Journal of Nanoparticle Research最新文献

A highly sensitive and stable electrochemical sensor was developed by modifying a pencil graphite electrode (PGE) with nitrogen-doped carbon dots and gold nanoparticles (AuNPs@N-CDs). This hybrid-modified electrode exhibited significantly enhanced electrochemical performance for detecting ciprofloxacin (CIP) compared to the bare PGE and electrodes modified with either N-CDs or AuNPs alone. The morphology and structural properties of the AuNPs@N-CDs/PGE were comprehensively analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX). Electrochemical methods, including cyclic voltammetry (CV) and differential pulse voltammetry (DPV), were used to investigate the electrode modification process, assess CIP concentration, and examine potential interference effects. The sensor demonstrated a broad linear detection range from 5.0 × 10⁻¹⁰ to 3.0 × 10⁻⁸ M, with a detection limit reaching 4.3 × 10⁻¹¹ M. Moreover, the sensor was effectively utilized for the quantitative analysis of CIP in real-world samples such as human serum, urine, and pharmaceutical tablets, confirming its suitability for trace-level detection in real sample.

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High-quality silica core and gold shell spherical nanoparticles were synthesized with precise control over their dimensions and well-defined plasmonic resonances. We demonstrate that the simultaneous synthesis and adsorption of small gold seeds onto functionalized SiO₂ spheres, combined with a suitable reducing agent and optimized reaction conditions, are crucial for the growth and coalescence of the gold seeds into uniform and closed layers. This improvement enables the production of core–shell nanostructures whose extinction spectra exhibit excellent agreement with predictions from Mie theory.

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We present a comprehensive density functional theory (DFT) study of Mo-doped silver clusters Ag(_n)Mo (n = 1–14), focusing on their structural, electronic, and bonding properties. Global optimization reveals an evolution from planar and low-symmetry isomers in small clusters to compact three-dimensional geometries with higher symmetry, culminating in a highly stable icosahedral structure at (n=12). Binding energy and second-order energy difference analyses identify (n=12) as a “magic number” cluster exhibiting enhanced thermodynamic stability and a pronounced HOMO–LUMO gap, indicative of electronic shell closure. Bond length analysis shows relatively constant Ag–Mo distances alongside a size-dependent increase in Ag–Ag bond lengths, reflecting the growth of metallic bonding networks. Hirshfeld charge analysis reveals significant charge transfer from Ag to Mo in small clusters, which decreases with size as the system transitions toward delocalized metallic bonding. These findings provide detailed insights into the size-dependent interplay of geometry, bonding, and electronic structure in Ag(_n)Mo clusters, with implications for their catalytic and material applications.

This work reports the development of a 3D-printable photopolymerizable nanocomposite containing upconversion nanoparticles for in situ UV generation and a Proof of Concept (PoC) with the aim of establishing, as a parameter, photopolymerization monitored by ATR-FTIR spectroscopy to assess the potential possibility of IR-activated decontamination of 3D printed surfaces. This PoC is based on the equivalence between the UV dose values required for photopolymerization and the dose value required for viral inactivation, as reported in the literature. The process involved (1) the synthesis and characterization of NaGdF₄:Yb³⁺:Tm³⁺ upconversion nanoparticles (UCNPs) as the optically active phase and (2) the incorporation of these nanoparticles into a photopolymerizable resin. The resulting upconversion photopolymerizable nanocomposite (UCPPNC) was 3D-printed via masked stereolithography (MSLA) and exhibited UV emission under 980 nm near-infrared (NIR) excitation through a five-photon upconversion mechanism. Real-time ATR-FTIR spectroscopy of samples under 980 nm pumping showed that the UV radiation produced in situ by the incorporated UCNPs was sufficient to enable photopolymerization of the surrounding resin. Thus, the PoC demonstrated, through an indirect but relevant correlation, the potential of UCPPNCs as an IR-activated decontaminable printable material. This nanoparticle-enabled material may offer a safer and more energy-efficient alternative to conventional UV disinfection methods, enabling spatially controlled inactivation of pathogens, while its compatibility with additive manufacturing supports rapid prototyping of customized and application-specific designs for healthcare, public infrastructure, and wearable technologies. Finally, the proposed PoC allowed us to pre-evaluate the material’s potential for IR-activated decontamination, establishing a biological testing-free process for preliminary analysis.

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To handle the ill-posed inverse problem in the measurement of particle size distribution (PSD) of polydisperse particle system using dynamic light scattering (DLS), a hybrid method named as CONTINfit-GRNN is proposed in this paper. The CONTINfit-GRNN is constructed by taking advantages of the constrained regularization method (CONTIN), the nonlinear least squares fitting strategy and a general regression neural network (GRNN). Simulation data for the electric field autocorrelation function (ACF) and fitted data for CONTIN are used to generate the training set, and the optimal smoothing parameter, which adjusts the generalization ability of GRNN, is determined by minimizing the deviation of the distribution. To validate the capability of this method, CONTINfit-GRNN is used to estimate both the unimodal and bimodal PSDs. Simulation results show that CONTINfit-GRNN achieves higher accuracy than fitting data of CONTIN in both narrow and broad distributions, and also shows high stability in the inversion of PSD as the noise level increases.

