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The elongation of metallic nanoparticles (NPs) embedded in a dielectric matrix after irradiation with swift heavy ions is a phenomenon that has been known for several years. However, the precise mechanism behind this deformation process is still not fully understood, primarily due to the dearth of information during intermediate stages of deformation. In this study, we report the continuation of our previous work [Peña-Rodríguez et al., Sci. Rep. 7(1), 922 (2017)], exploiting the strong dependence of the localized surface plasmon resonance on the aspect ratio of elongated metal NPs to study the elongation kinetics in situ. In situ optical absorption spectra were measured using a polarizing beam splitter to separate the longitudinal and transverse plasmon modes of the anisotropic NPs. Then, the detailed geometrical and compositional parameters were determined from a fit of these spectra. The use of linearly polarized light allowed for a more accurate analysis of the elongation kinetics, particularly useful in the first stages, where longitudinal and transverse modes overlap. [ABSTRACT FROM AUTHOR]

Granular metals (GMs), consisting of metal nanoparticles separated by an insulating matrix, frequently serve as a platform for fundamental electron transport studies. However, few technologically mature devices incorporating GMs have been realized, in large part because intrinsic defects (e.g., electron trapping sites and metal/insulator interfacial defects) frequently impede electron transport, particularly in GMs that do not contain noble metals. Here, we demonstrate that such defects can be minimized in molybdenum–silicon nitride (Mo–SiNx) GMs via optimization of the sputter deposition atmosphere. For Mo–SiNx GMs deposited in a mixed Ar/N2 environment, x-ray photoemission spectroscopy shows a 40%–60% reduction of interfacial Mo-silicide defects compared to Mo–SiNx GMs sputtered in a pure Ar environment. Electron transport measurements confirm the reduced defect density; the dc conductivity improved (decreased) by 104–105 and the activation energy for variable-range hopping increased 10×. Since GMs are disordered materials, the GM nanostructure should, theoretically, support a universal power law (UPL) response; in practice, that response is generally overwhelmed by resistive (defective) transport. Here, the defect-minimized Mo–SiNx GMs display a superlinear UPL response, which we quantify as the ratio of the conductivity at 1 MHz to that at dc, Δ σ ω. Remarkably, these GMs display a Δ σ ω up to 107, a three-orders-of-magnitude improved response than previously reported for GMs. By enabling high-performance electric transport with a non-noble metal GM, this work represents an important step toward both new fundamental UPL research and scalable, mature GM device applications. [ABSTRACT FROM AUTHOR]

Computational modeling of plasmon-mediated molecular photophysical and photochemical behaviors can help us better understand and tune the bound molecular properties and reactivity and make better decisions to design and control nanostructures. However, computational investigations of coupled plasmon–molecule systems are challenging due to the lack of accurate and efficient protocols to simulate these systems. Here, we present a hybrid scheme by combining the real-time time-dependent density functional theory (RT-TDDFT) approach with the time-domain frequency dependent fluctuating charge (TD-ωFQ) model. At first, we transform ωFQ in the frequency-domain, an atomistic electromagnetic model for the plasmonic response of plasmonic metal nanoparticles (PMNPs), into the time-domain and derive its equation-of-motion formulation. The TD-ωFQ introduces the nonequilibrium plasmonic response of PMNPs and atomistic interactions to the electronic excitation of the quantum mechanical (QM) region. Then, we combine TD-ωFQ with RT-TDDFT. The derived RT-TDDFT/TD-ωFQ scheme allows us to effectively simulate the plasmon-mediated "real-time" electronic dynamics and even the coupled electron–nuclear dynamics by combining them with the nuclear dynamics approaches. As a first application of the RT-TDDFT/TD-ωFQ method, we study the nonradiative decay rate and plasmon-enhanced absorption spectra of two small molecules in the proximity of sodium MNPs. Thanks to the atomistic nature of the ωFQ model, the edge effect of MNP on absorption enhancement has also been investigated and unveiled. [ABSTRACT FROM AUTHOR]

The influence of a dielectric layer with an embedded 2D array of metal nanoparticles on the spectral characteristics of a distributed Bragg reflector is theoretically studied and numerically validated. A significant dependence of the reflectivity of the hybrid structure on the location of the nanoparticle array relative to the maxima and minima of the optical field in the surface dielectric layer is demonstrated. It is found that the application of a dilute ensemble of nanoparticles (the interparticle distance is from 2 to 5 times larger than the nanoparticle size) in the region of high optical field localization makes it possible to obtain a total suppression of reflection in the photonic bandgap range of distributed Bragg reflector. Contrariwise, if the optical field is almost zero at the nanoparticle array location, its impact on the scattered light is negligible, that is, the resonant nanoparticles are masked by a highly reflective photonic structure. The target wavelength can be tuned inside the photonic bandgap range by adjusting the shape of nanoparticles and interparticle distance in the array. [ABSTRACT FROM AUTHOR]

InN holds great promise for a wide range of applications, including broadband optical devices, high-frequency electronic devices, and serving as a substrate for highly sensitive gas detectors and efficient catalysts. Nevertheless, production of high-quality InN thin films through epitaxy has remained a significant challenge. This is primarily due to complexities arising from the low dissociation temperature and the high N2 equilibrium pressure of InN, which lead to formation of numerous nitrogen vacancies and a propensity to generate indium metal nanoparticles. Efficacy of the indium bilayer pre-deposition method for InN film growth has been established in prior studies. In this work, we introduce a specialized hydrogen insertion method to further enhance nitridation of the indium bilayer. The corresponding kinetic mechanism has been demonstrated through theoretical simulations and practical epitaxy experiments, leading to the development of an optimized hydrogen insertion process. This research represents a substantial improvement over existing InN epitaxial methods that involve control of the indium bilayer and introduces a novel mechanism for enhancing InN heteroepitaxy. [ABSTRACT FROM AUTHOR]

Electromagnetic shielding is a critical function in various technologies, which is ideally achieved using a metal that reflects all incident radiation below its plasma frequency. Using high-resolution finite difference frequency domain simulations at microwave/RF frequencies, we show that the same efficacy can be achieved using a disordered collection of metal nanoparticles embedded in a flexible material. The mechanism underlying the reflection in the composite material is wave localization, disallowing the propagation of radiation up to the plasma frequency of the metal that constitutes the particles. We realize such a biopolymer composite using DNA–CTMA (deoxyribonucleic acid–cetyltrimethylammonium complex) as a support structure for Ag nanoparticles. This biopolymer composite exhibits an extremely high shielding effectiveness, close to that of a metal slab, because of Anderson localization of the electromagnetic waves. [ABSTRACT FROM AUTHOR]

