ACS Applied Nano Materials最新文献

Biogenic amines (BAs), especially histamine, are important indicators for assessing the quality and edibility of aquatic products. Rapid detection of histamine is of great significance for food safety. Herein, a smartphone-integrated fluorescence sensor based on Cu NCs/CDs and a Cu NCs/CDs-PVA hydrogel sensor was designed for histamine ratiometric detection and on-site monitoring of the shrimp spoilage process. The self-assembled induced luminescence of copper nanoclusters (Cu NCs), first prepared with 3,5-bis(trifluoromethyl)benzenethiol (TFBT) as a ligand, was used for the sensitive detection of histamine by the interaction between the metal and the imidazole group. The fluorescence emission peak of CDs could be used as a reference peak because it has no overlap with the emission of Cu NCs. The fluorescence peak of CDs hardly changed, and the fluorescence of Cu NCs decreased with the addition of histamine, which enabled histamine fluorescence ratiometric detection. This method exhibits an excellent linear relationship between the fluorescence intensity ratio (F₄₃₇/F₆₀₅) and histamine concentrations ranging from 40−120 μM, with a detection limit of 0.37 μM. Furthermore, Cu NCs/CDs were introduced into the hydrogel recognition system, and the Cu NCs/CDs-PVA hydrogel was utilized for histamine determination and on-site monitoring of shrimp spoilage. The as-prepared hydrogel sensor offers a convenient method for on-site monitoring of food safety.

Surface-enhanced infrared absorption spectroscopy (SEIRAs) holds immense potential for trace biomolecular detection. Here, we report a high-performance SEIRAs biosensing platform based on a two-dimensional (2D) monolayer graphene/nanostructured metal metasurface hybrid heterostructure. The platform synergistically couples deep-subwavelength nanoscale electromagnetic hotspots with 100 nm inter-unit gaps with nanomaterial-induced interfacial molecular enrichment. The hybrid sensor amplifies the vibrational fingerprint signals of immunoglobulin G at characteristic amide bands, achieving a low detection concentration down to 3 pM. Furthermore, protein spike-and-recovery assays in unprocessed artificial sweat and urine yield excellent recovery rates. Density functional theory calculations reveal that graphene provides a seamless, non-site-specific π−π physisorption matrix, effectively relieving interfacial steric repulsion and maximizing molecular coverage within plasmonic hotspots. This work provides a robust theoretical framework and an innovative experimental paradigm for the development of next-generation, highly sensitive mid-infrared biosensing technologies.

MXenes have emerged as promising two-dimensional nanomaterials for cancer nanomedicine owing to their tunable surface chemistry, strong photothermal response, and favorable biocompatibility. Herein, we develop a gold nanoparticles-decorated MXene nanoplatform (Au@Mo₂TiC₂T_x-PEG) for synergistic photothermal and catalytic tumor therapy. The nanoplatform is constructed by anchoring Au nanoparticles onto Mo₂TiC₂T_x nanosheets, followed by polyethylene glycol modification to improve physiological stability and biocompatibility. The as-prepared Au@Mo₂TiC₂T_x-PEG exhibits strong near-infrared absorption with a photothermal conversion efficiency of 39.8%, enabling effective photothermal therapy under 808 nm laser irradiation. Notably, this nanoplatform possesses intrinsic glucose oxidase (GO_x)-like and peroxidase (POD)-like activities, which initiate a cascade catalytic reaction within the tumor microenvironment. Glucose oxidation-mediated H₂O₂ generation, which subsequently converts into highly cytotoxic reactive oxygen species, while simultaneously depleting intracellular glutathione disrupts tumor redox homeostasis. The integrated catalytic and photothermal effects synergistically enhance oxidative stress, promote tumor cell apoptosis, and improve therapeutic efficacy. Both in vitro and in vivo studies reveal that Au@Mo₂TiC₂T_x-PEG effectively suppresses tumor progression, achieving a tumor inhibition rate of 94% under 808 nm laser irradiation with minimal systemic toxicity. These findings demonstrate the potential of the MXene-based nanoplatform to integrate catalytic metabolism regulation and photothermal activation, providing a powerful strategy for precision cancer therapy.

