the previous studies of nanodiamond suspensions, a strong association of the particle into developed aggregates was revealed. While the characteristic aggregate size depends on the modification of the dispersions and varies in a wide interval of 35–1500 nm, the fractal character of clusters of nanodiamond particles (packed in a specialized branched form with a fractal dimension of 2.4) remains unchanged independent of the cluster size. The effect of the aggregate size increase upon grafting is considered as a basis for the stability reduction mechanism at the microstructural level. [ABSTRACT FROM AUTHOR]

Small-angle X-ray and neutron scattering was applied for the structural characterization of aggregates in water dispersions of fullerene C60 prepared by dialysis method and its conjugate with amino acid arginine. Two compounds are also compared with respect to their toxic properties. Experiments on the cytotoxicity of these systems on the A549, HepG2 and HeLa cells showed no toxic effects of the dispersions. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) with reactive oxygen species (ROS)-regulating ability have recently attracted great attention as promising agents for nanomedicine. In the present study, we have analyzed the effects of TiO 2 defect structure related to the presence of stoichiometric (Ti 4+ ) and non-stoichiometric (Ti 3+ and Ti 2+ ) titanium ions in the crystal lattice and TiO 2 NPs aggregation ability on H 2 O 2 - and tert-butyl hydroperoxide (tBOOH)-induced ROS production in L929 cells. Synthesized TiO 2 -A, TiO 2 -B, and TiO 2 -C NPs with varying Ti 3+ (Ti 2+ ) content were characterized by x-ray powder diffraction, transmission electron microscopy, small-angle x-ray scattering, x-ray photoelectron spectroscopy, and optical spectroscopy methods. Given the role of ROS-mediated toxicity for metal oxide NPs, L929 cell viability and changes in the intracellular ROS levels in H 2 O 2 - and tBOOH-treated L929 cells incubated with TiO 2 NPs have been evaluated. Our research shows that both the amount of non-stoichiometric Ti 3+ and Ti 2+ ions in the crystal lattice of TiO 2 NPs and NPs aggregative behavior affect their catalytic activity, in particular, H 2 O 2 decomposition and, consequently, the efficiency of aggravating H 2 O 2 - and tBOOH-induced oxidative damage to L929 cells. TiO 2 -A NPs reveal the strongest H 2 O 2 decomposition activity aligning with their less pronounced additional effects on H 2 O 2 -treated L929 cells due to the highest amount of Ti 3+ (Ti 2+ ) ions. TiO 2 -C NPs with smaller amounts of Ti 3+ ions and a tendency to aggregate in water solutions show lower antioxidant activity and, consequently, some elevation of the level of ROS in H2O2/tBOOH-treated L929 cells. Our findings suggest that synthesized TiO 2 NPs capable of enhancing ROS generation at concentrations non-toxic for normal cells, which should be further investigated to assess their possible application in nanomedicine as ROS-regulating pharmaceutical agents., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)