Journal of Cluster Science最新文献

The transition metal clusters are promising components of single-molecule junctions (SMJs) as they have a large number of molecular orbitals (MOs) with different symmetry and degeneracy in near-Fermi-level region, suitable for electron transmission. The chalcogenide clusters Mo₆Q₈ (Q = S, Se, Te) have high symmetry and due to the different orientations (by Mo or Q atoms to electrodes) and chalcogen variation, the transmission function (T(E)) can be tuned to achieve the desired conductive properties. In the work, the energy positions of the T(E) peaks near the Fermi level were assigned to the MOs in SMJs with Mo₆Q₈ using the nonequilibrium Green’s function formalism (NEGF) within the framework of the density functional theory. The changes of T(E) functions and MOs depending on the distances between the terminal atoms of electrodes and the embedded molecule were investigated. It is shown that for the correct assignment of MOs with T(E) peaks, it is necessary to consider long distances, even longer than those typically believed to be chemically significant. The influence of the electronic structure, symmetry of molecular orbitals, and electrodes on the SMJ transmission function was revealed. Depending on the orientation of the cluster, a different number of MOs participate in the peak of T(E) near the Fermi level, which influences the properties of the SMJs. The data obtained may be useful in the design of SMJs based on octahedral chalcogenide clusters and in tuning their conductive properties.

In this study, g-C₃N₄/Zn-doped CuO nanocomposites were successfully synthesized by coprecipitation and thermal pyrolysis methods to evaluate their photocatalytic and antibacterial activities. The synthesized nanocomposites were comprehensively analyzed through X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectroscopy and photoluminescence techniques to evaluate their structural, chemical, morphological and optical properties. X-ray diffraction confirmed the successful incorporation of Zn-doped CuO and g-C₃N₄. The morphology showed a well-dispersed hybrid structure in which the components are in close interfacial contact. UV-Vis diffuse reflectance spectroscopy revealed a red shift and a narrow band gap in the g-C₃N₄/Zn-doped CuO nanocomposites compared to pure g-C₃N₄ and CuO, which significantly enhanced the light absorption ability. Photoluminescence analysis revealed the suppressed electron-hole pair recombination in the g-C₃N₄/Zn-doped CuO nanocomposites. The g-C₃N₄/Zn-doped CuO nanocomposites exhibited excellent photocatalytic performance, achieving up to 88.47% degradation of Rose Bengal dye within 120 min. Furthermore, g-C₃N₄/Zn-doped CuO nanocomposites exhibited significant antibacterial efficacy with larger zones of inhibition against Klebsiella pneumoniae (9 ± 0.41 mm) compared to Staphylococcus aureus (8 ± 0.52 mm) at a concentration of 100 μg.mL^-1. The enhanced performance can be attributed to the synergistic interaction between g-C₃N₄ and Zn-doped CuO, which improves the charge separation efficiency and also enhances the photocatalytic performance. This work highlights the potential of g-C₃N₄/Zn-doped CuO nanocomposites as efficient and sustainable materials for environmental and biomedical applications.

Janus particles are a unique class of micro-and nanostructures featuring dual-faced asymmetry, typically composed of chemically, physically, or functionally distinct regions. This anisotropy grants them stable interfacial orientation and imparts exceptional amphiphilicity, surface activity, and self-assembly behavior. However, precisely controlling their morphology and composition remains a major synthetic challenge. In this context, microfluidic technology has emerged as a powerful platform due to its ability to finely manipulate fluid dynamics and interfacial phenomena at the microscale. Widely applied in nanomaterials and drug delivery, microfluidics also offers significant advantages for the tailored synthesis of Janus particles. This review outlines the evolution of microfluidic techniques and highlights their unique strengths in fabricating Janus structures. Based on different mechanisms, microfluidic strategies are classified into two main categories: Droplet-Templated and Flash Nanoprecipitation. Recent advances in each method are discussed with emphasis on their fabrication features. In addition, the review explores the practical relevance of these methods in diverse fields, including Optical Display Technologies, Self-Propelled and Actively Controlled Microparticle Systems, and Biomedical Systems. This work aims to provide insights and references for the future development and functional deployment of Janus particles.

