Recently, the causative agents of Maternal Autoantibody-Related (MAR) autism, pathological autoantibodies and their epitopic targets (e.g. lactate dehydrogenase B LDH B peptide), have been ...identified. Herein, we report on the development of Systems for Nanoparticle-based Autoantibody Reception and Entrapment (SNAREs), which we hypothesized could scavenge disease-propagating MAR autoantibodies from the maternal blood. To demonstrate this functionality, we synthesized 15 nm dextran iron oxide nanoparticles surface-modified with citric acid, methoxy PEG(10 kDa) amine, and LDH B peptide (33.8 μg peptide/cm2). In vitro, we demonstrated significantly lower macrophage uptake for SNAREs compared to control NPs. The hallmark result of this study was the efficacy of the SNAREs to remove 90% of LDH B autoantibody from patient-derived serum. Further, in vitro cytotoxicity testing and a maximal tolerated dose study in mice demonstrated the safety of the SNARE formulation. This work establishes the feasibility of SNAREs as the first-ever prophylactic against MAR autism.
Nanoparticle prophylactic against MAR Autism: (A) Autoantigen-coated Dextran Iron Oxide Nanoparticles (DIONPs) formulation are inject intravenously (I.V.). (B) Autoantigen-conjugated DIONPs will ligate MAR auto-Abs in the mother's blood. (C) Clearance of pathological autoantibodies by liver and phagocytes resulting in normal fetal development. Display omitted
The formation energetics and heats of mixing of lead zirconate titanate (PZT) PbZrxTi1−xO3 solid solutions have been investigated using high-temperature oxide melt solution calorimetry. While the ...heat content (H973−H298) is almost constant (80–82 kJ/mol) for x=0.15–1.0, its value for PbTiO3 (x=0.0) is larger (86.15±0.55 kJ/mol). Linear variation in the enthalpy of drop solution, ΔHds, and the enthalpy of formation from the oxides, ΔHf,ox (298 K), is observed in the tetragonal region (0<x<0.5) and continues smoothly into part of the rhombohedral region (0.5<x<0.65). Fitting the data in the tetragonal phase region (0<x<0.5) to a straight line enables an extrapolation to give the heat of the virtual transformation PbTiO3 (tetrag onal→orthorhombic) as 24.0±3.9 kJ/mol. An extrapolation from the rhombohedral region gives 33.3±3.6 kJ/mol for ΔH of the virtual transition PbZrO3 (orthorhombic or rhombohedral→tetragonal). The transition enthalpy between orthorhombic and rhombohedral PbZrO3 is zero within experimental error. The enthalpy of formation from the oxides, ΔHf,ox(298 K), varies from −36.7±2.7 kJ/mol for PbTiO3 to 0.7±4.3 kJ/mol for PbZrO3. The ΔHf,ox(973 K) values agree with previously reported ΔHf,ox values measured in alkali borate solvent at 1073 K. Fitting ΔHmix(973 K) to a regular solution model yields an interaction parameter, W, of 39.8±4.6 kJ/mol. However, structural complexity makes the regular solution model only a crude physical description.
Thin films of amorphous SiNH (a‐SiNH) and amorphous SiNOH (a‐SiNOH) synthesized by plasma‐enhanced chemical vapor deposition (PECVD) are used extensively in the semiconductor industry, but little is ...known regarding their thermodynamic stability, and there are several long‐term reliability issues for these materials. To address the stability issues, a detailed thermodynamic investigation has been conducted on a series of a‐SiNH, and a‐SiNOH dielectric films. High‐temperature oxidative drop‐solution calorimetry in molten sodium molybdate solvent at 1075 K was utilized to determine the formation enthalpies from the elements and from crystalline counterparts/gaseous products. Together with entropy data derived from cryogenic heat capacity measurements, we confirmed that the incorporation of more hydrogen and oxygen leads to more negative enthalpies and Gibbs free energies of formation from elements. Coupled with FTIR structural analysis, the thermochemical data suggest that the Si–H2 chain structure and Si–O–Si bonding configurations provide the system with extra thermodynamic stability. However, the Gibbs free energies of formation from crystalline constituents and gaseous products are either positive or nearly zero, indicating that these amorphous films are not stable against decomposition, which may cause problems in high‐temperature applications.
Carbonate glasses can be formed routinely in the system K2CO3–MgCO3. The enthalpy of formation for one such 0.55K2CO3–0.45MgCO3 glass was determined at 298 K to be 115.00 ± 1.21 kJ/mol by drop ...solution calorimetry in molten sodium molybdate (3Na2O·MoO3) at 975 K. The corresponding heat of formation from oxides at 298 K was −261.12 ± 3.02 kJ/mol. This ternary glass is shown to be slightly metastable with respect to binary crystalline components (K2CO3 and MgCO3) and may be further stabilized by entropy terms arising from cation disorder and carbonate group distortions. This high degree of disorder is confirmed by 13C MAS NMR measurement of the average chemical shift tensor values, which show asymmetry of the carbonate anion to be significantly larger than previously reported values. Molecular dynamics simulations show that the structure of this carbonate glass reflects the strong interaction between the oxygen atoms in distorted carbonate anions and potassium cations.
