Nano Today最新文献

The widespread prevalence of antifungal resistance results in the ineffective treatment of Candida-related infections since current approaches still heavily rely on antifungal drugs such as azoles. Adjuvant therapy is an alternative approach to alleviate this crisis that can re-sensitize multidrug-resistant (MDR) fungi to antifungal drugs. Herein, we report a synergistic strategy to restore antifungal activity of azoles against MDR Candida albicans (C. albicans) through nanotechnology. C. albicans-mediated biosynthetic gold nanoparticles (Ca_AuNPs) exhibit a significant potentiating effect (16–32 folds) on azoles (including fluconazole, itraconazole, and voriconazole) against MDR C. albicans. Mechanistic studies demonstrate that Ca_AuNPs can promote the intracellular accumulation of fluconazole and trigger the biochemical processes including cell structure destruction, membrane potential dissipation, intracellular ROS generation, and ATP level reduction to overcome the fungal intrinsic resistance. We demonstrate that the adjuvant therapy significantly reduces fungal viability and enhances vaginal mucosa regeneration when treating Candida vaginitis-infected mice. This study reveals the potential of biosynthetic nanoparticles as novel adjuvants to extend the lifespan of existing antifungal drugs for the treatment of MDR pathogen-induced infections.

2D/3D perovskite heterojunctions typically yield mixed-phase 2D perovskites, generating multiple quantum wells that impede charge transfer, thereby limiting the potential enhancement of solar cell efficiency. Here, we successfully fabricated phase-pure 2D (n = 2)/3D perovskite heterojunctions via introducing the γ-aminobutyric acid (GABA) ligand, which minimized energetic inhomogeneity, thus favoring interfacial charge transfer through optimized energy band alignment. The ligation between the oxygen atoms in the ligand and the uncoordinated lead in the 3D perovskite triggered a structural transition from cubic to tetragonal at the 3D perovskite surface, ensuring a seamless lattice matching with the 2D perovskite (n = 2), resulting in this optimized configuration. Utilizing this innovative structural configuration, the carrier properties of 2D/3D perovskite thin films have been significantly enhanced, exhibiting diffusion lengths exceeding 1000 nm and a mobility of 3.35 cm² V⁻¹ s⁻¹. Consequently, the fabricated small-area perovskite solar cells exhibited an impressive power conversion efficiency (PCE) of 25.06 %, while the mini-modules (10 cm × 10 cm) attained a maximum PCE of 17.27 %. Furthermore, the passivation of the 2D perovskite layers, coupled with their inherent superior resistance, enabled the unencapsulated target device to maintain outstanding long-term stability, even under challenging environmental conditions of light, heat, and humidity.

Niobium is attracting more and more attention in dental and orthopedic clinical applications. On the one hand, niobium alloy has verified its good biocompatibility, corrosion resistance and mechanical properties; on the other hand, niobium nanomaterials could reduce the osteoclast activation through ROS absorption, which is conducive to bone tissue regeneration. The impressive osteogenesis ability of niobium-based nanomaterials inspired the strategy to load the 2D niobium into bioactive responsive carriers and directly deploy in bone defects to promote bone regeneration efficiently and in situ. Here, a bone cement was constructed through the innovative super-assembled strategy that had integrated the nano-level 2D niobium carbide MXene to the macroscopic 3D GelMA photo-cured frameworks. The super-assembled bone cement can achieve accelerated bone fracture healing and osseointegration in various preclinical mouse models without any detectable toxicity. Mechanistically, 2D Nb₂C bone cement promoted osteoblast activation without altering osteoclast function in vivo. Transcriptomics and chromatin immunoprecipitation revealed that 2D Nb₂C stimulates GATA3-GPNMB signaling to active osteoblasts in mice. In freshly isolated human osteoblasts, 2D Nb₂C stimulated osteoblast activation and calcification. This work proposes a topically effective, non-toxic, low-cost 2D Nb₂C-based bone cement with distinct clinical translational potential in dentistry and orthopedics.

