Journal of Nanoparticle Research最新文献

In recent years, the use of biomolecules as dispersants for the preparation of 2D nanomaterials by direct liquid-phase exfoliation (LPE) using ultrasonication has attracted increasing attention as a convenient and cost-effective approach to ensure simultaneously the biocompatibility of these nanostructures. In this work, we prepare MoS₂ quantum dots (QDs) by the LPE method using deoxyadenosine monophosphate (dAMP) as an exfoliation agent that provides a good biocompatibility of the QDs too. As a result, a visible-range photoluminescence from MoS₂ QDs surrounded by nucleotides is observed for the first time. Different structures of MoS₂ QDs with dAMP are analyzed employing the DFT calculations. It is shown that dAMP can form coordination bonds with the Mo atoms located at the QD edges or at the defect sites where direct contacts with these atoms can occur. The covalent bonds facilitate strong adsorption of dAMP on a MoS₂ QD. The structural flexibility of the nucleotide adsorbed on the MoS₂ QD enables a combination of noncovalent stacking interaction of the nucleobase and a coordination bond of the phosphate group with the Mo atoms located at the edges to occur. This leads to the formation of a very energetically stable complex.

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Nanotechnology has transformative potential in agriculture by optimizing plant nutrient use. In this study, zinc oxide nanoparticles (ZnO-NPs) were synthesized using ZnSO4.7H2O as a precursor. The synthesized ZnO-NPs exhibited a particle size of 63.60 nm, stability characterized by a zeta potential, and a semispherical agglomerated shape under scanning electron microscopy (SEM). The purity of the nanomaterials was confirmed through energy-dispersive X-ray spectroscopy (EDAX). SEM-EDAX analysis of groundnut seeds primed with ZnO-NPs showed improved zinc adsorption and distribution compared to bulk ZnSO4, with no physical damage, indicating good biocompatibility. The small size and high surface area of the nanoparticles enhanced zinc uptake, as confirmed by higher zinc levels in ZnO-NP-treated seeds. ZnO-NP priming resulted in greater physio-biochemical responses, enhancing germination and the seedling vigor index at 10 days post-sowing. Biochemical analysis revealed elevated levels of chlorophyll, soluble protein, total soluble sugar, and free amino acid in the leaves of ZnO-NP-treated plants. Furthermore, ZnO-NP-treated groundnut seedlings exhibited significantly greater DPPH radical scavenging activity than control plants, indicating enhanced antioxidant potential. This study further explored the elevations in the levels of antioxidant enzymes (superoxide dismutase-SOD, catalase-CAT, ascorbate peroxidase-APX, guaiacol peroxidase-GPX and polyphenol oxidase-PPO) primed with ZnO-NPs to augment the hydration of seeds, increase antioxidant enzyme activity to neutralize reactive oxygen species, preserve cellular integrity, and promote overall plant health. These findings underscore the potential of ZnO-NPs as a sustainable nanotechnological approach for enhancing groundnut seed germination, seedling vigor, and stress tolerance, ultimately promoting crop growth and productivity.

In this study, our research was focused on the synthesis and characterizing of novel mixed metal–metal organic frameworks (MM-MOFs) incorporating porphyrin ligands. Furthermore, we investigated their performance in photodegrading 1,5-dihydroxynaphthalene (1,5-DHN) into 5-hydroxy-1,4-naphthalenedione (Juglone). Integrating metalloporphyrin-based ligands into bimetallic MOFs represents a pioneering advancement in this field. Photocatalytic reactions were conducted using various stoichiometric ratios of Co and Zn as metal nodes, along with meso-tetra(4-carboxyphenyl)porphyrin (TCPP-H₂) and Mn(III) meso-tetra(4-carboxyphenyl)porphyrin chloride (Mn-TCPP) as linkers. Results revealed that Co as a node led to the formation of nanorod metal–organic frameworks (MOF) structures, while Zn enhanced photocatalytic activity. Significantly, a photodegradation yield of 72% was achieved with a 1:3 molar ratio of Co to Zn in Zn_75%/Co₂₅ (TCPP-Mn), demonstrating a synergistic interplay between Co to Zn nodes and Mn-porphyrin linkers. Characterization was performed using structural and microscopic methods. Additionally, various parameters were optimized to elucidate the photocatalytic mechanism, revealing the promising potential of MM-MOFs for efficient photodegradation of 1,5-DHN and beyond. It is noteworthy that the integration of metalloporphyrin-based structures into MM-MOFs for photodegradation processes is relatively uncommon, underscoring the novelty and potential significance of incorporating porphyrin-based ligands in mixed metal MOFs for photodegradation applications.

