Journal of Nanoparticle Research最新文献

This study examines the impact of doping Tb³⁺ ions into Ca₁₂Al₁₄O₃₃ to analyze its structural and luminescent properties for potential use in plasma display panels (PDPs). Phosphors were synthesized via the sol–gel method and characterized using XRD, FT-IR, SEM, and PL techniques. Morphological observations via SEM revealed micron-sized, irregularly shaped particles, outlining the distinct morphology of the material. Luminescence investigations revealed an improved energy transfer process apparent in the emission and excitation spectra. Under ultraviolet (UV) and vacuum ultraviolet (VUV) excitation, the predominant green emission at 543 nm, attributed to the ⁵D₄ → ⁷F₅ transition of Tb³⁺ ions, exhibited optimal luminescent properties up to a Tb³⁺ concentration of 0.07 mol. However, the subsequent decrease in emission intensity beyond this threshold occurred due to a concentration-quenching effect. Further analyses demonstrated vacuum photoluminescence at 147 nm and 172 nm, exhibiting robust green emissions at 543 nm associated with the ⁵D₃, ⁵D₄ → ⁷F_J transitions inherent to Tb³⁺ ions. Moreover, all samples exhibited color purity ranging from 85 to 95%. The exceptional luminescence attributes of Ca₁₂Al₁₄O₃₃:Tb³⁺ signify its potential in diverse applications. Notably, its promising applicability in PDP stems is due to its specific emission peaks and luminescent behavior. This study presents avenues for future research, emphasizing potential optimization strategies for PDP applications and exploring the properties of phosphors across various technological domains.

Phenolic compounds impact human health and the environment in both beneficial and undesirable manners. While some phenols are known to be antioxidants, others function as hormones or neurotransmitters, some are significant environmental contaminants, and others have the potential to cause cancer or disturb the endocrine system. To track the amount of toxicity, it is essential to identify and measure these phenols in food, the environment, and human samples. A novel phenol sensing amperometric enzymatic biosensor with a gold electrode was fabricated based on covalent immobilisation of synthesised laccase nanoparticles (LacNPs). The process of synthesising laccase nanoparticles was examined using UV–visible spectrophotometry, FTIR, transmission electron microscopy, zeta potential, and dynamic light scattering techniques. For analysis of electrode fabrication (LacNPs-AuE), scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectra including Nyquist plots and Bode’s plot were examined. Optimisation and evaluation of fabricated biosensor were investigated using cyclic voltammetry studies. The LacNPs-AuE biosensor’s overall characteristics were enhanced by the direct immobilisation of laccase nanoparticles, enabling the analysis at a lower detection limit (0.3 μM), wider linear range (0.1–100 μM and 100 to 600 μM), faster response time (3 s), and high recovery (92–98%). Tea, alcohol, and pharmaceutical samples were tested for total phenolic content using the biosensor; the results were compared with spectrophotometric data.

FeS@Fuller’s Earth (FeS@FE) was synthesized by borohydride reduction in presence of dithionite with a 10% w/w iron loading. FESEM analysis reveal immobilized FeS NPs (40–100 nm) on the surface of Fuller’s Earth with agglomeration. The presence of sulfur as confirmed from XPS and EDX analysis of FeS@FE. Batch adsorption study of FeS@FE for crystal violet (CV) dye adsorption in aqueous solution yielded an optimized adsorption at pH 8, adsorbent dose 0.1 g/L, with a removal of upto 80% of the dye from a 20 mg/L CV solution. The CV adsorption on FeS@FE followed a good non-linear fit for Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich isotherm with R² > 0.95. The maximum monolayer adsorption capacity of FeS@FE was found to be 601.2 mg/g for CV with a D-R Isotherm Free energy of 141.58 kJ/mol at optimum conditions of pH 8, 100 mg/L of CV, and 0.1 g/L of adsorbent dose. The non-linear kinetic fit for CV dye adsorption on FeS@FE fitted to the pseudo-second-order (PSO) and intraparticle diffusion (IPD) models, indicating a strong chemical interaction between CV and FeS@FE. The strong adsorption of CV using FeS@FE is attributed to the Fe-OOH surface formation by FeS immobilized on FE under alkaline conditions, leading to deprotonation and electrostatic adsorption of the dye.