Strong light–matter interactions significantly modify the optical properties of molecules in the vicinity of plasmonic metal nanoparticles. Since the dimension of the plasmonic cavity approaches that of the molecules, it is critical to explicitly describe the nanoparticle junctions. In this work, we use the discrete interaction model/quantum mechanical (DIM/QM) method to model the coupling between the plasmonic near-field and molecular excited states. DIM/QM is a combined electrodynamics/quantum mechanical model that uses an atomistic description of the nanoparticle. We extend the DIM/QM method to include the local field effects in the sum-over-state formalism of time-dependent density functional theory. As a test of the method, we study the interactions between small organic chromophores and metal nanoparticles. In particular, we examine how the inclusion of multiple electronic transitions and intermolecular interactions modify the coupling between molecules and nanoparticles. Using the sum-over-state formalism of DIM/QM, we show that two-state models break down when the plasmon excitation is detuned from the molecular excitations. To gain further insight, we compare the simple coupled-dipole model (CDM) with the DIM/QM model. We find that CDM works well for simple systems but fails when going beyond the single molecule or single nanoparticle cases. We also find that the coupling depends strongly on the site of the nanoparticle in which the chromophore couples to. Our work suggests the importance of explicitly describing the cavity to capture the atomistic level local field environment in which the molecule strongly couples to. [ABSTRACT FROM AUTHOR]

Supported metallic nanoparticles play a central role in catalysis. However, predictive modeling is particularly challenging due to the structural and dynamic complexity of the nanoparticle and its interface with the support, given that the sizes of interest are often well beyond those accessible via traditional ab initio methods. With recent advances in machine learning, it is now feasible to perform MD simulations with potentials retaining near-density-functional theory (DFT) accuracy, which can elucidate the growth and relaxation of supported metal nanoparticles, as well as reactions on those catalysts, at temperatures and time scales approaching those relevant to experiments. Furthermore, the surfaces of the support materials can also be modeled realistically through simulated annealing to include effects such as defects and amorphous structures. We study the adsorption of fluorine atoms on ceria and silica supported palladium nanoparticles using machine learning potential trained by DFT data using the DeePMD framework. We show defects on ceria and Pd/ceria interfaces are crucial for the initial adsorption of fluorine, while the interplay between Pd and ceria and the reverse oxygen migration from ceria to Pd control spillover of fluorine from Pd to ceria at later stages. In contrast, silica supports do not induce fluorine spillover from Pd particles. [ABSTRACT FROM AUTHOR]

For the first time, the dominant magnetoelectric activity of ZIF-67-derived carbonaceous microparticles embedded with Co nanoparticles and distinctive magnetothermal effect of MIL-88B-derived Fe3O4 nanocubes decorated on carbonaceous microrods, respectively, were explored to be controlled by the structure of the MOF-derived electrically conductive carbonaceous matrix and metal nanoparticles. [ABSTRACT FROM AUTHOR]

AbstractWe have previously demonstrated that exposure to cobalt nanoparticles (Nano-Co) caused extensive interstitial fibrosis and inflammatory cell infiltration in mouse lungs. However, the underlying mechanisms of Nano-Co-induced pulmonary fibrosis remain unclear. In this study, we investigated the role of high-mobility group box 1 (HMGB1) in the epithelial cell-fibroblast crosstalk in Nano-Co-induced pulmonary fibrosis. Our results showed that Nano-Co exposure caused remarkable production and release of HMGB1, as well as nuclear accumulation of HIF-1α in human bronchial epithelial cells (BEAS-2B) in a dose- and a time-dependent manner. Pretreatment with CAY10585, an inhibitor against HIF-1α, significantly blocked the overexpression of HMGB1 in cell lysate and the release of HMGB1 in the supernatant of BEAS-2B cells induced by Nano-Co exposure, indicating that Nano-Co exposure induces HIF-1α-dependent HMGB1 overexpression and release. In addition, treatment of lung fibroblasts (MRC-5) with conditioned media from Nano-Co-exposed BEAS-2B cells caused increased RAGE expression, MAPK signaling activation, and enhanced expression of fibrosis-associated proteins, such as fibronectin, collagen 1, and α-SMA. However, conditioned media from Nano-Co-exposed BEAS-2B cells with HMGB1 knockdown had no effects on the activation of MRC-5 fibroblasts. Finally, inhibition of ERK1/2, p38, and JNK all abolished MRC-5 activation induced by conditioned media from Nano-Co-exposed BEAS-2B cells, suggesting that MAPK signaling might be a key downstream signal of HMGB1/RAGE to promote MRC-5 fibroblast activation. These findings have important implications for understanding the pro-fibrotic potential of Nano-Co. [ABSTRACT FROM AUTHOR]

This paper investigates the enhanced photoluminescence of CsPbX3 by the localized surface plasmon (LSP) of Ag nanoparticles. The Ag nanoparticles with different sizes were obtained by annealing Ag thin films at different temperatures. Then the Ag/PMMA/perovskite structure was fabricated to realize the exciton-LSP coupling effect, and enhancement was found for wavelength-tunable CsPbX3 films. When the Ag film is heated to 200∘C, the maximum enhancement factor of LSP is 6.03. The LSP coupling effect induces the slight blue shift of the fluorescence emission center which is caused by the limitation of electron free trajectories under the LSP resonance frequency of Ag nanoparticles. As the gap between nanoparticles decreases, the absorption cross-section increases, and the scattering rate of electrons on the surface of metal nanoparticles greatly exceeds the internal scattering rate, causing the LSP resonance frequency to shift to the blue region, resulting in a blue shift of the PL spectrum. [ABSTRACT FROM AUTHOR]

The sluggish kinetics and thermodynamic stability associated with LiAlH 4 have posed significant obstacles to its practical application. Herein, we have designed a general method for preparing a series of hollow 3D flower-like composite, denoted as M-NC@TiO 2 (M = Ni, Co, Fe, Cu), which serve as highly efficient catalysts for the dehydrogenation of LiAlH 4. These composites feature TiO 2 hollow spheres as substrates to induce the growth of MOF nanosheets, leading to the regular arrangement of carbon nanosheets anchored with metal nanoparticles M on the TiO 2 sphere surface after calcination treatment. Evidently, M-NC@TiO 2 exerts a discernible enhancement on the dehydrogenation kinetics of LiAlH 4. LiAlH 4 -7wt% Ni-NC@TiO 2 system begins to release hydrogen at a notably lowered temperature of 56.3 °C, with a total amount of hydrogen released of 7.19 wt% before reaching 300 °C. Subsequent investigations showed that the enhanced hydrogen storage performance can be attributable to the in-situ formation of the metal compounds, the fine size and high dispersion of metallic nanoparticles, and the synergistic effect between TiO 2 and M nanoparticles. This work not only provides an effective general way to synthesize catalysts for improving the hydrogen storage performance of aluminum-based hydrogen storage materials, but also augments our understanding of hydrogen storage mechanisms. [ABSTRACT FROM AUTHOR]