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The increasing production of zinc oxide nanoparticles and their use in products of sanitary interest make the analysis and characterization extremely important from the point of view of public health and environmental risk. This work aimed to validate the methodology using SP-ICP-MS to measure and quantify nanoparticles of ZnONPs and dissolved zinc—Zn(i). This study pointed out that the method was suitable for the purpose, presenting satisfactory results for the recovery and precision test for Zn(i) and size of NPs. The limits of detection size, dissolved zinc concentration, and particle concentration were 67 nm, 0.4 µg L⁻¹, and 1.08 × 10⁵ particles mL⁻¹, respectively. Thus, the results obtained demonstrate that the technique can be used to determine the size and concentration of Zn(i) in different products.

Iron (Fe)-incorporated zinc oxide (ZnO) nanoparticles (NPs) were synthesized via chemical precipitation technique and studied using powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FESEM), and UV–vis diffuse reflectance spectroscopy. PXRD analysis reveals a hexagonal wurtzite structure for all the synthesized samples. UV–visible measurements demonstrate a reduction in the bandgap of ZnO with an increase in Fe concentration. The ZnO and Fe-incorporated ZnO NPs are studied for the degradation of organic textile dye under visible light irradiation. All the nanoparticles are thoroughly investigated using impedance and dielectric measurements in the frequency range of 20 Hz to 1 MHz. The results obtained are compared, interpreted, and presented in this paper.

The synthesis of water-soluble nanoparticles is a well-developed field for ferrite-based nanoparticles with the majority consisting of iron oxide or mixed metal iron oxide nanoparticles. However, the synthesis of non-agglomerated non-ferrite metal or metal oxide NPs is not as well established. The synthesis and characterization of uniform 20 nm, water-soluble cobalt oxide (CoO) nanoparticles (NPs) is described. These nanoparticles have two principle components: (1) a CoO core of suitable size to contain enough cobalt atoms to be visualized by X-ray fluorescence microscopy (XFM) and (2) a robust coating that inhibits NP aggregation as well as renders them water-soluble. Stable cobalt oxide NPs are initially obtained with octadecyl amine coatings as reported by Bhattacharjee. Two strategies for solubilizing these NPs in water were investigated with varying degrees of success. Exchanging the octadecyl amine coating for a nitrodopamine anchored PEG coating yielded the desired water-soluble NPs but in very low yield. Alternately, leaving the octadecyl amine coating on the NPs and interdigitating this with a maleic anhydride-vinyl copolymer with different hydrophobic sidechains followed by opening the maleic anhydride ring with amine substituted PEG polymers (the water solubilizing component), yielded the desired water-soluble NPs in good yield. Characterization data for the nanoparticles and the components of the coatings required for bioorthogonal reactions to ligate them with biotargeting agents are also described.

