Next Nanotechnology最新文献

Metal nanoparticles have a noteworthy future in cancer treatment research because of their smaller size and large active surface area. Though gold, silver, platinum, palladium, copper, zinc, iron and several other metal nanoparticles have been explored for their anticancer potential in different pathways, the main limitation of these particles is their toxicity which may be controlled through their size, surface modification and route of administration. Compared to other metal nanoparticles, ruthenium nanoparticles have high bio compatibility and they exhibit excellent photo-thermal effect. Though there are several reports in the literature on the anticancer potential of ruthenium complexes, ruthenium nanoparticles are not much investigated. In the present work, therefore, an attempt has been made to synthesize ruthenium nanoparticles in an easy and eco-friendly way using Aloe vera gel. Ruthenium chloride was used as a precursor and Aloe vera gel acted both as reducing and capping agent. The synthesized ruthenium nanoparticles were characterized using UV-Visible spectrophotometry, Fourier Transform Infrared Spectroscopy (FT-IR), High Resolution Transmission Electron Microscopy (HRTEM), Powder X-ray Diffraction (PXRD), Dynamic Light Scattering (DLS) and Field Emission Scanning Electron Microscopy (FESEM). The analyses confirmed the formation of nano globules of Aloe vera gel of diameter in the range 90–300 nm with ruthenium nanoparticles of average size 1.5 nm embedded in them. The synthesized Ru nanoparticles embedded in the nano globules of Aloe vera gel (ALV RuNPs) were explored for their anticancer potential in the Dalton's lymphoma ascites (DL) cell line using Trypan Blue assay. The results of the assay showed that the ALV RuNPs can induce concentration dependent cytotoxicity in DL cancer cells. Approximately 40 % cytotoxicity was obtained for concentration range 5–50 mg/mL of the sample while negligible cytotoxicity was observed for healthy PBMC cells. Theoretical study indicates significant interaction between the components present in Aloe vera and Ru-nanoparticles. The results showed that ruthenium nanoparticles can emerge as a promising bio-compatible candidate with the ability to selectively target cancer cells while sparing normal cells.

The growing interest in the utilization of natural plant-derived products, particularly essential oils as eco-friendly agrochemicals has spurred the consumer demand for clean-label products. Due to their robust antimicrobial and pesticidal properties, essential oils (EOs) exhibit significant potential in food preservation and agricultural applications. However, the poor aqueous stability and highly volatile nature of EOs limit their potential for practical applications in their pure form. In response, nanoemulsions (NEms) have emerged as promising delivery vehicles for EOs, offering advantages such as smaller size, high solubilization capacity, excellent encapsulation efficiency, and controlled release characteristics.

Here we review the recent advancements in the fabrication, optimization, and stability of EO NEms. The present article provides an in-depth exploration of all the currently available high-energy (ultrasonication, micro fluidization, high-pressure homogenization, rotor-stator mixer) and low-energy (spontaneous emulsification, phase inversion composition, emulsion inversion point, phase inversion temperature) methods being used for the fabrication of NEms and the respective advantages and disadvantages associated with them. Additionally, the review discusses various destabilization mechanisms such as Ostwald ripening, coalescence, etc. that generally impact essential oil NEms, providing a comprehensive understanding of the challenges associated with their stability. Furthermore, the review focuses on the recent practical applications of NEms in the sector of food preservation, flavoring agents, and sustainable agricultural practices.

Sensible thermal storage ceramics in the form of the fluid-bed show good competency on dealing with the intermittency of renewable energy and improving energy utilization efficiency by integration the functions of thermal absorption and storage. In-situ nano-sized β-Sialon whiskers reinforced Al₂O₃-based ceramic materials for fluid-bed thermal storage system were one-step synthesized by aluminothermic reduction method, using solid waste coal-series kaolin and Al powder as main raw materials and firing at 1500 °C in N₂ atmosphere. The effects of Al content and firing temperature on phase evolution, microstructure and properties of fired samples were researched by XRD, SEM, TEM, etc. The results showed that nano-sized β-Sialon whiskers could be in-situ synthesized at 1300 °C, which effectively enhanced the bending strength of fired samples. The highest β-Sialon content and the optimal properties could be achieved at 1500 °C while coal-series kaolin and Al mass ratio was equal to 70∶30, which were listed as follows: 30.7 % β-Sialon content, 74.9 MPa high-temperature bending strength (at 1400 °C), 6.17 × 10^-6·°C^-1 thermal expansion coefficient (room temperature-1000 °C), 0.74 J·(g·K)^-1 specific heat capacity (at room temperature), 873.90 kJ·kg^-1 theoretical thermal storage density (ΔT=900 °C), which is suitable as the thermal storage material for the fluid-bed thermal storage system.