Two-dimensional transition-metal dichalcogenide (TMD) nanojunctions are promising candidates for nanoscale thermoelectric energy conversion. In this work, we investigate the thermoelectric properties of gate-tunable Pt−WSe₂−Pt nanojunctions in the ballistic transport regime based on periodically nitrogen-doped monolayer WSe₂ superlattices. Electronic transport properties were calculated using density functional theory combined with the nonequilibrium Green’s function formalism (DFT-NEGF), while phonon thermal conductivities were obtained from nonequilibrium molecular dynamics (NEMD) simulations. Periodically nitrogen-doped WSe₂ superlattices with 4-, 6-, and 8-Row doping periodicities were systematically investigated and compared with pristine WSe₂. The results show that periodic nitrogen doping reduces the band gap, sharpens transmission band edges, and suppresses phonon thermal conductivity. These effects lead to substantial enhancements in thermoelectric performance. Furthermore, the 4-Row superlattice achieves the highest thermoelectric figure of merit, reaching ZT = 2.587 at 500 K, compared with ZT = 0.422 for pristine WSe₂. The enhanced performance originates from the combined effects of improved electronic transport engineered by band gap and reduced thermal conductivity by more scattering due to superlattice. These findings demonstrate that periodically nitrogen-doped WSe₂ superlattices provide an effective route for band-structure and phonon engineering, offering a promising strategy for high-efficiency thermoelectric energy conversion in two-dimensional nanoscale devices.

This study presents the design and synthesis of multifunctional magnetic cellulose nanocrystal (CNC) composites engineered for targeted adsorption and broad-spectrum antimicrobial applications. The nanocomposites were fabricated by anchoring mixed-valence Fe₃O₄ magnetic nanoparticles on eco-friendly CNC frameworks, followed by surface functionalization with benzalkonium chloride (BC), a potent quaternary ammonium biocide. Both sulfated (S) and TEMPO-oxidized CNC (T) variants were investigated across Fe₃O₄:CNC mass ratios of 1:2 and 1:4. Comprehensive structural, magnetic, and morphological characterization confirmed successful surface modification, superparamagnetic responsiveness, and uniform component dispersion. Thermogravimetric analysis confirmed precise compositional tailoring, capturing up to 87 wt.% inorganic magnetite core fractions, 11−34 wt.% organic CNC matrix, and up to 11 wt.% bound BC surfactant. Density functional theory (DFT) simulations complemented these insights by mapping favorable BC binding configurations and localized electronic-structure alterations. Equilibrium adsorption isotherms followed a dominant Langmuir monolayer pathway, with saturation capacities of 178−224 mg g⁻¹ and Langmuir correlation coefficients (R²) of 0.97−0.995. Quantum-chemical binding maps, together with robust within-variant interfacial charge inversions (e.g., from −22.1 to +8.5 mV for the 1:2 S formulation and from −20.4 to +11.2 mV for the 1:2 T formulation after BC addition), point to a cooperative physisorption−chemisorption transport mechanism. In vitro antibacterial assays showed pronounced, concentration-dependent inhibition zones of 7.9−12.8 mm against both Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) foodborne pathogens, with bactericidal performance primarily correlating with BC loading and, to a lesser extent, with the underlying CNC surface chemistry. Together with the high adsorption capacity and magnetic recoverability of the CNC-Fe₃O₄ carrier, these results position BC@CNC-Fe₃O₄ nanocomposites as a promising platform for applications such as smart disinfection and active food-contact materials.