Oral candidiasis is an opportunistic infection that affects 30–50% of individuals. Available antifungal therapeutics pose challenges of poor solubility, low bioavailability, and inadequate retention at the application site. The present research aimed to develop an in-situ nanoemulgel (NEG) combining nanoemulsion (NE) with stimuli-responsive hydrogel-forming polymers for miconazole nitrate for enhanced efficacy. In due course, characterization of the formulation including in-vitro and ex-vivo release patterns along with cytotoxicity study and antifungal efficacy were evaluated to establish the safety and efficacy of the optimized formulation. Optimization of the NE formulation was performed using Box-Behnken statistical design with Phosal^®50PG, Cremophor-EL and isopropyl alcohol. The optimized NE had droplets of 118.7 ± 0.64 nm, a PDI of 0.165 ± 0.05, and a surface charge of − 15.54 ± 0.35mV, while the NEG had 152.2 ± 0.21 nm droplets, a PDI of 0.193 ± 0.07, and a surface charge of − 18.3 ± 0.49mV. The formulation’s viscosity, mucoadhesive properties, spreadability, and pH were 3028 ± 192.39cP, 37.61 g.sec, 14.02 ± 0.46 cm²/g and 6.46 ± 0.130, respectively. In-vitro drug release studies showed first-order kinetics indicating concentration-dependent release. Ex-vivo permeation studies across goat oral mucosa revealed 2.05-fold higher for NEG compared to marketed gel. The NEG’s steady-state flux was 2.04-fold higher than the marketed gel due to enhanced mucosal penetration. Furthermore, the results of the cytotoxicity studies on HaCaT cell lines are comparable to ex-vivo toxicity, confirming its safety on mucosal tissues. Finally, the NEG demonstrated superior antifungal efficacy compared to the marketed formulation, highlighting its potential for advancing oral candidiasis therapy. Therefore, the NEG approach demonstrates superior efficacy and safety compared to existing treatment, conferring a promising antifungal therapy.

Graphical Abstract

Background

The production and utilization of nanomaterials has been steadily expanding. This leads to significant exposure of the workforce to these materials during their work activities.

Methods

A comprehensive search across PubMed, Scopus, and Web of Science databases using keywords related to “occupational exposure” and “nanomaterials” was conducted. Initially, duplicates were eliminated, followed by a review based on title and abstract to exclude irrelevant items. the remaining documents underwent full-text examination for adherence to inclusion criteria. Out of 3,314 initial documents, 303 articles met the study’s criteria.

Findings

More than 30 countries had investigated the occupational exposure to nanomaterials, with the United States, Korea, and China at the top. Totally, nearly 30,000 employees were exposed to nanomaterials and more than 13,000 non-exposed employees were investigated. More than 70% of the studies were cross-sectional and the least attention was paid to long-term and cohort studies. Most of the studies were carried out, in environments producing engineered nanomaterials, environments with incidental nanomaterials, laboratory environments, and environments consuming nanomaterials, respectively. Metal-oxide, carbon-based, and metal nanomaterials were investigated more than other nanomaterials, respectively.

Conclusion

One crucial aspect of nanotechnology should be the evaluation of occupational exposure to nanomaterials. The majority of the research should focus on more hazardous nanomaterials that are produced and consumed in greater quantities. It is preferable for research to shift toward long terms and cohorts. It is advised that the safety, health, and environmental concerns of nanotechnology be given careful consideration and growth alongside other related areas.