This manuscript presents a comprehensive study of the magnetic and thermal properties of iron boride (Fe₂B) nanoparticles (NPs), which were synthesized using an arc melting method followed by ball milling. These NPs possess significant promise for use in self-regulating magnetic hyperthermia. The ball-milling method played a crucial role in decreasing the crystallite size, thereby modulating the fundamental magnetic properties, such as coercivity and saturation magnetization (({M}_{s})), both of which are strongly size-dependent. The measured Curie temperatures (({T}_{C})) of the nanoparticles were within the range of 315 K to 320 K ideal for therapeutic hyperthermia applications- making it possible to utilize such materials in the field of hyperthermia and cancer treatment. The specific absorption rate (SAR) peaked at 10.2 W/g for Fe₂B NPs, having an average crystallite size of approximately 14 nm, indicating that these nanoparticles exhibit enhanced thermal performance compared to most standard magnetic nanomaterials. The biocompatibility of Fe₂B NPs was confirmed through hemolysis tests, along with WST-8 colorimetric method-based assays. These nanoparticles were encapsulated in liposomes, which further decrease their toxicity. This renders Fe₂B nanoparticles more compatible with the body and more promising for future medical applications, such as magnetic hyperthermia.

The possibility of using magnetite nanoparticles as a sorbent in the isolation of nucleic acids from cells was investigated in this study. Nanoparticles were synthesized by polyol method in ethylene glycol with addition of polyethylene glycol. Then, the nanoparticles were coated with silicon oxide by Stöber method. Particles characterization was performed by transmission electron microscopy, infrared spectroscopy, vibrational magnetometry, and ferromagnetic resonance. The study of the IR spectra showed the presence of bands characteristic of polyethylene glycol related to hydroxide and ether groups. The magnetization curves in the region of approaching magnetization to saturation were investigated and the saturation magnetization, magnetic anisotropy constant, and average size of nanoparticles were determined. The fitting of the temperature dependences of the linewidth and resonance field of the ferromagnetic resonance also allowed us to determine the magnetic characteristics of the nanoparticles. Three different methods used to determine the anisotropy constant (from the line width and resonance field of the ferromagnetic resonance and from the field dependence of the magnetization) showed good agreement with each other. The determined anisotropy constant was approximately 1–2·10⁵ erg/cm³, which is close to the anisotropy constant of bulk magnetite. It is shown that 0.5 mg of the developed particles allows obtaining 2.88 (2.67–3.08) μg μg of nucleic acids. Gel electrophoresis has demonstrated a high degree of purity and integrity of the isolated molecules. The results of evaluating the expression of the ACTB and GAPDH housekeeping genes using particle-isolated RNAs were similar to those using a commercial nucleic acid isolation kit.

Multiple cycles of transarterial embolization chemotherapy for hepatocellular carcinoma (HCC) can easily cause the overexpression of P-glycoprotein (P-gp), leading to multidrug resistance (MDR) of HCC. Herein, we linked PLA (polylactic acid) with doxorubicin (DOX) through acid-sensitive hydrazone bonds to prepare PLA-ADH/DOX. Then, PLA-ADH/DOX and disulfiram (DSF) were physically encapsulated into PLGA-PEG (polylactic-co-glycolic acid-polyethylene glycol) as the backbone to fabricate a drug delivery system (DOX/DSF NPs) by nanoprecipitation and emulsion solvent evaporation method. The data of physicochemical characterization showed that DOX/DSF NPs enabled excellent stability at room temperature and pH sensitivity in an acidic environment. More importantly, DOX/DSF NPs could avoid P-gp-mediated efflux through endocytosis pathways and inhibit the function of P-gp by DSF, which increases cellular uptake of DOX in HepG2/DOX cells (hepatocellular DOX-resistant cancer cell line) and promotes DOX to enter the nucleus of HepG2/DOX cells for exerting the therapeutic effect in vitro. In addition, DOX/DSF NPs could increase intracellular reactive oxygen species (ROS) levels and reduce intracellular adenosine triphosphate (ATP) levels, thereby further inhibiting the function of P-gp, increasing intracellular concentration of drugs, and ultimately overcoming MDR in HCC. Hence, the combination of DOX and DSF delivered by DOX/DSF NPs with pH-sensitive and sequentially controlled drug release may provide a new way for MDR of HCC.

Currently, based on the unique spatial structure and properties of three-dimensional ordered macroporous (3DOM) materials, the photocatalytic performance of composites can be effectively enhanced by loading semiconductors with photocatalytic activity on the surface and designing and constructing heterostructures. In this study, polystyrene (PS) microspheres were prepared using the self-assembly technology. In₂S₃@3DOM NiTiO₃-TiO₂ composite was then fabricated via a vacuum impregnation and constant-temperature water bath method, of which the crystal phase and microstructure analysis revealed that In₂S₃@3DOM NiTiO₃-TiO₂ exhibited a well-defined crystal structure and 3DOM morphology. This 3DOM structure provided more reactive sites with a substantial mass transfer capacity, and its slow photon effect could enhance the light absorption. Photoluminescence and photoelectrochemical tests demonstrated that the heterojunction interfaces among In₂S₃, NiTiO₃, and TiO₂ in In₂S₃@3DOM NiTiO₃-TiO₂ effectively promoted the separation of electron–hole pairs and significantly extended the carrier lifetime. Under simulated sunlight conditions, the removal rate of crystal violet (CV) as the target pollutant by In₂S₃@3DOM NiTiO₃-TiO₂ achieved 99.98%. Moreover, with Pt as the cocatalyst, its photocatalytic hydrogen production performance was 12 times higher than of commercial TiO₂. Through active species capture experiments, Mott–Schottky tests, and UV–vis diffuse reflectance tests, the photocatalytic reaction mechanism of the double Z-scheme heterostructure among In₂S₃, NiTiO₃, and TiO₂ was speculated, and the possible photocatalytic degradation pathways were analyzed. The double Z-scheme heterostructure regulated the charge transfer path. It enhanced the separation efficiency of electrons and holes, and the 3DOM slow photon effect strengthened the light capture ability of the composite material, further significantly improving its photocatalytic performance.