Acute myeloid leukemia (AML) is a rapidly proliferating blood cancer, necessitating treatments that specifically target and swiftly eradicate it. In this study, we develop an AML-specific, apoptotic cell death-inducing protein nanoparticle, AaLS/TRAIL/aCD13Nb, by simultaneously displaying multiple CD13-binding nanobodies (aCD13Nb) and Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) molecules on a single AaLS protein nanoparticle using the SpyCatcher/SpyTag protein ligation system. AaLS/TRAIL/aCD13Nb selectively binds to various CD13-overexpressing AML cell lines and effectively accumulates near U937 AML tumor sites through systemic administration, demonstrating its AML targeting capabilities. The tight binding of AaLS/TRAIL/aCD13Nb to CD13-overexpressing AML cells, mediated by aCD13Nb, results in close and continuous contact between TRAIL molecules and death receptors, triggering robust apoptotic cell death. Systemic administrations of AaLS/TRAIL/aCD13Nb into U937 AML-engrafted NSG mice significantly reduce the AML burden and nearly double the mice’s survival period, especially under advanced and severe AML conditions. Collectively, our study paves the way for targeted therapies in AML, utilizing protein nanoparticles as nanoplatforms. Substantial therapeutic efficacy across various cancers can be achieved by strategically combining cancer-specific targeting ligands with apoptotic cancer cell death-inducing molecules, tailored to specific cancer types.

Flexible sensors simultaneously with property of hydrogel-like low modulus/room temperature ultra-fast self-healing and with elastomer-like durability /environmental stability and underwater adhesion for bioelectronics has not been reported. A low modulus hydrogel-like elastomer that achieves ultrafast self-healing through molecular chain entanglement at room temperature was prepared based on furfuryl alcohol-modified poly(sebacate glyceride) (PGS) prepolymer, furfuryl alcohol-modified poly(ionic liquid) and bismaleimide by Diels-Alder (DA) reaction. The conductive elastomer-based flexible sensors exhibit hydrogel-like properties of low modulus (6.41 kPa) and ultra-fast self-healing (98 % self-healing efficiency within 5 s). The elastomer also possesses rapid subzero and underwater self-healing properties within 5 s. Moreover, PGS-0.2DA-0.2PIL exhibits pressure sensitive adhesive properties and can be adhered/re-adhered in water. The flexible sensor shows elastomer-like high durability, high environmental stability, multiple recyclability and reusability, and it exhibits wide detection ranges, fast response time, low hysteresis, anti-freezing, anti-bacterial and good biocompatibility. The flexible sensors can accurately identify micro-expressions/eye rotation, monitor human movement/health, detect ECG/EMG signals and control robotic arm movements. In conclusion, a new strategy for design of hydrogel-like conductive elastomers via molecular structure design is proposed, and the elastomers-based flexible sensors with low modulus, rapid self-healing and durability/environmental stability show great promising for bioelectronic applications.

Fluorite-based ferroelectric thin films offer significant potential as candidates for next-generation non-volatile memory logic devices due to their excellent compatibility with existing silicon-based semiconductor technology. However, the challenge lies in the complex preparation of stable fluorite based ferroelectric thin films, as several metastable phases typically exist under narrow and unpredictable experimental conditions, such as harsh temperature, specific thickness, unique strain conditions et al. Here, stable and cost-effective ZrO₂ ferroelectric thin film with tetragonal-orthorhombic-monoclinic phase transition can be fabricated in a wide chemical-processing window. Notably, within a considerable temperature range (∼200 °C) and thickness range (∼250 nm), the ZrO₂ films show robust ferroelectric polarization with a peak value of around 15 μC/cm², comparable to previous reports. The stable ferroelectric phase range can be controlled by adjusting oxygen content and implementing strain engineering. Intriguingly, we further achieve the highest remanent polarization of 20.15 μC/cm² and the lowest coercive field of 1.18 MV/cm by a combination of annealing times and strain engineering. Synchrotron-based X-ray absorption spectroscopy has revealed oxygen tetrahedral distortions, indicating the transition of from the tetragonal to orthorhombic phases. Furthermore, the migration of oxygen ions between the ferroelectric and antiferroelectric phase under electric field activation has been directly detected through integrated differential phase-contrast scanning transmission electron microscopy. This study significantly contributes to the further development of the fabrication procedure and enhances the understanding of the ferroelectric origin for ZrO₂-based fluorite ferroelectric thin films.