The application of nanomaterials in agriculture has emerged as a promising strategy to improve crop productivity, optimize agrochemical delivery, and support sustainable crop management. However, the development of agricultural nanoformulations remains largely empirical, particularly for biodegradable organic nanomaterials, owing to the limited mechanistic understanding of plant−nanomaterial interactions. Recent advances in omics and multiomics approaches are transforming this scenario by revealing how nanomaterials actively modulate molecular, metabolic, and physiological processes rather than acting solely as passive delivery systems. In this review, we examine how omics approaches are reshaping our understanding of plant responses to organic nanomaterials, highlighting emerging patterns of biological reprogramming, the influence of nanomaterial physicochemical properties on these responses, and current challenges in experimental standardization, multiomics integration, mechanistic interpretation, and field validation. The available evidence does not support a universally optimal nanomaterial, highlighting the need for biologically informed design strategies tailored to material properties, plant responses, and application conditions. Finally, we propose omics-guided design as a conceptual strategy in which biological information becomes an active engineering parameter for rationally developing next-generation organic nanomaterials. This perspective highlights how molecular information can support more targeted, biologically informed, and environmentally responsible nanoformulation strategies.

We report a facile and environmentally benign strategy to produce highly stable aqueous colloids of the CsPbBr₃@CsPb₂Br₅ core−shell nanocomposites via water-driven in situ reconstruction. A combination of X-ray diffraction, energy-dispersive X-ray spectroscopy, and real-time conductometry confirms the water-induced phase transformation. This reconstruction process involves the selective leaching of Cs⁺ and Br⁻ ions during brief ultrasonication in water from the multiphase CsPbBr₃/Cs₄PbBr₆ precursor, synthesized via a facile, low-toxicity ligand-assisted reprecipitation method. Transmission electron microscopy establishes the matrix-inclusion nanocomposite geometry, confirming that monodisperse orthorhombic CsPbBr₃ cores with a mean diameter of (3.58 ± 0.57) nm are embedded within the tetragonal CsPb₂Br₅ matrix. Time-resolved photoluminescence spectroscopy proves effective surface defect passivation, exhibiting an extension of the average carrier lifetime from 4.43 ns to 5.30 ns upon shell crystallization. Driven by this defect passivation, photoluminescence spectroscopy confirms a maximum photoluminescence quantum yield of 48.6% after 72 h of storage. Laser Doppler microelectrophoresis determines a high positive surface potential of (74.5 ± 13.7) mV ensuring long-term colloidal stability exceeding >1000 h without sedimentation. Time-dependent fluorescence spectroscopy reveals a continuous hypsochromic shift of the emission peak from 543 nm to 519 nm (at 120 h) and 491 nm (at 1152 h), governed by subtractive water-driven etching and enhanced quantum confinement. This self-encapsulation framework provides a robust solution to halide perovskite instability in polar media.

Conventional etching routes for Al-containing MAX phases rely primarily on fluoride-based chemistries, which provide limited control over surface terminations and motivate the development of alternative etching strategies. To address this, CuCl is evaluated as a Lewis acid molten salt etchant for Al removal from Nb₄AlC₃, and DFT reaction-energy calculations are used as a pre-experimental screening tool to evaluate the energetic plausibility of the proposed reaction pathway. Reaction-energy (ΔE_rxn) values for the selected stoichiometric steps indicate that the corresponding product configurations are lower in electronic energy than the reactant configurations within the adopted DFT model. Projected density of states (PDOS) calculations were also performed to track how the electronic structure evolves across the reaction, indicating retention of the metallic Nb−C electronic framework following Cl termination. Guided by these computational findings, Nb₄C₃T_x is synthesized by reacting Nb₄AlC₃ with CuCl at 700 °C for 8 h. X-ray diffraction (XRD) showed a shift of the (002) reflection from 7.55° to 6.55° (2θ), indicating interlayer expansion associated with Al removal and Nb₄C₃T_x formation. Field emission-scanning electron microscopy (SEM) imaging shows the layered nanoscale morphology characteristic of etched Nb₄C₃T_x, and High-resolution transmission electron microscopy (HRTEM) confirms that hexagonal structural ordering was retained, with resolved lattice fringes of 0.26 nm. The X-ray photoelectron spectroscopy (XPS) confirms the presence of Nb−C bonding environments together with Cl surface terminations consistent with the Cl-containing surface chemistry considered in the DFT model. The calculated reaction energies represent static electronic energies at approximately 0 K and do not include finite-temperature Gibbs free energies, activation barriers, or reaction kinetics at 700 °C; therefore, they provide a comparative screening criterion rather than independent proof of reaction spontaneity or the experimental mechanism. Altogether, these results demonstrate the potential of DFT-assisted energetic screening for selecting molten-salt etchants and controlling MXene surface chemistry, with relevance to electrochemical applications such as energy storage and sensing applications.

