Science and Technology of Advanced Materials最新文献

Inhaled nitric oxide (iNO) is a powerful therapy for the treatment of various cardiopulmonary and respiratory diseases. However, access to iNO therapy is often limited by the necessity of cumbersome gas tanks and/or elaborate gas blending apparatus. Here, we report a lightweight, inexpensive, and maintenance-free tablet that autonomously generates a therapeutic quantity of NO in air. The tablet is composed of a thimble filter paper containing a powdery mixture of nitrite (NO₂ ^‒)-type layered double hydroxide (NLDH) and ascorbic acid loaded on silica gel (AASiO₂). NLDH by itself generates trace amounts of NO in the air due to the left-shifting of the protonation equilibrium of NO₂ ^‒ by aerial CO₂ and H₂O (2[NO₂ ^‒]_LDH + CO₂ + H₂O $\rightleftharpoons$ 2HNO₂↑ + [CO₃ ^2‒]_LDH), which is followed by disproportionation of 2HNO₂ to NO, NO₂ and H₂O. In contrast, it was found that the protonation equilibrium can be shifted to the right side when volatile acid products (HNO₂ and NO₂) are readily converted to neutral NO over the AASiO₂ reductant. Based on this, even a single tablet (containing 0.30 g NLDH and 0.90 g AASiO₂) generates 5 ~ 20 ppm NO at 0.5 L/min for 24 h, which is sufficient to be useful for the relief of severe hypoxia caused by persistent pulmonary hypertension of the newborn (PPHN). Moreover, the tablet can be activated by exhaled breath for high-dose iNO therapy (80 ~ 180 ppm for several hours), revealing its potential utility for treating viral pneumonia. The NO tablet can be stored stably over long periods at ambient temperature in a gas barrier bag and has the potential to break the logistical, financial, and operational barriers that have long existed for the widespread implementation of iNO therapy.

We demonstrated the epitaxial lateral overgrowth of m-plane α-Ga₂O₃ using halide vapor phase epitaxy. An m-plane α-Ga₂O₃/sapphire template with a patterned SiO₂ mask was used as the substrate. The highest lateral growth rate for a radial spoke-wheel patterned mask was obtained when the spoke was perpendicular to the $\left(11\stackrel{-}{2}3\right)$ direction. In this case, the lateral-to-vertical growth rate ratio (L/V ratio), with L defined as the rate of increase in the width of an elongated α-Ga₂O₃ island, was as large as 5.8. This ratio was greater than that reported for an m-direction stripe mask on a-plane α-Ga₂O₃ by a factor of 3.3 and that for an a-direction stripe mask on c- and m-plane α-Ga₂O₃ by a factor of 13. The epitaxial lateral overgrowth (ELO) of α-Ga₂O₃ on a stripe mask (window/mask widths of 2.5 μm/7.5 μm) perpendicular to $\left(11\stackrel{-}{2}3\right)$ resulted in the selective nucleation of elongated α-Ga₂O₃ islands with a flat triangular cross-section on the window areas and their coalescence into a compact film. Transmission electron microscopy revealed that the dislocation density in the laterally grown area decreased drastically because the propagation of dislocations in the seed layer was effectively blocked by the mask. We believe these results greatly contribute to the realization of m-plane α-Ga₂O₃-based future power devices.

Extracellular vesicles (EVs) hold significant promise as biomarkers and therapeutics, yet their isolation remains challenging due to their low abundance and complex sample matrices. Here, we introduce EV-Osmoprocessor (EVOs), a novel device that leverages osmosis-driven filtration for rapid and efficient EV isolation. EVOs employs a high osmolarity polymer solution to concentrate EVs while simultaneously removing smaller contaminants. Compared to traditional methods such as ultracentrifugation and precipitation, EVOs offers speed and convenience, achieving a 50-fold volume reduction in under 2 h. Our results show that EVOs retained EVs and removed >99% albumin from the cell conditioned culture medium (CCM). The isolated EVs exhibited a particle size distribution centered around 140 nm, which was very similar to EVs isolated via precipitation or ultracentrifugation. The standalone EVOs process achieved a particle:protein ratio (EV purity) of ~10⁷ particles/µg protein. Comprehensive characterization, including cryo-electron microscopy, validation of protein markers and known miRNA cargo confirmed the successful isolation of EVs. Functional assays, based on protection of cardiomyocytes from hypoxia/reoxygenation injury, demonstrated the bioactivity of EVOs-isolated EVs. Furthermore, we show that EVOs can be used to concentrate 30 ml of CCM into a 0.5 ml solution, which was then further processed with size-exclusion chromatography (SEC), improving EV purity to ~10⁹ particles/µg protein. This work establishes EVOs as a promising tool for EV research and clinical applications, offering a streamlined approach to EV isolation with enhanced analytical performance.