Ta 2 O 5 /Pd hybrid microspheres were readily synthesized via a one-step thermal solution process employing a template composed of glucose carbon spheres, yielding a structure characterized by a rough and porous surface. This morphology offers an expanded contact area and increased sites for ethanol reactions of Ta 2 O 5 /Pd hybrid microspheres. At room temperature (25 °C), the Ta 2 O 5 /Pd hybrid microspheres exhibited responsiveness to ethanol concentrations ranging from 50 to 700 ppm, displaying a linear response pattern to a narrow concentration gradient of 90–120 ppm. The hybrid exhibited notable sensitivity, manifesting a response value of 5.1–100 ppm ethanol. In addition, they displayed less responsiveness to other VOCs gases, were minimally affected by humidity, and maintained gas-sensitive stability for 30 days, demonstrating excellent selectivity and long-term stability. Based on the fitting curve analysis, the material theoretically demonstrated the ability to detect ethanol at concentrations as low as 101 ppb. Ta 2 O 5 /Pd hybrid microspheres modified by glucose carbon sphere templates and noble metal nanoparticles are promising candidates for ethanol room temperature sensing, providing new insights into the development of room temperature sensing. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) have emerged as crucial components in precision drug delivery, presenting innovative opportunities to significantly enhance therapeutic efficacy and targeting accuracy. This review investigates recent developments in the engineering of metal NPs, emphasizing their distinctive properties and novel applications in drug delivery systems. A comprehensive analysis is performed on gold, silver, iron, and zinc oxide NPs, emphasizing their exceptional physicochemical properties and enhanced drug‐loading capacities. These features collectively enable the development and implementation of targeted and controlled drug delivery systems, indicating a new era of advanced therapeutic approaches. This review article accomplishes this by reflecting on the transformative potential of metal NPs, envisioning heightened efficacy, minimized side effects, and improved patient outcomes within the dynamic landscape of drug delivery platforms. [ABSTRACT FROM AUTHOR]

A direct current (DC) arc discharge is a widely used method for large-scale production of metal nanoparticles, core–shell particles, and carbon nanotubes. Here, the growth of iron nanoparticles is explored in a modified DC arc discharge. Iron particles are produced by the evaporation of an anode, made from low-carbon steel. Methane admixture into argon gas serves as a carbon source. Electron microscopy and elemental analysis suggest that methane and/or products of its decomposition adhere to iron clusters forming a carbon shell, which inhibits iron particle growth until its full encapsulation, at which point the iron core growth is ceased. Experimental observations are explained using an aerosol growth model. The results demonstrate the path to manipulate metal particle size in a hydrocarbon arc environment. [ABSTRACT FROM AUTHOR]

ABSTRACT Palladium nanoparticles immobilized on ZIF 67‐derived porous CoOx were prepared by wet‐impregnation method, followed by calcination at different temperatures. The calcination temperature has been employed to effectively manipulate the size of metal nanoparticles, where higher calcination temperatures resulted in larger sizes. The experimental results revealed that by manipulating the calcination temperature, the synthesis of palladium nanoparticles with varying sizes could be effectively controlled. Increasing the calcination temperature resulted in larger particle sizes. At a calcination temperature of 350°C, the synthesis process produced the smallest palladium nanoparticles, averaging 1.35 nm in size, facilitating the reaction between aryl halides and arylboronic acids with yields ranging from 83% to 99%. Furthermore, these nanoparticles demonstrated superior catalytic activity and recyclability. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) stand out owing to conspicuous catalytic activity, optical and electromagnetic properties, with applications ranging from photocatalysis to biosensor and photoelectric devices. Although photocatalysis with TiO2 has emerged as a promising technique for preparing MNPs, the low photocatalytic efficiency of TiO2 limits its practical utilization. Herein, a rapid photoreduction approach is presented to prepare MNPs under UV and visible light based on polydopamine (PDA)/TiO2 composite surface. It found that the PDA‐modified TiO2 substrate can greatly enhance the photocatalytic efficiency and stability of MNPs, leading to rapid and highly‐controllable preparation of MNPs. By this method, various Ag, Au, and Pd patterns with controllable metallization degree can be easily fabricated. In addition, the substrate can be effectively recycled through rapid photobleaching. This method will have a promising future in the preparation of MNPs for various applications. [ABSTRACT FROM AUTHOR]

In recent years, magnetic metal nanoparticles (NPs)/carbon nanofibers (CNFs) composites have become very promising electromagnetic waves (EMWs) absorbers. However, how to achieve controllable growth of magnetic metals in CNFs is still an urgent problem to be solved. Herein, we reported a pore-confined strategy for constructing the porous Co/CoO/CNFs. By introducing different amounts of acetone (0.20 g, 0.30 g and 0.40 g) into the aqueous phase spinning solution to construct the porous structure, we achieved uniform distribution of Co/CoO NPs and ultimately obtained the porous Co/CoO/CNFs microwave absorbers (MAs) with excellent microwave absorption performance. Thanks to the excellent impedance matching and enhanced polarization loss, the porous Co/CoO/CNFs obtained the minimum reflection loss (RL) of −52.2 dB with a thickness of 3.0 mm, and the effective bandwidth (EBW) was 3.02 GHz when the acetone addition in the spinning solution was 0.30 g. Therefore, the pore-confined strategy proposed herein is conducive to the design of the MAs with excellent performance and low infilling rates based on CNFs. Furthermore, the porous structure of CNFs also improves the lightweight performance of the MAs. [ABSTRACT FROM AUTHOR]

A novel inorganic‐organic‐inorganic ternary bioactive material formulated on antimicrobial peptide‐based polymer has been reported. Supramolecular approach has been employed to incorporate molecularly crowded tyrosine‐based polymer stabilized silver nanoparticles into membrane bound vesicles exploiting polyoxometalate‐triggered surface templating strategy. Utilizing the covalent reversible addition fragmentation chain transfer (RAFT) polymerization and exploiting templated supramolecular architectonics at biopolymer interface, the bioactive ternary polymeric nanohybrids have been designed against Shigellosis leveraging the antibacterial activities of silver nanoparticle, cationic amphiphilic tyrosine polymer and inorganic polyoxometalate. The detail investigation against Shigella flexneri 2a cell line demonstrates that the collaborative mechanism of the ternary hybrid composite enhances the bactericidal activity in comparison to only polyoxometalate and polymer stabilized silver nanoparticle with an altered mechanism of action which is established via detailed biological analysis. [ABSTRACT FROM AUTHOR]