Copper oxide nanoparticles (CuO NPs) have been prepared via sol-gel synthetic approach using aqueous leaves extract of Musa paradisiacal and copper chloride dehydrate salt. UV visible spectroscopy showed maximum peak for CuO NPs at 535 nm. Additionally, the SEM XRD techniques confirmed spherical shape of CuO NPs with average size of 15 nm. Nitro compounds have been carefully chosen as a tested contaminant to study performance of CuO NPs. Catalytic reduction of nitro compounds was investigated under different temperatures to evaluate thermodynamic studies. According to the results, catalytic reduction of nitro compounds obeys Langmuir–Hinshelwood mechanism. The value of apparent rate constant shows a linear trend with catalyst concentration. The catalytic pyrolysis of corncob biomass in the presence of CuO NPs showed more bio-oil (46.13 %) yield as compared to ZSM-5 (40.07 %) and without catalyst (37.09 %) reactions. The data also confirmed that CuO NPs showed excellent performance as a micro-reactor for catalytic degradation of nitro compounds and catalytic pyrolysis. The CuO NPs have been isolated and reused in 5 consecutive cycles with good and reproducible excellent performance.

All-inorganic cesium lead bromide (CsPbBr₃) quantum dots (QDs) have received a surge of attention in the field of light-emitting diode (LED) display and lighting. Hence, it is interesting to study the composite film composed of CsPbBr₃ and light-emitting MDMO-PPV matrix polymer. In this study, we investigate the phase behavior among the components, MDMO-PPV, toluene (solvent), and oleic acid and oleylamine (the surface ligands for QDs) based on the Flory-Huggins theory with the group contribution method for the first time. Here we find that the MDMO-PPV and ligand molecules are immiscible whereas MDMO-PPV and toluene are partially miscible. Then through the x-ray diffraction (XRD) patterns, we demonstrate that CsPbBr₃ QDs form a nanoscale domain with ∼33–52 nm crystallites in the MDMO-PPV matrix. Furthermore, the scanning electron microscope (SEM) images display that CsPbBr₃ QDs can be highly aggregated at MDMO-PPV:CsPbBr₃= 50:50 composition. Then, through the ultraviolet-visible (UV–vis) and photoluminescence (PL) spectra, the enhancement of PL intensity is observed at ∼30–50 wt% CsPbBr₃. Finally, the electrochemical impedance spectra indicate that the composite film exhibits less resistance (∼3.2×10⁴ Ω) than the pure MDMO-PPV film (∼1.4×10⁷ Ω), suggesting that the MDMO-PPVCsPbBr₃ composite approach is promising for electrochemical and optoelectronic applications.

Highly porous and nanostructured metal-organic frameworks (MOFs) have fascinated enormous interest as electrode active materials for electrochemical energy storage systems, whereas their practical applications are significantly hindered by their relative inferior energy density and cyclability. In this study, MoS₂ with layered structure was successfully incorporated onto hierarchical Ni-MOFs via a facile hydrothermal approach. Moreover, sodium cations were introduced to improve electronic conductivity. The resulting nanocomposites (sodium ions and MoS₂ incorporated Ni-MOFs) exhibited hierarchical porous structures with varying dimensions, offering increased volume for charge storage and diffusion channels for electrolyte ions. Benefiting from the unique topological architectures, the as-synthesized porous nanocomposites delivered an excellent supercapacitive performance, achieving a superlative energy of 33.33 Wh kg⁻¹ and a power density of 3390 W kg⁻¹. Furthermore, the as-fabricated symmetric supercapacitor device delivered a remarkable cycling durability where the acquired outstanding capacitance retention was 97.42% and coulombic efficiency was 97.82% respectively over more than 10,000 cycles in an aqueous electrolyte.