Entropy engineering in thermoelectric materials involves a deliberate manipulation of entropy-related effects to boost performance. It revolves around designing materials to capitalize on entropy-driven changes, breaking conventional trade-offs between properties like electrical and thermal conductivity for improved efficiency. Entropy engineering fosters higher crystal symmetry, altering the Seebeck coefficient by augmenting degenerate valleys in the band structure. The introduction of significant mixing entropy mitigates strain energy, enhancing structural stability. Conversely, severe lattice distortion, atomic mass fluctuations, lattice anharmonicity, multiscale microstructures, and point defects lead to potent scattering of phonons, which suppresses thermal transport properties. This study comprehensively explores the effectiveness of entropy engineering in diverse compounds, aligning with the status and challenges in this field. These insights will guide researchers in refining material design and properties, advancing high-performance thermoelectric materials and devices to revolutionize energy conversion and stimulate sustainable technological advancements.

Challenges in characterizing and quantifying nanoplastics within the human body hinder understanding of their transport, biotransformation, and potential for cellular penetration and barrier crossing. By implementing an innovative analytical workflow, including incorporation of gadolinium (Gd) as a tracer into the polymer matrix of nanoplastics, the fate of nanoplastics relative to an in vitro blood-brain barrier (BBB) model is elucidated in the absence or presence of a biomomolecule corona. The nanoplastics were incubated in human plasma for 5 min, 1 h, 6 h, and 24 h, after which the absorbed proteins and lipids (biocorona) were determined. A total of 268 proteins were identified in the biological coronas on polystyrene (PS) and polyvinyl chloride (PVC) nanoplastics, with the initial compositions being broadly similar on both PS and PVC. Both nanoplastics exhibited a strong affinity for phosphatidylcholines (PC) and lysophosphocholines (LPC) from human plasma. The inherent chemical composition of the nanoplastics plays a pivotal role in the corona’s evolution over time. Human induced pluripotent stem cell (iPSC)-derived endothelial cells (iECs) and astrocytes were exposed for 2 h to 5 µg L⁻¹ of pristine nanoplastics or nanoplastics covered with a biological corona (following incubation in plasma for 6 h). A relatively low concentration of PS and PVC nanoplastics was determined to be present within the cellular layer of the BBB. The number of PVC nanoplastics crossing the BBB was higher than the number of PS nanoplastics. The presence of a biological corona on these particles decreases their uptake and transcytosis. This understanding might further the development of preventive measures or therapeutic strategies to counteract potential nanoplastic-induced neurotoxicity, and provide a foundation for development of in silico models to predict the neurotoxic implications of nanoplastics.

Mixed-addenda polyoxometalate (e.g., PMo_xW_12-x) by “orbital engineering” allows the functionalization of the single-addenda cluster surface, which offers new electronic properties. However, the well-known agglomeration phenomenon greatly limits the full understanding of its unique redox properties. It makes sense to fully stimulate the intrinsic multi-electron activity of mixed-addenda polyoxometalate by confining engineering to apply in energy technology. With the verification of potential candidate PMo₆W₆ possessing remarkable stability with fully exposed activity sites in a confined state by theoretical analysis, we achieve the precise confinement of the single PMo₆W₆ molecule in porous carbon (PC) with a matched pore aperture (PMo₆W₆@PC). As a result, PMo₆W₆@PC-based supercapacitor shows high energy densities of 0.308 mWh cm⁻² at power densities of 43.2 mW cm⁻², outperforming most polyoxometalate-based supercapacitors. Moreover, the device exhibits a capacity retention of over 80.4 % at 8 mA cm⁻² after 8000 cycles. This improved electrochemical redox activity may be ascribed to the strong orbital electronic coupling between W and Mo atoms of PMo₆W₆ by confinement engineering. This work proves that the confined PMo₆W₆ can maximize the advantages of PMo₁₂O₄₀ and PW₁₂O₄₀, which provides a theoretical basis for other mixed-addenda polyoxometalate species.

The critical phase transition temperature (Tc) of Cu₂Se thermoelectric nanomaterials has been a focal point of extensive research, yet the quantification of surface energy on Tc is frequently ignored. In this paper, we systematically investigate the impact of both the width/thickness and surface configuration of Cu₂Se nanobridges (NBs) on Tc. We find that the Tc decreases with size reduction, which becomes particularly accelerated when the size decreases to a few nanometers. Additionally, the NBs with higher energy surfaces exhibit lower Tc. Then we propose an optimized thermodynamic model to quantify the combined effect of size and surface energy on Tc in Cu₂Se NBs, which provides an approach to predict Tc in Cu₂Se and other thermoelectric nanomaterials. Our study facilitates the understanding of the dependence of Tc on size and surface in Cu₂Se, with an eye towards the stable room temperature thermoelectric applications of Cu₂Se nanomaterials.