Purpose: The antibacterial properties of silver nanoparticles (AgNPs) are extensively identified. In large quantities, they might be harmful. So many fields of nanotechnology have shown a great deal of interest in the development of an environmentally friendly, efficient method for synthesizing metal nanoparticles. Because of its antibacterial and antifungal properties toward a wide range of microbes, chitosan silver nanoparticles (AgNPs@Cs) constitute a newly developing class of bio-nanostructured hybrid materials. Furthermore, the use of photothermal therapy (PTT) has been suggested as a means of elimination of germs. These light-stimulated treatments are minimally invasive and have a few side effects. In the present work, the antibacterial effect of AgNPs at low concentrations; prepared by chemical and green methods as antimicrobial and photothermal agents in photothermal therapy; with laser irradiation were explored as combined treatment against MRSA, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Methods: Silver nanoparticles were produced in two ways. First, by sodium borohydrides, second, by chitosan (as a natural eco-friendly reducing, and capping agent). The nanostructure of AgNPs and AgNPs@Cs was confirmed by UV–visible spectrometer, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIRs), and direct light scattering (DLS). The antibacterial activity of the prepared nanoparticles and the laser irradiation was tested against three bacterial species of zoonotic importance; MRSA, Pseudomonas aeruginosa, and Klebsiella pneumoniae; and was evaluated by measuring their minimum inhibitory concentrations (MIC). Results: Silver nanoparticles produced by the two methods had spherical shapes with nearly the same particle size. The analysis of DLS showed that AgNPs were very stable with zeta potential − 28.8 mv, and 47.7 mv by chemical and chitosan synthesis, respectively. Furthermore, AgNPs@Cs showed higher antibacterial activity toward the tested bacterial species than AgNPs by chemical method. Additionally, the bacterial viability using photothermal laser therapy was reduced compared to laser and AgNPs alone. The bactericidal activities were higher when laser diode was coupled with AgNPs@Cs than by chemical reduction. Conclusion: The laser combined treatment had a higher antimicrobial effect than AgNPs alone or laser irradiation alone. [ABSTRACT FROM AUTHOR]

The versatility of aza- and oxa-heterocyclic compounds has garnered significant attention in recent times. A large number of currently approved pharmaceutical products include nitrogen- and oxygen-containing heterocycles. Recent nanotechnological developments have propelled an upsurge in the applications of nanocatalysis for heterocyclic synthesis. Metal nanoparticles (MNPs) have emerged as promising catalysts for the synthesis of aza- and oxa-heterocycles owing to their unique physicochemical properties. Various MNPs including gold, silver, nickel and palladium have been evaluated for their catalytic activities in different reaction types, including cyclisation, coupling, hydrogenation and oxidative transformations. The MNPs have exhibited remarkable catalytic efficiency when utilised under optimal conditions. These catalysts have showcased high reusability and recyclability, yielding satisfactory amounts of the desired heterocyclic compound. The present work provides a detailed overview of recent advances in the area of MNP-assisted synthetic construction of aza- and oxa-heterocycles, published during the previous calendar year, 2022. The review serves as a valuable resource and also paves the way for future investigations in the development of novel catalytic strategies for heterocycle synthesis. 1 Introduction 2 Nanocatalysis 3 Aza- and Oxa-Heterocycle Synthesis Catalysed by MNPs 3.1 AuNPs 3.2 CuNPs 3.3 CoNPs 3.4 FeNPs 3.5 NiNPs 3.6 PdNPs 3.7 PtNPs 3.8 SiNPs 3.9 ZnNPs 3.10 Bimetallic NPs 3.11 Other MNPs 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion Metal nanoparticles (MNPs) labeled with radioisotopes (RIs) are utilized as radio‐enhancers due to their ability to amplify the radiation dose in their immediate vicinity. A thorough understanding of nanoscale dosimetry around MNPs enables their effective application in radiotherapy. However, nanoscale dosimetry around MNPs still requires further investigation.This study aims to provide insight into the radio‐enhancement effects of MNPs by elucidating nanoscale dosimetry surrounding MNPs labeled with Auger‐emitting RIs. We particularly focus on distinguishing the respective dose contributions of photons and electrons emitted by Auger‐emitting RIs in the context of dose enhancement.A 50 nm diameter NP of silver (Ag) core and gold (Au) shell (Ag@Au NP) was assumed to emit mono‐energetic electrons and photons (3, 5, 10, 20, and 30 keV), or the energy spectrum corresponding to one of three Auger‐emitting RIs (103Pd, 125I, and 131Cs) from the Ag core. Nanoscale radial dose distributions around a single radioactive Ag@Au NP were evaluated in spherical shells of water. Monte Carlo simulations were conducted using single‐event and track structure transport methods implemented in MCNP6.2 and Geant4‐DNA‐Au physics, respectively. To evaluate the extent of radio‐enhancement by the Ag@Au NP, two scenarios were considered: Ag@Au NPs (Au shell included) and Ag@water NPs (Au shell replaced by water).The radial doses of 10, 20, and 30 keV electrons estimated by both codes were comparable. However, the radial doses of 3 and 5 keV electrons by MCNP6.2 were much larger near the NP surface than those by Geant4. There was a dose enhancement of a few % to tens % by the Au shell in the region of the NP surface to 10 µm, depending on the electron energy. The radial doses of photons with the Au shell were higher up to their secondary electron ranges than those without the Au shell. The maximum dose enhancement factor of photons occurred at 20 keV and was 63.4 by MCNP6.2 and 50.5 by Geant4. The overall radial doses of electrons were 1–2 orders of magnitude larger than those of photons. As a result, in cases of RIs emitting both electrons and photons, the radial doses up to electron ranges were dominantly governed by electrons. The dose enhancement estimated by both codes for the RIs ranged from a few % except in the immediate vicinity of the NP surface.Given the dominant contribution of electrons to radial doses of MNP labeled with Auger‐emitting RIs, physical dose enhancement expected by interactions with photons was hindered. Since there are no available RIs emitting exclusively photons, achieving enhanced physical doses within a cell through a combination of MNPs and RIs appears currently unattainable. The radial doses of photons near the NP surface exhibited considerable discrepancies between the codes, primarily attributed to low‐energy electrons. The difference may arise from higher cross‐sections of Au inelastic scattering in Geant4‐DNA‐Au compared to MCNP6.2. [ABSTRACT FROM AUTHOR]

The re-evaluation of animals, plants, and microorganisms for green synthesis has revolutionized the fabrication of metallic nanoparticles (MNPs). Green synthesis provides more biocompatibility compared to chemically synthesized MNPs, which make them ideal for diverse biological applications, especially in biomedicine. Various organisms have been extensively studied for green synthesis. Interestingly, angiosperms, algae, and animal-derived biomaterials like chitin and silk have shown a prominent role in synthesizing these nanoparticles. Moreover, bacteria, viruses, and fungi serve as sources of reducing agents, further expanding green synthesis possibilities. Despite progress, research on natural reducing agents remains relatively limited, with only a few exceptions such as tea and neem plants receiving attention. Green-synthesized nanoparticles have diverse applications in various fields. In biomedicine, they enable drug delivery, targeted therapies, and bio-imaging due to their enhanced biocompatibility. Some MNPs also exhibit potent antimicrobial properties, aiding in disease control and eco-friendly disinfection. Furthermore, green nanoparticles contribute to environmental remediation by purifying water and serve as sensitive biosensors for diagnostics and environmental monitoring. This review will provide the recent progress and advancements in the field of green synthesis (GS) of nanoparticles. It will also analyze the key characteristics and evaluate the advantages and disadvantages of GS compared to chemical synthesis. [ABSTRACT FROM AUTHOR]

