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Aspirin, hydrochlorothiazide and captopril are drugs widely used for the treatment of cardiovascular diseases which are the main cause of death in the world today. These drugs are generally administered in combination and in consequence it is important to analyze their molecular interactions. By computational calculations based on Functional Theory of Density (DFT), it has calculated global and local indices. These descriptors provide information related to the chemical reactivity of the isolated and combined drugs, that is the object of the present study, in addition to find some system properties as the relationship between the drug-drug binding and their reactivity, and, the relation between the chemical descriptors and the adsorption energy of combined drugs. The findings present new insight for the delivery improvement of combined drugs such as the novel cardiovascular polypills.

Aromatic amines as important intermediates for chemical production have important applications in chemical industry such as plastics, rubber processing, herbicides, dyes, and pharmaceuticals. Catalytic hydrogenation of nitroarenes is the main synthetic method for producing aromatic amines. This work designs and synthesizes a highly efficient and selective catalytic hydrogenation catalyst (Pt-AlOOH/C) using hydrothermal and impregnation methods. The Pt-AlOOH/C catalysts with different loadings (1.0, 0.1, and 0.05 wt%) are successfully obtained by changing the amount of the Pt precursor. The results show that the 1%Pt-AlOOH/C catalyst had the best performance, achieving 97.6% conversion of 4-nitroacetophenone with 96.0% selectivity to p-aminophenone under the following reaction conditions of 0.5 h, 25 °C, and pressure 2.0 MPa. The selectivity of one ─NO₂ hydrogenation for Pt-AlOOH/C also provides excellent catalytic activity and high selectivity to one ─NO₂ being hydrogenated for other nitroarenes (for example, 2-chloronitrobenzene, 2-bromonitrobenzene, p-nitrophenol, 1,3-dinitrobenzene, and p-nitrobenzonitrile) hydrogenation reactions under quite mild reaction conditions. The characterization results show that the Pt nanoparticles with high dispersion are successfully and uniformly loaded on the AlOOH/C support.

The mixed-ligand complexes of Co, Cu, and Cd with 2-aminobenzoxazole (2AB) and Cl (complex 1), 2AB and acetic acid (complex 2), as well as 2AB and iodine (complex 3) have been synthesized, and their X-ray structures are determined. In all three compounds, coordination takes place through the oxazole N atom in a monodentate fashion. The structures of all metal complexes are tetrahedral and displayed by identical formula [M(2AB)₂(Al)₂], where M is Co, Cu, or Cd, while Al is auxiliary ligand Cl, acetic acid, or I. According to Hirshfeld surface analysis, significant molecular interactions are H⋯H ones, while second and third-type main contacts are from X⋯H (X = Halogens) and C⋯H/H⋯C interactions; that is, in all three complexes intermolecular interactions between molecules are mostly hydrophobic. Computational studies of complexes 1, 2, and 3 refined and confirmed the experimental geometric parameters. The electrical properties and charge transfer within the complexes have been explained via frontier molecular orbital (FMO) investigation. Chemically active regions were identified using localized orbital locator (LOL), electron localization function (ELF), and molecular electrostatic potential (MEP). The computed density of states (TDOS) offered insights into the interactions between ligand and metal ions of complexes, while natural bond orbital (NBO) analysis examined charge delocalization.

Electrochemical sensors, as a fast, accurate, and stable type of sensor, process wide applications and promising development prospects in various scenarios such as environmental monitoring, medical diagnosis, and food safety. The generated electrical signals by reactions between electrode materials and targeted analytes enable quantitative or qualitative analysis of the target substances, which always displays more efficient, highly sensitive, and portable compared to the traditional detection methods such as high-performance gas (liquid) chromatography. However, the existence of several core factors (electrode, electrolyte, and signal collection devices) commanded the applicability of electrochemical sensors, practically electrode components. This review summarizes the detection mechanisms and advanced performances of several typical electrode materials and additives used in non-enzyme electrochemical sensors. It also highlights the unique application advantages in detecting nitrite, glucose, heavy metals, and pesticide residues in food safety. The insight provides a sneak peek on suites of electrode materials, including their synthesis process, overall non-enzyme sensor performance, and future perspectives.

It is highly feasible to utilize phase change energy storage technology to construct a phase change material (PCM)-based thermal management system for electronic devices. In this paper, stearic acid (SA) was used as the PCM, and expanded graphite (EG) was chosen as the carrier to prepare SA/EG CPCM. The results showed that EG could prevent the melted SA from leaking, and the combination between SA and EG was only physical. When the mass fraction of EG was 11%, the SA/EG CPCM had good shape stability with a phase change temperature (T_m) of 67.2 °C, a phase change enthalpy (∆H_m) of 204.4 J/g, and a significantly increased in thermal conductivity (6.432 W/(m·K)). In addition, simulation test experiments showed that the peak value of the heating surface was weakened by about 20 °C in the heating stage after loading the CPCM on the electronic device. Therefore, the resultant SA/EG CPCM in this work had great application value.