Gold nanoparticle (GNP) radiosensitization is influenced by particle shape and the protein corona acquired in biological environments. We investigated how GNP shape and a preformed human plasma protein corona affect the radiation response of SH-SY5Y neuroblastoma cells exposed to 6 MV X-rays. PEGylated gold nanospheres (PEG-GNSp), nanorods (PEG-GNR), and nanostars (PEG-GNS) were characterized by transmission electron microscopy, UV−visible spectroscopy, dynamic light scattering, zeta-potential analysis, and proton nuclear magnetic resonance (¹H NMR) spectroscopy, while hard-corona protein profiles were examined by LC−MS-based proteomics. Cellular association was evaluated by flow cytometry using rhodamine B-conjugated PEG (PEGRb)-labeled GNPs, with qualitative localization by confocal laser scanning microscopy; cell-associated gold was measured separately by graphite furnace atomic absorption spectrometry (GFAAS). Radiation response was assessed by metabolic activity, clonogenic survival, γH2AX, and post-irradiation reactive oxygen species measurements. PEGRb-associated fluorescence followed PEG-GNR > PEG-GNS > PEG-GNSp and decreased after corona formation for all three shapes, whereas GFAAS showed a different pattern of cell-associated gold. Hard-corona profiles showed shape-associated differences in protein representation, with greater coagulation/contact-system-associated proteins for PEG-GNR and relatively greater immunoglobulin-associated proteins for PEG-GNSp and PEG-GNS. PEG-GNS + PC showed the lowest D₅₀ (0.81 Gy) and the largest numerical SER₅₀ (1.49; 95% CI, 0.85−2.61), although the confidence interval included unity. PEG-GNS + PC also showed the highest mean γH2AX response at 6 Gy, whereas delayed DCF-detectable oxidative activity was greatest for PEG-GNR. These findings indicate that GNP shape and the acquired protein corona are associated with distinct radiation-response patterns not captured by any single measured cellular parameter. The results support considering nanoparticle shape and corona-associated interfacial properties together when developing GNP-based radiosensitizers.

Vitamins are essential micronutrients, and their deficiency can cause serious health issues, making rapid and sensitive analytical detection crucial. This study presents a synthesis method to obtain fluorescent trypsin (Tryp)-stabilized nickel nanoclusters (NiNCs) for the cascade detection of VB₆ PLP and PN via the displacement approach. The fluorescent Tryp−NiNCs were synthesized using a simple one-pot chemical reduction method, with Tryp protein acting both as a stabilizing and reducing agent. The synthesized Tryp−NiNCs exhibit cyan-blue fluorescence emission at 490 nm (λ_ex = 380 nm). For the sensing application, pyridoxal-5′-phosphate (PLP) was functionalized over the surface of Tryp−NiNCs in situ via the formation of a weakly fluorescent internal aldimine complex, PLP_Tryp−NiNCs. Further, when the PLP_Tryp−NiNCs complex was interacted with 2-aminophenylboronic acid (2APBA), the internal aldimine complex converted into an external aldimine complex 2APBA_PLP that restored the fluorescence emission of Tryp−NiNCs at 490 nm. The fluorescent nanoassembly of 2APBA_PLP@Tryp−NiNCs incorporates 2APBA_PLP and Tryp−NiNCs. Subsequently, when PN was introduced into the 2APBA_PLP@Tryp−NiNCs nanoassembly, the 2APBA_PLP complex hydrolyzed and displaced PLP, which quenched the fluorescence emission at 490 nm due to the reversible formation of PLP_Tryp−NiNCs. The detection limit for PN was estimated to be 0.37 μM with a linearity range of 2.50−26.75 μM. The developed method was applied to quantify PN in human urine (98.64−103.06%) and serum (96.42−101.36%) using the spiking method.