In the presented work, a new original procedure for the interfacial synthesis of the magnetic nanoparticles (MNPs) modified with a polymer shell and functionalized by an ionic liquid or a deep eutectic solvent in aqueous biphasic systems (ABSs) is proposed. The synthesis is carried out at the interface of immiscible liquids based on aqueous solutions of polyethylene glycol and inorganic salts. The advantages of the ABSs are biocompatibility, availability, and the high solvating properties of the components, which leads to control the composition and size of the prepared MNPs. The synthesis of the Fe₃O₄@PEG, Fe₃O₄@PEG@Cyphos IL 101, and Fe₃O₄@PEG@TOPO/butanol MNPs has been provided for biomedical and analytical applications. The morphology and structure of MNPs have been characterized by scanning and transmission electron microscopy, thermogravimetry, X-ray diffraction, and FT-IR spectroscopy. The average diameter of the MNPs is 12–14 nm with a narrow size distribution. Their superparamagnetic nature has been described using magnetometry. The synthesis parameters have been optimized and statistically analyzed using response surface methodology. The developed approach of interfacial synthesis can be potentially scaled up and/or be used to obtain nanoparticles of various composition and application.

The influence of electric fields on the magnetic susceptibility of magnetic colloids of different types was investigated. Dependences of the dynamic magnetic susceptibility of a kerosene-based homogeneous magnetic colloid on the intensity of the applied constant electric field were studied. Some features of such dependences were found at the additional impact of a constant magnetic field. The magnetic susceptibility of a magnetic colloid with a well-developed system of microsized droplet aggregates was also investigated under the action of a constant electric field as well as of an alternating electric field. Moreover, similar studies were carried out for a magnetic emulsion produced by emulsifying a kerosene-in-oil-based magnetic colloid. The peculiarities of the susceptibility of the considered systems were determined by structural changes which were observed and analyzed by optical microscopy. The results obtained were validated, and qualitative agreement between the experimentally obtained dependences and those calculated theoretically based on the models used was shown.

We have carried out a systematic investigation on the impact of Fe₃O₄ nanoparticles (NPs) and Rhizobium inoculation on nodulation and growth of common bean plants (cv. Red Guama, Phaseolus vulgaris). Three distinct treatments were conducted on the common bean plants: (i) exposure to Fe₃O₄ NPs; (ii) Rhizobium inoculation; and (iii) a combined treatment involving Fe₃O₄ NPs + Rhizobium inoculation, with non-treated plants as controls. Temperature and magnetic field dependence of magnetization, M(T, H), measurements were performed on both the soil, and dried organs of the plants including roots, nodules, stems, and leaves. M(T, H) analyses indicated a systematic increase in magnetization across organs of plants treated with Fe₃O₄ NPs and combined Fe₃O₄ NPs + Rhizobium. We have found the magnetic contribution, generally related to Fe content in the soil and plant organs, significantly increased in plants exposed to Fe₃O₄ NPs, further indicating absorption, translocation, and accumulation of Fe₃O₄ NPs in the areal parts of the plants. Plants treated with Fe₃O₄ NPs and combined Fe₃O₄ NPs + Rhizobium exhibited Fe₃O₄ NPs accumulation in all organs with increasing concentrations of 69.7 to 74.1 N_NPs/g in roots, 5.6 to 7.7 N_NPs/g in stems, and 3.1 to 5.5 N_NPs/g in leaves, respectively. The iron concentration in nodules was found to be close to 65 N_NPs/g. No appreciable difference in the absorption index AI of roots between plants treated with Fe₃O₄ NPs (~ 1.73%) and Fe₃O₄ NPs + Rhizobium (~ 1.79%) has been observed. The translocation index TI increased by ~ 46% in plants treated with Fe₃O₄ NPs + Rhizobium (6.9%) compared to Fe₃O₄ NPs (4.3%). Treated plants showed improved symbiotic performance including nodule leghaemoglobin and iron content, number of active nodules per plant, and nodule dry weight. The best result was obtained using the combined treatment of Fe₃O₄ NPs + Rhizobium. This study provides evidence that M(T,H) measurements constitute a valuable tool in monitoring the uptake, translocation, and accumulation of Fe₃O₄ NPs in plant organs of common bean plants.