Subnanometer metal clusters show advantages over conventional metal nanoparticles in numerous catalytic reactions owing to their high percentage of exposed surface sites, abundance of under‐coordinated metal sites and unique electronic structures. However, the applications of subnanometer metal clusters in high‐temperature catalytic reactions (>600 °C) are still hindered, because of their low stability under harsh reaction conditions. In this work, we have developed a zeolite‐confined bimetallic PtIn catalyst with exceptionally high stability against sintering. A combination of experimental and theoretical studies shows that the isolated framework In(III) species serve as the anchoring sites for Pt species, precluding the migration and sintering of Pt species in the oxidative atmosphere at ≥650 °C. The catalyst comprising subnanometer PtIn clusters exhibits long‐term stability of >1000 h during a cyclic reaction‐regeneration test for ethane dehydrogenation reaction. [ABSTRACT FROM AUTHOR]

Antipathogenic fabrics coated with different types of metallic nanoparticles were developed for the use in healthcare sector. The citrus plant waste was collected and processed to extract the bioactive molecules for the green synthesis of metal particles. Here, the citrus extract was used for a dual purpose, as a bio reductant and also as a bio dispersant (D-limonene). Subsequently, the green synthesis of a highly concentrated and stable colloidal dispersion of Silver nanoparticles (Ag-NPs), Copper nanoparticles (Cu-NPs) and Zinc Oxide (ZnO-NPs) was carried out using the self-assembled respective salts and green extracted reducing agents without using any other hazardous chemicals. Furthermore, the effect of the loaded D-limonene as a dispersant was justified by PDI, Zeta potential, particle size analysis and Dynamic Light Scattering (DLS). The synthesized particles were assessed for their morphology and geometric characteristics by Scanning Electron Microscopy (SEM), revealing the formation of particles with spherical and oval shapes. The justification for the formation of particles was also analyzed by using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. In the next step, the synthesized Ag-NPs, Cu-NPs and ZnO-NPs were applied to cotton fabric and their antipathogenic properties (antibacterial, antiviral, and antifungal) before and after severe washing were characterized. It was observed that the nanoparticles applied fabric at higher concentration (5g) exhibit even covering of fiber surface, average particles sizes between 350 and 470 nm, with excellent antimicrobial activity against Escherichia coli (3.4 ± 0.35 mm) and Staphylococcus aureus (5.5 ± 0.19 mm). The untreated fabric had a log CFU/ml value of 5.43, indicating no antibacterial effectiveness of the control sample. However, the log values of all the treated samples were significantly lower. Moreover, the intensity of concentration of zinc silver and copper particles explains the 88.48 %, 85.01 % and 94.23% antifungal activity respectively. While antiviral activity (84% reduction) was also highest against copper nanoparticles coated fabric. The level of significance against antipathogenic activities among all particles coated samples was analysed by applying the statistical analysis of simple linear regression with paired t test. In addition the comfort parameters (air and water vapor permeability) for developed medicated textiles were also analyzed. [ABSTRACT FROM AUTHOR]

The process of stone formation in the human body remains incompletely understood, which requires clinical and laboratory studies and the formulation of a new endogenous, nanotechnological concept of the mechanism of origin and formation of crystallization centers. Previously, the mechanism of sialolithiasis was considered a congenital disease associated with the pathology of the ducts in the structure of the glands themselves. To date, such morphological changes of congenital nature can be considered from the position of the intrauterine formation of endogenous bacterial infections complicated by the migration of antigenic structures initiating the formation of crystallization centers. The present work is devoted to the study of the morphology and composition of stones obtained as a result of surgical interventions for sialolithiasis. Presumably, nanoparticles of metals and other chemical compounds can be structural components of crystallization centers or incorporated into the conditions of chronic endogenous inflammation and the composition of antigenic structures, in complexes with protein and bacterial components. X-ray microtomography, X-ray fluorescence analysis, scanning transmission electron microscopy and microanalysis, mass spectrometry, and Raman spectroscopy were used to study the pathogenesis of stone formation. Immunoglobulins (Igs) of classes A and G, as well as nanoparticles of metals Pb, Fe, Cr, and Mo, were found in the internal structure of the stones. The complex of antigenic structures was an ovoid calcified layered matrix of polyvid microbial biofilms, with the inclusion of metal nanoparticles and chemical elements, as well as immunoglobulins. The obtained results of clinical and laboratory studies allow us to broaden the view on the pathogenesis of stone formation and suggest that the occurrence of the calcification of antigenic structures may be associated with the formation of IgG4-associated disease. [ABSTRACT FROM AUTHOR]

Lameness is a crucial problem in dairy farming. It worsens the welfare of cattle, reduces the milk yield, and causes economic losses. The etiology of lameness is varied and the cattle's condition may be infectious or non-infectious. The aim of this research was to analyze the biocidal properties of silver (AgNPs), gold (AuNPs), and copper (CuNPs) nanoparticles against bacteria causing lameness in cattle. The isolated pathogens used were Aerococcus viridans, Corynebacterium freneyi, Corynebacterium xerosis, and Trueperella pyogenes. The tested concentrations of nanoparticles were 50, 25, 12.5, 6.25, 3.125, and 1.56 mg/L. The methods used included the isolation of pathogens using standard microbiological procedures and their identification using mass spectrometry, physicochemical analysis, transmission electron microscopy, and cytotoxicity tests. Studies have shown that AgNPs at 3.125 and 1.56 mg/L concentrations, and CuNPs at 25 and 12.5 mg/L concentrations, have strong biocidal properties, while AuNPs have the weakest antimicrobial properties. The very limited number of in vivo studies focusing on lameness prevention in cattle indicate that new solutions need to be developed. However, further studies are necessary to evaluate if nanoparticles (NPs) may, in the future, become components of innovative biocides used to prevent lameness in dairy cattle. [ABSTRACT FROM AUTHOR]

Particle plasmon resonance (PPR), or localized surface plasmon resonance (LSPR), utilizes intrinsic resonance in metal nanoparticles for sensor fabrication. While diffraction grating waveguides monitor bioaffinity adsorption with out-of-plane illumination, integrating them with PPR for biomolecular detection schemes remains underexplored. This study introduces a label-free biosensing platform integrating PPR with a diffraction grating waveguide. Gold nanoparticles are immobilized on a glass slide in contact with a sample, while a UV-assisted embossed diffraction grating is positioned opposite. The setup utilizes diffraction in reflection to detect changes in the environment's refractive index, indicating biomolecular binding at the gold nanoparticle surface. The positional shift of the diffracted beam, measured with varying refractive indices of sucrose solutions, shows a sensitivity of 0.97 mm/RIU at 8 cm from a position-sensitive detector, highlighting enhanced sensitivity due to PPR–diffraction coupling near the gold nanoparticle surface. Furthermore, the sensor achieved a resolution of 3.1 × 10−4 refractive index unit and a detection limit of 4.4 pM for detection of anti-DNP. The sensitivity of the diffracted spot was confirmed using finite element method (FEM) simulations in COMSOL Multiphysics. This study presents a significant advancement in biosensing technology, offering practical solutions for sensitive, rapid, and label-free biomolecule detection. [ABSTRACT FROM AUTHOR]