Reactions of cesium salts of substituted nido-carborane anions [nido-5-Ph-7,8-C₂B₉H₁₁]^- (1) and [nido-5,6-Ph₂-7,8-C₂B₉H₁₀]^- (2) bearing bulky phenyl groups at boron atoms in the lower bent of carborane ligand with RuCl₂(PPh₃)dppb (3) in benzene solution led to the novel 18-e closo-ruthenacarboranes 3,3-(Ph₂P(CH₂)₄PPh₂)-3-H-3-Cl-9-Ph-12-X-closo-3,1,2-RuC₂B₉H₉ (X = H (4), Ph (5)). Reactions of the obtained complexes with carbon tetrachloride allowed to obtain corresponding 17-e Ru(III) complexes 3,3-(Ph₂P(CH₂)₄PPh₂)-3-Cl-9-Ph-12-X-closo-3,1,2-RuC₂B₉H₁₀ (X = H (7), Ph (8)). The reaction of 4 with isopropylamine in acetonitrile leads to the formation of the corresponding acetonitrile complex 3,3-(Ph₂P(CH₂)₄PPh₂)-3-CH₃CN-9-Ph-12-closo-3,1,2-RuC₂B₉H₁₀ (10). The novel ruthenacarborane clusters 5 and 8 were characterized by single crystal X-ray diffraction which unambiguously confirmed the proposed structures. The cyclic voltammetry studies of compounds 4 and 5 showed its ability to reversible reduction to the corresponding Ru(II) species.

Although essential amino acids play a critical role in biological and medical fields, only a limited number of computational studies on their interaction with nanocages have been reported in the literature. This study explores the potential of Be₁₂O₁₂ nanocage for detecting amino acids, specifically glycine, valine, leucine, methionine, threonine, and phenylalanine. The adsorption of these amino acids onto the Be₁₂O₁₂ structure is investigated using Density Functional Theory (DFT) calculations, employing the B3LYP-D3/def2-TZVP level of theory. The calculated adsorption energies for Gly_Be₁₂O₁₂, Val_Be₁₂O₁₂Leu_Be₁₂O₁₂, Met_Be₁₂O₁₂, Thr_Be₁₂O₁₂and Phe_Be₁₂O₁₂₂ in water phase (gas) are − 104.3 (-133.8) kJ·mol⁻¹, -108.1 (-137.7) kJ·mol⁻¹, -109.4 (-139.4) kJ·mol⁻¹, -121.4 (-169.5) kJ·mol⁻¹, -120.2 (-150.5) kJ·mol⁻¹, and − 117.7 (-151.9), respectively. To characterize the nature of interactions in the studied complexes, several analyses were performed, including Interaction Region Indicator (IRI), charge decomposition analysis (CDA), and energy decomposition analysis (EDA). Additionally, quantum electronic parameters, such as the density of states (DOS), HOMO-LUMO gaps, and percentage change in the HOMO-LUMO gap, along with geometric properties, were calculated to assess the stability and structural characteristics of the complexes. The results show that Met_Be₁₂O₁₂, Thr_Be₁₂O₁₂, and Phe_Be₁₂O₁₂ exhibit higher binding energies than the other complexes, indicating a stronger interaction with the Be₁₂O₁₂ nanocage. The adsorption analysis of multiple amino acid molecules indicates that the Be₁₂O₁₂ nanocage exhibits an optimal adsorption capacity, with the ability to adsorb up to four molecules of leucine and valine, three molecules of phenylalanine and glycine, and a single molecule of methionine and threonine. This study provides theoretical insights into the interactions between Be₁₂O₁₂ and amino acids, enhancing the understanding of their nature, and contributing therefore to the advancement of biosensor development for amino acid detection.

This study investigates the control of Alternaria alternata, a fungal pathogen accountable for the post-harvest deterioration of tomato fruits, using green-synthesized copper oxide nanoparticles (CuO-NPs) and zinc oxide nanoparticles (ZnO-NPs). The pathogenic fungi (5 isolates) were isolated from symptomatic tomato fruits collected in Riyadh, Saudi Arabia. All isolates were identified through morphological and molecular techniques, including ITS region sequencing and phylogenetic analysis. The green synthesis of CuO-NPs and ZnO-NPs was achieved using orange peel extract (OPE), and the nanoparticles were characterized using SEM, EDX, FT-IR, XRD, and TEM. The results confirmed the formation of spherical NPs with particle sizes of 23.80 and 28.80 nm for ZnO-NPs and CuO-NPs, respectively. Using the agar dilution method, the two NPs exhibited significant dose-dependent antifungal activity toward A. alternata. At a concentration of 2 mg/mL, the CuO-NPs and ZnO-NPs induced a fungal growth inhibition of about 1.35 ± 0.45 mm and 1.85 ± 0.36 mm, compared to the untreated control (5.2 ± 0.23 mm). Interestingly, the combined application of CuO-NPs and ZnO-NPs resulted in significantly reduced antifungal efficacy (3.11 ± 0.45 mm). This study highlights the potential of green-synthesized NPs as eco-friendly antifungal agents for controlling post-harvest Alternaria alternata infection. It also emphasizes the need for further research to optimize their synergistic applications.