Herein we have developed a heterogeneous catalyst for synthesizing various anticancer and antidiabetic polyhydroquinoline derivatives via heterocyclic synthesis under solvent-free conditions at mild temperatures. This approach eliminates the need for complex cleanup or column chromatography, thus minimizing waste production. Moreover, the catalyst can be recovered and reused up to multiple times without compromising product yields, demonstrating its sustainability and environmental friendliness. Additionally, we evaluated each synthetic derivative for anticancer and antidiabetic activities. Initial assays revealed that certain derivatives exhibit promising inhibition against human breast cancer cells, suggesting their potential as lead structures for future anticancer agents. Furthermore, the synthesized derivatives were assessed for antidiabetic activity, showing superior efficacy. Notably, derivatives containing –H, –CH₃, and –OCH₃ substituents demonstrated excellent anticancer activity, while derivatives containing –H and –Br substituents showed notable antidiabetic activities, highlighting their therapeutic potential. Thus, our study presents an effective and sustainable approach for synthesizing polyhydroquinoline derivatives, emphasizing the catalyst's dual benefits in organic synthesis and medicinal chemistry applications.

This paper offers a thorough examination of cutting-edge membrane technologies used in water treatment, specifically highlighting the use of nanomaterials and nanoparticles in the production of membranes. The text examines advanced purification techniques, including nanofiltration, electro-dialysis, and photocatalysis. The study emphasizes the utilization of state-of-the-art nanomaterials such as carbon nanotubes, graphene oxide, titanium dioxide, and silver nanoparticles, as advanced substances that can adsorb and catalyze effectively. The article discusses the latest advancements in membrane technology, specifically focusing on improvements in processes like as reverse osmosis, ultrafiltration, and microfiltration. An assessment is conducted to determine the efficacy of these nanotechnologies in eliminating diverse organic and inorganic contaminants that provide considerable difficulties for conventional water treatment procedures. Furthermore, this study investigates the incorporation of biological processes such as bioremediation and phytoremediation with nanotechnology, highlighting both progress and existing constraints. This thorough examination highlights the advantages of various materials and compounds utilized in water filtration systems and pinpoints crucial areas for future investigation. In addition, the research examines high-quality materials mentioned in existing literature, emphasizing their substantial influence on the progress of membrane technologies. The offered insights seek to optimize the efficiency and efficacy of contemporary water treatment systems, thereby contributing to the worldwide provision of uncontaminated and secure water resources.

The BCS class II (Biopharmaceutical Classification System) niclosamide has shown promising anticancer activity for colorectal cancer. However, its low water solubility compromises its oral absorption and systemic action. Incorporating niclosamide in nanoemulsion allows to optimize its cell uptake and tumor penetration. This study aimed at the development, physicochemical characterization, and in vitro anticancer activity of a niclosamide nanoemulsion, with HCT-116 as the cell model. Medium- and long-chain lipids were tested to prepare the nanoemulsions, obtained by high-pressure homogenization. Design of experiments was used to optimize the formulations, which were subjected to a stability study at 30 °C/75% relative humidity (RH) and 4 °C. Nanoemulsion efficacy was evaluated in an HCT-116 viability assay and 3D cell culture model. Medium-chain lipids provided better solubility results than long-chain. Miglyol® 812 and poloxamer 188 proved to be suitable components for the system. Niclosamide nanoemulsion (~ 200 nm) was stable for 56 days, presenting monomodal particle size distribution. The cell viability assay with HCT-116 cell line demonstrated that niclosamide cytoxicity was both time and concentration dependent. In the 3D cell culture model, size and zeta potential may have influenced drug penetration in the spheroid. Incorporating the drug substance in a nanostructured system was pivotal to potentiate niclosamide activity. Our results encourage further research to understand and optimize niclosamide performance as an anticancer drug substance aiming at its repositioning.