With the utilization of nitrophenols in manufacturing various materials and the expansion of industry, nitrophenols have emerged as water pollutants that pose significant risks to both humans and the environment. Therefore, it is imperative to convert nitrophenols into aminophenols, which are less toxic. This conversion process is achieved through the use of noble metal nanoparticles, such as gold, silver, copper, and palladium. The primary challenge with noble metal nanoparticles lies in their accumulation and deactivation, leading to a decrease in catalyst activity. Covalent organic frameworks (COFs) are materials characterized by a crystalline structure, good stability, and high porosity with active sites. These properties make them ideal substrates for noble metal nanoparticles, enhancing catalytic activity. This overview explores various articles that focus on the synthesis of catalysts containing noble metal nanoparticles attached to COFs as substrates to reduce nitrophenols to aminophenols. [ABSTRACT FROM AUTHOR]

Surface enhanced fluorescence (SEF) based on noble metal nanoparticles is an effective means to achieve high sensitivity in fluorescence detection. Currently, the physical mechanism behind enhanced fluorescence is not fully understood. This paper measures the fluorescence signals of Dihydroporphyrin f methyl ether (CPD4) under both single-photon and two-photon excitation based on submicrometer silver particles with rough morphologies, achieving enhancement factors of 34 and 45 times, respectively. On this basis, by combining the radiative field characteristics produced by the silver particles, a stimulated radiation model of molecules is established to elucidate the changes in the molecular photophysical process when influenced by silver particles. Moreover, the fluorescence lifetime of the molecules was measured, showing that the presence of silver particles induces an increase in the molecular radiative decay rate, causing the fluorescence lifetime to decay from 3.8 ns to 3 ns. The results indicate that the fluorescence enhancement primarily originates from the submicrometer silver particles' enhancement effect on the excitation light. Additionally, the fluorescence signal emitted by the molecules couples with the silver particles, causing the local surface plasmon resonances generated by the silver particles to also emit light signals of the same frequency. Under the combined effect, the fluorescence of the molecules is significantly enhanced. The findings provide a theoretical foundation for understanding the fluorescence enhancement mechanism of silver particles, adjusting the enhancement effect, and developing enhanced fluorescence detection devices based on submicrometer silver particles, holding significant practical importance. [ABSTRACT FROM AUTHOR]

• Wider variety of artefacts needs to be conserved. • NPs based coating have the potency to replace the traditional coating materials. • The NPs improved the photo-catalysis, hydrophobicity and antibacterial properties. The progression in the use of nanostructured metal oxide or metal oxide based polymeric nanocomposite for the conservation and refurbishment of cultural heritage are presented in this review. Starting from the definition of nanoparticles, their major synthesis techniques, the paper briefly describes the utilization of various metal oxide nanoparticles and metal oxide based polymeric nanocomposite coatings and their surface protection functions including self-cleaning, increased photocatalytic activity, biocidal effects, UV blocking properties and compatibility with the different types of substrates including wood, stones, bricks and paper focussing on their potential usage and their application in the arena of remediation of cultural heritage. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanotechnology is the most innovative field of the twenty-first century. Worldwide, intensive research is being done to commercialize nano products. Due to their unique or improved physical and chemical properties relative to bulk material, nanomaterials, especially nanoparticles have seen an enormous interest over the past few decades. As environmentally benign alternative nanoparticles are currently being produced "biologically" by means of plant or microorganism-mediated synthesis. Due to its outstanding biocompatibility, affordability, and low toxicity, and cost-effectiveness, ZnO NPs have emerged as one of the most widely used metal oxide nanoparticles in various applications. Interestingly, due to its multiple medical, health, environmental, and economic advantages, the green technique of synthesis employing plant materials has been discovered to be suitable for the production of ZnO nanoparticles. A variety of characterization methods have been used to assess the characteristics of ZnO NPs produced with green strategies, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and UV–Vis spectroscopy and others. The value of these techniques reveals important information about the structural, morphological, and optical characteristics of ZnO NPs. In order to support future biomedical and other research, this review provides an overview of recent developments in the green synthesis of ZnO NPs with a focus on natural sources such as plants, bacteria, fungi, and algae as well as their characterizations, and various applications, including, antimicrobial, anticancer, antioxidant, photocatalytic, anti-inflammatory, anti-diabetics, and anti-aging applications. [ABSTRACT FROM AUTHOR]

Materials based on hybrid bimetallic particles with a polyacrylamide shell can act as an efficient centers of energy dissipation in filled composites and reveal more effectiveness than nanoparticles, which, due to their higher surface-to-volume ratio and low interfacial adhesion, can affect the final composite performance. Two types of fillers were obtained as part of polymer-mediated synthesis and subsequent thermolysis and later encapsulated into a LDPE matrix. The metal-polymer complex increases the damping capacity of the hosting material up to 25% at higher concentration. However, the nanoparticles showed a strong increase at 5 wt% (by 20%) and then a sharp decline, which makes metal-polymer particles more suitable for damping purposes. [ABSTRACT FROM AUTHOR]

Global exploration of nanoparticles as nano-fertilizers/nano-fungicides to optimize crop production has attracted greater attention. Among metal oxide nano-formulations, the increasing application and discharge of copper oxide nanoparticles (CuO-NPs) into the environment requires urgent attention due to their toxic and stimulatory impact on plants, including vegetables. This study aimed at the bio-fabrication of CuO-NPs from Rosa indica petal extracts and to assess their nanotoxicity on germination and biological and biochemical growth of tomato plants. The morphological characterization of phytofabricated CuO-NPs by microscopic (SEM/TEM) and spectroscopic (XRD/FTIR) techniques revealed its nanostructure, spherical shape ranging in size between 23 and 47 nm exhibiting different functional groups. Furthermore, tomato-CuO-NPs interactions resulted in reduced germination percentage and plant biomass. At the biochemical level, the chlorophyll content decreased consistently, while malonaldehyde and proline content in tomato foliage enhanced substantially with increasing concentrations of CuO-NPs. Size, lycopene content (71 % reduction), and fruit quality (metabolites like sugars, amino acids, and organic acids) assessed by 1H NMR declined after CuO-NPs exposure in a dose-dependent manner. Further in situ experiments revealed deformation in a stomatal aperture in leaves and accumulation of CuO-NPs in roots, suggesting toxicity under SEM. In summation, this study highlights the toxicity of biosynthesized CuO-NPs to tomato plants paving the way to develop novel strategies to mitigate its toxicity to vegetable crops, particularly tomato under real field conditions. [Display omitted] • Copper oxide nanoparticles (CuO-NPs) exhibit toxic and stimulatory effects on plants. • Biogenic synthesized CuO-NPs from Rosa indica petal extract shows phytotoxicity to tomato plants. • Exposure to CuO-NPs reduces germination percentage, plant biomass, and fruit quality. • Metal oxide nanoparticles increase malondialdehyde and proline content after CuO-NPs exposure. • Strategies need to be developed to counteract nano-CuO toxicity. [ABSTRACT FROM AUTHOR]