This study presents donor-π-acceptor type compounds of 3,5-bis(OCH₃)-C₆H₃-C₆H₄-CN (1) and 3,5-bis(OCH₃)-C₆H₃-C₆H₄-CH₂-CN (2), synthesized and characterized through analytical and spectroscopic techniques. Single-crystal X-ray diffraction of compound 2 revealed a triclinic system with a P-1 space group. Despite its centrosymmetric nature, noncovalent interactions, such as CH…π interactions in the crystal packing, prevent antiparallel alignment in bulk, enabling nonlinear optical (NLO) activity. Solvatochromic studies indicated negative solvatochromism with absorption shifts of 72 nm for (1) and 63 nm for (2), attributed to high-ground state dipole moments. The cyano moiety suppresses fluorescence in solution due to twisted confirmation but is enhanced in aggregated states via aggregation-induced emission (AIE) at 90% THF/H₂O for (1) and 70% for (2). Thin film studies with polymethyl methacrylate (PMMA) showed increased emission intensity. Second-order NLO properties, evaluated using the Kurtz–Perry method, revealed compound 2 exhibiting 2.7 times the second harmonic generation (SHG) efficiency of compound 1 due to restricted antiparallel molecular packing. Computational studies of density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at the B3LYP/6–31+G∗∗level of theory confirmed experimental results, validating optical and NLO properties of both compounds. These findings highlight the potential of these compounds for advanced optoelectronic applications.

Hydrothermal synthesis of titanium dioxide nanowires yields high-purity and well-developed grains while exhibiting a low degree of aggregation. TiO2-0.5 and TiO2-0.7 (0.5 ml and 0.7 ml tetrabyl titanate were added to the mixture for TiO2-0.5 and TiO2-0.7) are obtained by varying the content of tetrabutyl titanate through a simple to obtain nanowire particles, followed by annealing at 500 °C in air. The electrochemical properties of the nanoparticles can be improved solely by adjusting the amount of tetrabutyl titanate. Herein, TiO2-0.5 and TiO2-0.7 were synthesized, and their electrochemical performance as negative electrodes for Lithium-ion batteries (LIBs) and supercapacitors was investigated. As a negative electrode for LIBs, the reversible capacity of TiO2-0.7 nanomaterial after 65 cycles at a current density of 100 mA/g is 221.9 mAh/g. In contrast, at current densities of 200 mA/g, 300 mA/g, and 500 mA/g, it is measured as 173.8 mAh/g, 148.4 mAh/g, and 120 mAh/g, respectively. As a supercapacitor electrode material, TiO2-0.7 exhibited a specific capacitance of 121.8 F/g at a current density of 0.2 A/g. These results suggest that this electrode material material has great potential for portable electronic devices in the future due to its ability to modulate the concentration of TiO2 nanowires (TiO2 NWs) by adjusting the content of tetrabutyl titanate.

Chitosan hydrogels are gaining significant importance in the biomedical area field due to their application in wound dressings and drug delivery systems. In the present study, chitosan-based hydrogels were developed and loaded with carvacrol at different concentrations. They were characterized by Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and scanning electron microscopy (SEM). Their biocompatibility was assessed through direct hemolysis tests, yielding favorable results, as they were found to be safe for contact with blood. Another significant finding emerged from the antimicrobial tests, where the hydrogels achieved >95% inhibition against Staphylococcus aureus and >90% against Escherichia coli. Additionally, the hydrogels demonstrated a sustained release of carvacrol over at least 48 h. Those results suggest that chitosan/carvacrol-based hydrogels are promising materials for medical applications, particularly as wound dressings, with biocompatible and antimicrobial properties, as well as for use in drug delivery systems.

p-Nitrophenol (p-NP) is widely used in industrial applications for synthesis of large number of commercially valued products. However, it is dangerous to humans and aquatic life due to its toxicity. In this study, DL-Malic acid, L-Histidine, and L-Cysteine were utilized as sources of carbon, nitrogen, and sulfur respectively to establish a simple, cost-effective, and one-step hydrothermal synthetic process for nitrogen and sulfur-doped carbon dots (N, S-CDs), as a high-performance fluorescent sensor for selective measurement of p-NP based upon Inner filter effect (IFE). The synthesized CDs were subjected to characterization by TEM, FT-IR, XRD, UV–vis, and fluorescence spectroscopy techniques. The developed N, S-CDs exhibited LOD of 0.064 µM and a robust linear response extending from 0.1 to 120 µM. The CDs demonstrated remarkable photostability on exposure to varied environmental factors; including pH, salt, and UV light. The selectivity of sensor was demonstrated by analyzing p-NP response in presence of its analogues and several cations and anions. Results from the analysis of seawater and tap water showed recoveries varying from 98 to 103.8% with RSD of 1.1 to 2%. Moreover, the N, S-CDs offered ease of preparation and operation compared with HPLC, requiring less sophisticated equipment and shorter analysis times.

ChemistrySelect 2024, 9, e202402826.

10.1002/slct.202402826.

The following should be added to the discussion to clarify that further work is needed, before HERV-K potentially can be used as a nano carrier in humans.

Autoantibodies against the HERV-K Gag protein have been detected in several cancer types and rheumatoid arthritis.^[1-4] HERV-K Gag autoantibodies have also been found in a small fraction of healthy individuals.^[1-3] The adaptive immune system may thus recognize HERV-K capsids and clear these from the circulation. This is indeed an important concern that we cannot rule out from our current data.

It is worth noting that the epitope recognized by the HERV-K Gag antibodies has been localized to the far N-terminal in the matrix domain of the Gag protein.^{[2, 3]} Here, we only included the C-terminal capsid domain of the HERV-K Gag protein, which does not appear to be recognized by autoantibodies in at least one study.^[2] However, we cannot conclude that the capsid domain is not recognized by autoantibodies in other cases.

Nevertheless, capsids from the HERV-K Gag protein are easy to form and fill with small molecules, and the capsids, once formed, are robust and stable for a long period. The HERV-K capsids may potentially serve as stable nanocarriers, protecting their cargo from the surrounding environment even if they cannot be used in humans due to the formation of autoantibodies. Finally, HERV-K capsids may also be used as a model system for understanding capsid assembly and cargo loading.