Graphical Abstract

Due to the rapid advancement in civilization and industrialization, there is an increase in the contamination of water due to dumping or accumulation of waste and harmful products in water resources. As a result, freshwater scarcity has become a major concern worldwide and needs to be addressed by finding ways to avoid, remove, or degrade these harmful contaminants in water. Metal–organic frameworks (MOFs) act as a potential and promising candidate for removing and degrading harmful organic dyes from wastewater. In this study, we successfully synthesized a new Zirconium-based MOF (Zr-MOF) by the solvothermal method using melamine and trimesic acid as organic moieties. The synthesized Zr-MOF particles are monodispersed in nature with an average hydrodynamic diameter of 200 nm as demonstrated by dynamic light scattering (DLS) measurements. Its formation and stability were confirmed by spectroscopic techniques including FTIR and XRD methods. The formed MOF displayed tremendous capability in degrading cationic as well as anionic dyes. It shows a surface area of 795.64 m²/g. The Zr-MOF shows adsorption percentages of 97.2% and 80.3% for Congo Red (CR) and Toluidine Blue (TB) respectively. Owing to a positively charged surface, the Zr-MOF showed more potential for adsorption of anionic dye because of electrostatic interactions. These MOFs showed 96.4% and 57.9% reusability in the second cycle for CR and TB, respectively, indicating their strong affinity towards anionic dye (CR). We have also reported the adsorption kinetics, stability, and reusability of Zr-MOF in the efficient removal of pollutants from water in this manuscript. Hence, with recent advancements and developments, this study may offer new inspirations for tuning and designing the membrane with superior dye removal which can be extended to laboratory and industrial usage.

Ba_0.5-xSr_0.5Pb_xFe₁₂O₁₉ hexaferrites (x = 0, 0.1, 0.2, 0.3, and 0.5) prepared by the co-precipitation method, revealed the formation of M-type hexaferrites with crystallite sizes varying from 42.81 to 60.96 nm. Fourier transform infrared spectra (FTIR) indicated the formation of hexaferrites. Scanning electron microscope (SEM) analysis confirmed hexagonal morphology. Transmission electron microscopy (TEM) micrographs, high-resolution transmission electron microscopy (HRTEM) pictures, and selected area electron diffraction (SAED) patterns further supported the nanoparticle characteristics. SAED analysis showed clear and well-defined circular rings, corresponding to the reflection planes observed in X-ray powder diffraction (XRD) analyses. X-ray photoelectron spectroscopy (XPS) was performed to examine the electronic structure, while energy-dispersive X-ray spectroscopy (EDX) investigation proved the elements’ existence. The direct optical energy band gaps (({mathrm{E}}_{mathrm{g}})), as determined through Tauc plots, decreased from 3.11 to 2.95 eV in an inversely proportional manner to D, indicating the quantum confinement effect. Photoluminescence (PL) spectra showed emissions at 335 nm for all synthesized compounds. The vibrational sample magnetometer (VSM) measurements showed strong ferromagnetic behavior, with a decrease in saturation magnetization (({mathrm{M}}_{mathrm{s}})) from 56.33 to 38.83 emu/g, coercive fields (({mathrm{H}}_{mathrm{c}})) from 4388.3 to 3289.3 G, and squareness ratios from 0.49 to 0.43. The decrease in coercivity (({mathrm{H}}_{mathrm{c}})) with Pb incorporation is attributed to significant demagnetizing-like interactions caused by a rise in particle size and a reduction in anisotropy energy rising from Pb doping. Effective crystalline anisotropy constants (({mathrm{K}}_{mathrm{eff}})) decreased from 2.37 × 10⁵ to 1.03 × 10⁵ Erg/g, categorizing the materials as hard magnets ideal for high-density magnetic recording plus permanent magnet production.

The influence of size on the dynamic magnetic hysteresis properties and dynamic phase transitions of Fe and (Fe_3O_4) 2D-circular nanodisks with varying diameters has been explored in the micromagnetic framework. This investigation is conducted under a sinusoidal dynamic magnetic field along the x-direction by solving the Landau-Lifshitz-Gilbert (LLG) equation with the OOMMF software at zero temperature. The dynamic hysteresis of nanodisks is profoundly impacted by both the frequency and amplitude of the applied external field, along with the particle size. As particle size decreases, there is an observed increase in the frequency values at which the transition to dynamic ordered frequency occurs in Fe nanodisks, whereas a decrease is noted in the transition frequency values of (Fe_3O_4) nanodisks.