Iodide has long been recognized as an effective shape-directing agent for facilitating the growth of anisotropic noble metal nanostructures. However, little attention has been paid to the specific interaction between iodide and metal nanoparticles. In this study, we demonstrate the selective recognition of iodide in solution by the carbon-dot-gold nanoparticles (Cdot-AuNPs) ensemble. Irregularly-shaped AuNPs were generated through the reduction of HAuCl4 by citrate ions and stabilized by Cdot at ambient temperature. Upon the addition of iodide, the color of the solution changed from blue to red with the growth of AuNPs to semi-spherical nanoparticles, as confirmed by transmission electron microscopy. The selectivity test validated that only iodide could induce this specific visual response, highlighting a novel interaction mechanism between iodide and AuNPs. The recognition of iodide by this Cdot-AuNPs ensemble showed good resistance toward many environmentally relevant metal ions, particularly Ca2+, providing potential for the identification of iodide ions in real samples. Mixing tetrachloroauric acid, sodium citrate, and bee pollen-derived carbon dots (Cdot) at ambient temperature leads to the preparation of Cdot-AuNPs ensemble for the specific colorimetric recognition of iodide by reshaping the dimensions of the AuNPs. [ABSTRACT FROM AUTHOR]

The green synthesis of noble metal nanoparticles has gained a lot of interest in the area of nanotechnology, because of its high therapeutic properties. The present study focussed on the synthesis of the silver nanoparticles (Ag-NPs) using Ceropegia debilis leaf extract and characterized by various physio-chemical techniques and surface morphological studies. The prepared Ag-NPs exhibit a face-centred cubic structure, spherical morphology, and high purity as shown by XRD, SEM, and EDS analyses. The average size of the Ag-NPs was confirmed by TEM study as 18.6 ± 7.5 nm. The synthesized Ag-NPs show remarkable antioxidant activity of 72.1% compared to standard BHT 86.9%. Furthermore, Ag-NPs show remarkable cytotoxic properties against MCF 7 and A 549 cell line of 37.19% and 33.33%, respectively at 250 µg/mL. The antibacterial activity of Ag-NPs was investigated against the human pathogen and intestinal pathogen Staphylococcus aureus and Escherichia coli by agar disc diffusion method. Moreover, the synthesised Ag-NPs exhibit good antifungal properties against the fungal specimen Trichoderma viride assessed by well diffusion technique. In addition, Ag-NPs serve as an excellent nanocatalyst in the removal of toxic methylene blue dye (93.2%) from industrial wastewater under sunlight irradiation. [Display omitted] • Silver nanoparticles were synthesized by Ceropegia debilis extract. • SEM and TEM used for surface morphology and size determination. • Impressive anti-proliferative activity towards MCF 7 and A 549 were observed. • Effective nanocatalyst for the degradation of methylene blue dye. [ABSTRACT FROM AUTHOR]

Presently, the creation of metal nanoparticles (NPs) using plant extracts has rapidly gained an appealing aspect in the realm of modern nanobiotechnology, with substantial merits over traditional techniques. In this context, cadmium oxide (CdO) NPs have been created utilizing a bio-inspired green synthetic approach using Citrus limetta peel extract. The active organic biomolecules within the peel extract functioned as reductants and stabilizers for NPs, resulting in pure CdO NPs. The structural, chemical, optical, and topological traits were evaluated utilizing XRD, FTIR, FESEM, EDX, HRTEM, UVDRS, and PL analyses. The synthesized CdO NPs are about 54 nm in size with a quasi-spherical morphology. The computed band gap of NPs was 2.59 eV, which validated the cubic phase formation of CdO NPs. The photocatalytic studies of the as-fabricated CdO NPs were investigated through Rhodamine B (RhB) dye degradation via H2O2-assisted AOP under sunlight. The effect of H2O2, photocatalyst loading, RhB dye concentration, contact time, scavengers, and recyclability study was also investigated in detail to demonstrate the functionality of the photocatalyst. Approximately 85% of the dye was decomposed within 60 min, revealing its excellent photocatalytic performance of CdO NPs. Therefore, the research outcomes thus offer that the CdO NPs may have a substantial potential for ecological remediation through a photocatalytic approach. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) have gained considerable attention for their diverse applications across various fields, including medicine, electronics, and environmental remediation, agriculture and manufacturing. The relationship between metal nanoparticles and the microorganisms, highlighting the diverse mechanisms through which nanotoxicity manifests and influences microbial communities. Metal nanoparticles, owing to their unique physicochemical properties, can interact with the microbiome directly or indirectly, disrupting microbial homeostasis and functionality. The interactions are complex, involving mechanisms such as membrane disorganization, reactive oxygen species (ROS) generation, and oxidative Deoxyribonucleic acid (DNA) damage. Comprehending the different types of metal nanoparticles, their antimicrobial properties, and the mechanisms that underlie their nanotoxicity towards microorganisms is imperative for the secure advancement and implementation of nanotechnology, paving the way for innovative strategies to mitigate adverse effects and promote sustainable nanomaterial applications. Nanotechnology has witnessed remarkable advancements in various fields, yet concerns regarding its potential adverse effects on biological systems, particularly the microbiome, have emerged as a significant area of investigation. This abstract highlight the importance of interdisciplinary approaches encompassing nanoscience, microbiology, and toxicology to unravel the intricate dynamics of metal nanoparticle-microbes' interactions and facilitate the design of safer nanoproducts for diverse applications. Overall, this study emphasizes the need for more investigation to clarify the complex dynamics of metal nanoparticles in microbial environments and their long-term effects on sustainability and environmental health. [ABSTRACT FROM AUTHOR]

Ciprofloxacin (CIPH) was classified as one of the most effective quinolone antibiotics, which is commonly used to cure a wide range of infections resulting from Gram-negative and Gram-positive microorganisms. The complexes which formed due to the interaction of Ni(II), Zn(II), Cu(II), Gd(III) and Sm(III) with ciprofloxacin were characterized by CHN% analysis, conductivity, FTIR, electronic spectra, fluorescence measurements, and magnetic susceptibility, besides studying the complex–DNA interaction. Meanwhile, the molar conductance values (0.001 mol·L−1 in DMSO) revealed the electrolytic behavior of the complexes and could be designated with the A−B+ formula. In addition, the geometry of the compounds was confirmed from the electronic transitions as well as the μeff values as octahedral for all complexes. The postulated formula could be generally assigned as [M(CIP)a(CIPH)b(H2O)c](NO3)(H2O)n(C2H5OH)m. Moreover, the interaction between metal complexes and DNA revealed that the Cu complex had the highest binding constant. Nanotechnology was applied to synthesized compounds using silica nanoparticles (SiNPs), which were prepared using a sol–gel process. The silica nanoparticles were chemically functionalized for binding the ligand and its metal complexes; this enables the as-prepared compounds to enhance their features as a drug delivery platform. Meanwhile, the antimicrobial activity was tested for the free complexes and SiNPs composites. Collectively, Sm complex gave the largest zone of inhibition, while the Cu(II)–SiNPs composite showed the strongest potential to reduce the bacterial activity. Furthermore, the fluorescence data of CIPH, ligand–metal mixture and the effect of silica nanoparticles on them were studied. [ABSTRACT FROM AUTHOR]

