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Abstract: Thin Cd2Nb2O7 films were grown on single-crystal p-type SiO2/Si substrates by the metallo-organic decomposition (MOD) technique. The films were investigated by X-ray diffraction, X-ray energy-dispersive spectroscopy, and field emission scanning electron microscopy, and showed a single phase (cubic pyrochlore), a crack-free spherical grain structure, and nanoparticles with a mean size of about 68nm. A Cauchy model was also used in order to obtain the thickness and index of refraction of the stack layers (transparent layer/SiO2/Si) by spectroscopic ellipsometry (SE). The dielectric constant (K) of the films was calculated to be about 25 from the capacitance–voltage (C–V) measurements. [Copyright &y& Elsevier]

Emerging contaminants, such as the hormone 17α‐ethynylestradiol (EE), in aquatic environments pose a serious risk to both human and environmental health, making efficient removal essential. This study evaluated the effectiveness of three‐dimensional porous carbon structures derived from poly(acrylic acid) (PAAc, Carbopol 990) as adsorbents for removing EE from aqueous solutions. Activated carbon materials were prepared using varying ratios of KOH as an activating agent (PAAc : KOH; 1 : 0 AAC, 1 : 1 AC1, 1 : 2 AC2, and 1 : 3 AC3). Adsorption tests were conducted by adding 10 mg of the adsorbent to 40 mL of an EE solution (100 ppm, 20 % acetonitrile in water). Analyses including TGA, XRD, and Raman spectroscopy were performed to evaluate the materials’ structural properties and adsorption capacities. Among the materials, AC3 exhibited the highest adsorption capacity for EE (238 mg g−1), followed by AC2 (153 mg g−1) and AC1 (82 mg g−1). The superior efficiency of AC3 can be attributed to its larger surface area and pore volume, enabling greater interaction with EE molecules. These materials demonstrated higher adsorption capacities compared to commercial activated carbons and single‐walled carbon nanotubes. This work opens new possibilities for developing efficient adsorbents, contributing to more effective and sustainable solutions for water purification and environmental protection. [ABSTRACT FROM AUTHOR]

The Zika virus (ZIKV) is a global health threat due to its rapid spread and severe health implications, including congenital abnormalities and neurological complications. Differentiating ZIKV from other arboviruses such as dengue virus (DENV) is crucial for effective diagnosis and treatment. This study presents the development of a biosensor for detecting the ZIKV non-structural protein 1 (NS1) using gold nanoparticles (AuNPs) functionalized with monoclonal antibodies employing dynamic light scattering (DLS). The biosensor named ZINS1-mAb-AuNP exhibited specific binding to the ZIKV NS1 protein, demonstrating high colloidal stability indicated by a hydrodynamic diameter (D H ) of 140 nm, detectable via DLS. In the absence of the protein, the high ionic strength medium caused particle aggregation. This detection method showed good sensitivity and specificity, with a limit of detection (LOD) of 0.96 μg mL -1 , and avoided cross-reactivity with DENV2 NS1 and SARS-CoV-2 spike proteins. The ZINS1-mAb-AuNP biosensor represents a promising tool for the early and accurate detection of ZIKV, facilitating diagnostic and treatment capabilities for arboviral infections., (© 2024 Wiley-VCH GmbH.)

Leishmaniasis, a critical Neglected Tropical Disease caused by Leishmania protozoa, represents a significant global health risk, particularly in resource-limited regions. Conventional treatments are effective but suffer from serious limitations, such as toxicity, prolonged treatment courses, and rising drug resistance. Herein, we highlight the potential of inorganic nanomaterials as an innovative approach to enhance Leishmaniasis therapy, aligning with the One Health concept by considering these treatments' environmental, veterinary, and public health impacts. By leveraging the adjustable properties of these nanomaterials─including size, shape, and surface charge, tailored treatments for various diseases can be developed that are less harmful to the environment and nontarget species. We review recent advances in metal-, oxide-, and carbon-based nanomaterials for combating Leishmaniasis, examining their mechanisms of action and their dual use as standalone treatments or drug delivery systems. Our analysis highlights a promising yet underexplored frontier in employing these materials for more holistic and effective disease management.

A thermally stable carbocationic covalent organic network (CON), named RIO-70 was prepared from pararosaniline hydrochloride, an inexpensive dye, and triformylphloroglucinol in solvothermal conditions. This nanoporous organic material has shown a specific surface area of 990 m 2  g -1 and pore size of 10.3 Å. The material has CO 2 uptake of 2.14 mmol g -1 (0.5 bar), 2.7 mmol g -1 (1 bar), and 6.8 mmol g -1 (20 bar), the latter corresponding to 3 CO 2 molecules adsorbed per pore per sheet. It is shown to be a semiconductor, with electrical conductivity (σ) of 3.17×10 -7  S cm -1 , which increases to 5.26×10 -4  S cm -1 upon exposure to I 2 vapor. DFT calculations using periodic conditions support the findings., (© 2020 Wiley-VCH GmbH.)

Background: A deeper knowledge on the effects of the degradation of magnetic nanoparticles on their magnetic properties is required to develop tools for the identification and quantification of magnetic nanoparticles in biological media by magnetic means., Methods: Citric acid and phosphonoacetic acid-coated magnetic nanoparticles have been degraded in a medium that mimics lysosomal conditions. Magnetic measurements and transmission electron microscopy have been used to follow up the degradation process., Results: Particle size is reduced significantly in 24 h at pH 4.5 and body temperature. These transformations affect the magnetic properties of the compounds. A reduction of the interparticle interactions is observed just 4 h after the beginning of the degradation process. A strong paramagnetic contribution coming from the degradation products appears with time., Conclusions: A model for the in vivo degradation of magnetic nanoparticles has been followed to gain insight on the changes of the magnetic properties of iron oxides during their degradation. The degradation kinetics is affected by the particle coating, in our case being the phosphonoacetic acid-coated particles degraded faster than the citric acid-coated ones.

Two dendrimers were designed and synthesized that contain a 1,3,5-trisubstituted benzenoid core and incorporate 9 and 21 viologen (4,4'-bipyridinium) units in their branches in addition to hydrophilic (aryloxy) terminal groups. For comparison purposes, model compounds containing one and two viologen units were also studied. These polycationic dendrimers form strong host-guest complexes with the dianionic form of the red dye eosin in dilute CH(2)Cl(2) solutions. Titration experiments, based on fluorescence measurements, showed that each viologen unit in the dendritic structures becomes associated with an eosin dianion. Electrochemical (in MeCN) and photosensitization (in CH(2)Cl(2)) experiments revealed that only a fraction of the viologen units present in the dendritic structures can be reduced. This fraction corresponds to the number of viologen units present in the outer shells of the dendrimers. The reasons for incomplete charge pooling are discussed. Comparison with the behavior of polyviologen dendrimers that are terminated with bulky tetraarylmethane groups and were studied previously enabled the role played by the terminal groups in the redox and hosting properties to be elucidated.