In this study, Mo-based transition metal oxide nanoparticles MoO₃ (MO), CuMoO₄ (CMO), FeMoO₄ (FMO), and Cu_1.815Fe_1.815Mo₃O₁₂ (CFMO) were synthesized via a sol-gel technique. Further, evaluated for their photo-Fenton dye degradation performance against Methylene Blue dye under visible light irradiation using H₂O₂ as an oxidant. Structural, optical, morphological, and surface analyses confirmed the formation of pure-phase nanoparticles with flake-like morphology and tunable band gaps. Optical band gap values decreased from 2.93 eV (MoO₃) to 1.68-1.80 eV for ternary Cu_1.815Fe_1.815Mo₃O₁₂, enhancing visible light absorption. Among all, the ternary oxide with 0.1 M Mo exhibited the highest degradation efficiency of 97.6% within 60 minutes, outperforming the binary (CMO₄: 97.1%, FMO₄: 94.1%) and primary (MoO₃: 98.1% in 180 min) systems. Kinetic studies confirmed first-order degradation behavior with the highest rate constant of 5.9 × 10^-2 min^-1 and shortest half-life of 11.7 minutes for the optimal ternary catalyst. Scavenger experiments further revealed that hydroxyl radicals (•OH) are the dominant reactive species, with moderate contributions from superoxide radicals (•O₂^-) and photogenerated holes (h⁺). The CFMO nanoparticles also retained their catalytic activity after five consecutive cycles, indicating excellent reusability. These findings demonstrate the promising potential of Mo-incorporated ternary oxide nanoparticles as efficient, cost-effective, and recyclable photo-Fenton catalysts for environmental wastewater remediation.

Systemic toxicity and poor tumor specificity remain significant challenges in chemotherapy, necessitating the development of advanced drug delivery systems. Hydrogels have emerged as promising platforms for oral drug delivery, offering targeted and sustained release. In this study, we synthesized a cluster-shaped single-network (SN) nanogel via inverse miniemulsion polymerization, explicitly designed to mimic the dynamic behavior of polymer clusters, for colon-specific oral administration. The unique cluster-like organization of the Alg-PDMAEMA nanogel not only increases its surface area but also contributes to its pH- and temperature-responsive behavior, closely emulating physiological conditions. The nanogel achieved a drug loading efficiency of 87% and demonstrated a cumulative in vitro release of 92% over 22 h at pH 7.4 and 37 °C, while negligible release under gastric conditions ensured site-specific delivery. Comprehensive characterization, including FESEM, DLS, TGA, BET, FT-IR, and zeta potential analyses, confirmed the nanogel’s uniform nanoscale size, high surface area, and thermal stability. Kinetic and thermodynamic analyses revealed a non-Fickian diffusion mechanism, indicative of a combination of diffusion- and swelling-controlled release that parallels the behavior of molecular clusters. Cytotoxicity assays further demonstrated that DOX-loaded nanogels reduced MCF-7 cell viability by 74% compared to free DOX while maintaining minimal toxicity toward normal MCF-10 A cells. These findings suggested the potential of cluster-inspired SN Alg-PDMAEMA nanogels as an innovative platform for oral anticancer drug delivery, enhancing therapeutic efficacy and offering new insights into the role of cluster dynamics in controlled drug release.