Bacteriocins are antimicrobial peptides produced by bacteria to prevent the growth of pathogens. Combining bacteriocins with metal nanoparticles, like silver nanoparticles (AgNPs), has developed into a viable strategy to get over bacteriocin limitations. In this study, bacteriocin BacZY05 was extracted from Bacillus subtilis ZY05 and purified using various techniques. The resulting purified bacteriocin was then combined with silver nanoparticles to form bacteriocin silver nanoconjugates (BacZY05-AgNPs). The physicochemical properties of the BacZY05-AgNPs were characterized using various analytical techniques. The mean diameter of the synthesized AgNPs was approximately 20–60 nm with an oval or spherical shape. The antimicrobial activity of the BacZY05-AgNPs was evaluated against several indicator strains by their zone of inhibition (ZOI), using the agar well diffusion method. Compared to bacteriocin (ZOI- 13 to 20 mm) and AgNPs (ZOI- 10–22 mm) alone, the antibacterial activity data demonstrated a 1.3-1.5-fold increase in the activity of bacteriocin-nanoconjugates (ZOI- 22 to 26 mm). For Staphylococcus aureus MTCC3103 and Klebsiella pneumoniae MTCC109, BacZY05-capped AgNPs exhibited the lowest minimum inhibitory concentration (MIC), measuring 10.93 µg/mL. For Salmonella typhi NCIM2501, the MIC was 28.75 µg/mL. The highest MIC value was 57.5 µg/mL for Escherichia coli DH5α and Vibrio cholerae MTCC3909. With BacZY05-capped AgNPs, the lowest minimum bactericidal concentration (MBC) of 28.75 µg/mL was observed for Staphylococcus aureus MTCC31003. In the cases of Salmonella typhi NCIM2501 and Klebsiella pneumoniae MTCC109 concentration was 57.5 µg/mL. Vibrio cholerae MTCC3909 and Escherichia coli DH5α had the highest MBC values at 115 µg/mL. [ABSTRACT FROM AUTHOR]

Lung cancer remains a major global health problem with high mortality rates. Early diagnosis can significantly improve prognosis. Hence alternative diagnostic platforms facilitating rapid, noninvasive, point-of-care screening are needed. Nanomaterial-assisted electrochemical biosensors present a promising technology. Unique properties of nanomaterials like high electrical conductivity, catalytic activity, and large surface area enhance achieved detection limits and kinetics. Recent works have combined nanomaterials like graphene, metal nanoparticles and conducting polymers with recognition elements like antibodies and aptamers. Considerable progress has focused on improving analytical parameters including sensitivity, linear ranges, reproducibility and response times. Initial embodiments also demonstrate multiplexed detection, microfluidic integration and smartphone connectivity towards viable clinical practice. However considerable efforts on large sample size validation, standardization of testing protocols and viable commercialization pathways integrating regulatory guidelines and reimbursement ecosystem partnerships remain before such lab-on-chip platforms can enter mainstream and guide therapeutic interventions through affordable decentralized personalized monitoring. [ABSTRACT FROM AUTHOR]

Purpose: The treatment of amoebic infections is often problematic, largely due to delayed diagnosis, amoebae transformation into resistant cyst form, and lack of availability of effective chemotherapeutic agents. Herein, we determined anti-Acanthamoeba castellanii properties of three metal oxide nanoparticles (TiO2, ZrO2, and Al2O3). Methods: Amoebicidal assays were performed to determine whether metal oxide nanoparticles inhibit amoebae viability. Encystation assays were performed to test whether metal oxide nanoparticles inhibit cyst formation. By measuring lactate dehydrogenase release, cytotoxicity assays were performed to determine human cell damage. Hoechst 33342/PI staining was performed to determine programmed cell death (apoptosis) and necrosis in A. castellanii. Results: TiO2-NPs significantly inhibited amoebae viability as observed through amoebicidal assays, as well as inhibited their phenotypic transformation as evident using encystation assays, and showed limited human cell damage as observed by measuring lactate dehydrogenase assays. Furthermore, TiO2-NPs altered parasite membranes and resulted in necrotic cell death as determined using double staining cell death assays with Hoechst33342/Propidium iodide (PI) observed through chromatin condensation. These findings suggest that TiO2-NPs offers a potential viable avenue in the rationale development of therapeutic interventions against Acanthamoeba infections. [ABSTRACT FROM AUTHOR]

Solid oxide electrolysis cells (SOECs), displaying high current density and energy efficiency, have been proven to be an effective technique to electrochemically reduce CO2 into CO. However, the insufficiency of cathode activity and stability is a tricky problem to be addressed for SOECs. Hence, it is urgent to develop suitable cathode materials with excellent catalytic activity and stability for further practical application of SOECs. Herein, a reduced perovskite oxide, Pr0.35Sr0.6Fe0.7Cu0.2Mo0.1O3‐δ (PSFCM0.35), is developed as SOECs cathode to electrolyze CO2. After reduction in 10% H2/Ar, Cu and Fe nanoparticles are exsolved from the PSFCM0.35 lattice, resulting in a phase transformation from cubic perovskite to Ruddlesden–Popper (RP) perovskite with more oxygen vacancies. The exsolved metal nanoparticles are tightly attached to the perovskite substrate and afford more active sites to accelerate CO2 adsorption and dissociation on the cathode surface. The significantly strengthened CO2 adsorption capacity obtained after reduction is demonstrated by in situ Fourier transform‐infrared (FT‐IR) spectra. Symmetric cells with the reduced PSFCM0.35 (R‐PSFCM0.35) electrode exhibit a low polarization resistance of 0.43 Ω cm2 at 850 °C. Single electrolysis cells with the R‐PSFCM0.35 cathode display an outstanding current density of 2947 mA cm−2 at 850 °C and 1.6 V. In addition, the catalytic stability of the R‐PSFCM0.35 cathode is also proved by operating at 800 °C with an applied constant current density of 600 mA cm−2 for 100 h. [ABSTRACT FROM AUTHOR]

The low signal-to-noise ratio (S/N) and single functionality of fluorescence imaging agents have limited their practical applications. Bright two-photon excitation (2PE) imaging probes are highly desirable in vivo with larger imaging depth, minor autofluorescence background, and less photodamage. Herein, we developed responsive aggregated gold nanoparticles (Au NPs) as high contrast 2PE imaging agents, capable of emitting red fluorescence upon excitation of near-infrared (NIR) laser and possessing a high signal-to-noise ratio (S/N of 2,475). By forming aggregates in situ inside tumor tissue, doxorubicin hydrochloride (DOX)-loaded mix-charged gold nanoparticles (DOX-MC-Au NPs) were utilized to act as selective fluorescence imaging probes and precise therapy agents. These high-contrast theranostic agents offer a promising potential for precise cancer imaging and therapy, which might open a new venue to multifunctional and noninvasive theranostics. [ABSTRACT FROM AUTHOR]