Metal-organic frameworks are a class of porous compounds with potential applications in molecular sieving, gas sequestration, and catalysis. One family of MOFs, zeolitic imidizolate frameworks ...(ZIFs), is of particular interest for carbon dioxide sequestration. We have previously reported the heat capacity of the sodalite topology of the zinc 2-methylimidazolate framework (ZIF-8), and in this Article we present the first low-temperature heat capacity measurements of ZIF-8 with various amounts of sorbed CO
. Molar heat capacities from 1.8 to 300 K are presented for samples containing up to 0.99 mol of CO
per mol of ZIF-8. Samples with at least 0.56 mol of CO
per mol of ZIF-8 display a large, broad anomaly from 70 to 220 K with a shoulder on the low-temperature side, suggesting sorption-induced structural transitions. We attribute the broad anomaly partially to a gate-opening transition, with the remainder resulting from CO
rearrangement and/or lattice expansion. The measurements also reveal a subtle anomaly from 0 to 70 K in all samples that does not exist in the sorbate-free material, which likely reflects new vibrational modes resulting from sorbate/ZIF-8 interactions. These results provide the first thermodynamic evidence of structural transitions induced by CO
sorption in the ZIF-8 framework.
The modeling of a loss-of-coolant-accident scenario involving nuclear fuels with FeCrAl cladding materials in consideration to replace a Zircaloy requires knowledge of the thermodynamics of oxidized ...structures. At temperatures higher than 1500 °C, oxidation of FeCrAl alloys forms (Fe,Cr,Al)
O
spinels. In situ high-energy X-ray diffraction in a conical nozzle levitator installed at beamline 6-ID-D of the APS was used to study the structural evolution of the oxides as a function of the temperature. Single-phase (spinel) and multiphase (spinel-corundum-FeAlO
) regions are mapped as a function of the temperature for three different compositions of FeCrAl oxidation products. The thermal expansion coefficients and cation distribution in the spinel structure have been refined. The temperature at which complete melting of the fuel cladding is expected has been determined by the liquidus temperatures of the oxidized products to be between 1657 and 1834 °C in a 20% O
/Ar atmosphere using the cooling trace method. The liquidus temperature increases with increasing Al and Cr content in the spinel phase.
A comprehensive understanding of chemical interactions between water and actinide dioxide surfaces is critical for safe operation and storage of nuclear fuels. Despite substantial previous research, ...understanding the nature of these interactions remains incomplete. In this work, we combine accurate calorimetric measurements with first-principles computational studies to characterize surface energies and adsorption enthalpies of water on two fluorite-structured compounds, ThO2 and CeO2, that are relevant for understanding the behavior of water on actinide oxide surfaces more generally. We determine coverage-dependent adsorption enthalpies and demonstrate a mixed molecular and dissociative structure for the first hydration layer. The results show a correlation between the magnitude of the anhydrous surface energy and the water adsorption enthalpy. Further, they suggest a structural model featuring one adsorbed water molecule per one surface cation on the most stable facet that is expected to be a common structural signature of water adsorbed on actinide dioxide compounds.
The structure of lanthanide-doped uranium dioxide, LnxU1-xO2-0.5x+y (Ln = La, Nd), was investigated at pressures up to ∼50–55 GPa. Samples were synthesized with different lanthanides at different ...concentrations (x ∼ 0.2 and 0.5), and all were slightly hyperstoichiometric (y ∼ 0.25–0.4). In situ high-pressure synchrotron X-ray diffraction was used to investigate their high-pressure phase behavior and determine their bulk moduli. All samples underwent a fluorite-to-cotunnite phase transformation with increasing pressure. The pressure of the phase transformation increased with increasing hyperstoichiometry, which is consistent with results from previous computational simulations. Bulk moduli are inversely proportional to both the ionic radius of the lanthanide and its concentration, as quantified using a weighted cationic radius ratio. This trend was found to be consistent with the behavior of other elastic properties measured for Ln-doped UO2, such as Young's modulus.
•Ln-doped UO2 transforms from fluorite to cotunnite at high pressure.•Transition pressure increases with increasing hyperstoichiometry.•Bulk modulus decreases with increasing Ln-dopant radius and concentration.
Water adsorption on the surface of LiCoO2 nanoparticles was investigated. As the water coverage increases the adsorption enthalpy decreases reaching the enthalpy of water condensation (−44 kJ mol−1). ...The experimentally observed average surface energy corresponding to all facets agree well with those reported from DFT calculations. The observed low surface energy is attributed to the surface Co3+ spin transition in nanophase LiCoO2.
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