Chloride and fluoride are very reactive water contaminants that have adverse effects on animal health as well as their psychochemical processes. The sensing of these two anions in an aqueous medium is important for clinical diagnosis, environmental monitoring, and various industrial applications. In this report, the stable colloid of gold nanoparticles functionalized (AuNPs) with 2-quinonimine (2-QI) was successfully synthesized to be used in the colorimetric sensing application of chloride and fluoride ions in an aqueous medium. A decrease in intensity of the Surface Plasmon Absorption (SPR) band in UV–VIS spectra was observed for colloids of AuNPs functionalized with 2-QI upon a gradual increase in the concentration of chloride or fluoride ions with respect to the water dilution. Though the intensity of the SPR band was found to decrease in the pH range of 2–12, the best result was observed at pH 2. A linearity range was observed up to 0.04 mM concentration of both the analyte for 880 μM AuNPs with sensitivity of ∼18–20 mM⁻¹ and a limit of detection of ∼8–8.5 μM. An immediate selective decolorization was observed by the naked eye for 0.5 mL of 160 μM AuNPs in a 0.5 mL aqueous chloride solution of 15 mM and fluoride solution of 17.5 mM. The responses were found to be selective over the other common cations, anions, or biomolecules tested. The proposed sensing mechanism was explained as the accumulation of AuNPs in micro-particles by destroying the stabilization of AuNPs through dipolar interaction with 2-QI.

A series of wide-ranging single phase YPO₄:xTb³⁺ phosphor was prepared by wet chemical route. In order to maximise the use of YPO₄:Tb³⁺ nanoparticles in WLED, this work used Li⁺ sensitization to interstitially modify the particles' photoluminescence intensity. The prepared nanoparticles are characterized using X-Ray diffraction, FT-IR, TEM and Photoluminescence. The annealing effect on the particle size, morphology and its luminescence intensities are studied. This increased crystallinity led to a rise in the photoluminescence intensity of the nanoparticles. YPO₄:Tb³⁺ nanoparticles' excitation and emission spectra were shown by photoluminescence investigations. Optical absorption and emission spectra confirmed all peaks associated to various transitions of the Tb³⁺ ions. Because of the increased crystallinity and decreased water content, the emission intensity rose with the annealing temperature. Li⁺ co-doping increased the emission intensity even more; where the emission intensity showed seven times. The results emphasise the significance of Li⁺ sensitization and annealing temperature in adjusting the luminous properties for possible uses in WLED and other display systems

Flexible sensors play an important role in simulation, brain-computer interaction, intelligent robots, and biological detection. Due to the progress of modern medical means, the construction of wearable flexible sensors to realize remote and continuous monitoring of human physical indicators and physiological parameters has become a hot research topic. Non-invasive sensor is a device that can detect physiological parameters without cutting the skin or puncturing the body. They have wide application prospects in the fields of medical treatment, fitness, and daily care due to the following advantages: real-time monitoring, portability, accuracy, and cost reduction. Liquid metal has become a great candidate for constructing flexible biosensors because of its high conductivity, deformability, self-healing, and bio-friendly properties, its spontaneous formation of an oxide film due to exposure to oxygen provides a convenient reaction platform for the preparation of other materials. Two-dimensional materials are inherently superior in preparing sensors due to their great advantages unique chemical and physical properties, their high surface area-to-volume ratios and ultra-high surface sensitivity to the environment also can be used to prepare flexible sensor. This study presents an overview and introduction of biosensors fabricated by liquid metal and two-dimensional materials, including how to prepare specific two-dimensional materials based on liquid metal, and the stripping method is also included. Three kinds of applications are discussed in detail, including the detection of human glucose concentration, pulse detection, and sweat analysis, whose sensing principles depend on piezoelectric, optical, and electrochemical. At the end of the article, we summarized the current challenges faced by biosensors based on liquid metal and looked forward to its future development and future directions of advances.