Intense terahertz (THz) radiation in free space offers multifaceted capabilities for accelerating electron, understanding the mesoscale architecture in (bio)materials, elementary excitation and so on. Recently popularized spintronic THz emitters (STEs) with their versatility such as ultra-broadband, large-size and ease-for-integration have become one of the most promising alternative for the next generation of intense THz sources. Nevertheless, the typical W | Co ${ }_{20}$ Fe ${ }_{60}$ B ${ }_{20}$ | Pt necessitates an external-magnetic-field to saturate magnetization for stable operation, limiting its scalability for achieving higher THz field with uniform distribution over larger sample areas. Here we demonstrate the methodologies of enhancing the high-field THz radiation of external-magnetic-field-free IrMn ${ }_3$ | Co ${ }_{20}$ Fe ${ }_{60}$ B ${ }_{20}$ | W trilayer heterostructure via optimizing the substrate with superior thermal conductivity and integrating a one-dimensional photonic crystal (PC) structure to maximize the radiation efficiency. Under the excitation of a 1 kHz Ti: sapphire femtosecond laser amplifier with central wavelength of 800 nm, pulse duration of 35 fs, and maximum single pulse energy of 5.5 mJ, we successfully generate intense THz radiation with focal peak electric field up to 650 kV/cm with frequency range covering 0.1-5.5 THz from MgO-coated sample without external-magnetic-fields. These high-field STEs will also enable other applications such as ultra-broadband high-field THz spectroscopy and polarization-based large-size strong-field THz imaging.

This study presents an approach for fabricating durable superhydrophobic surfaces on 3D-printed structures inspired by the architectural design of beehives. Using fused deposition modeling (FDM) 3D printing technology, hexagonal macrostructures were fabricated using polylactic acid (PLA) filament. These structures were designed to protect an inner layer of hydrophobic nanoparticles, which were deposited by a squeegee coating method and immobilized by a photocurable resin. The relationship between hexagonal area size (ranging from 24 to 200 mm²) and the durability of superhydrophobic properties under frictional stress was systematically investigated. Wettability and surface morphology analyses performed before and after the friction tests showed that structures with hexagonal areas between 40 and 80 mm² retained superhydrophobicity even after 100 friction cycles, while larger hexagonal configurations exhibited diminished performance. To elucidate the underlying mechanisms, a theoretical model based on the Cassie-Baxter equation was developed and compared with experimental values alongside surface observations. This research advances the development of durable and functional superhydrophobic surfaces in 3D-printed materials, with promising implications for industries requiring water-repellent and self-cleaning technologies.

Ferroptosis, a form of non-apoptotic cell death, is emerging as a promising strategy for cancer therapy. Artesunate (ART), an extract obtained from the traditional Chinese medicine Qinghaosu, has been shown to exhibit anti-cancer activity by inducing ferroptosis in cancer cells. While previous research has focused on incorporating ART monomer into drug delivery systems for enhanced cancer targeting, this study presents 2-methacryloyloxyethyl ART polymer (poly(ARTEMA)), a novel polymer synthesized from ART for the first time. Our goal was evaluation of poly(ARTEMA) anticancer potential on breast cancer cells. First, we synthesized ARTEMA using esterification followed by its polymerization using the reversible addition-fragmentation chain transfer (RAFT) polymerization method. We evaluated its mechanism of action, focusing on two key pathways: temperature-triggered singlet oxygen generation and ferrous ions (Fe²⁺) release, both of which contribute to ferroptosis. Our results demonstrate that poly(ARTEMA) selectively generates singlet oxygen and Fe²⁺ due to the endoperoxide crosslinks, leading to cell death in breast cancer cells. We also investigated the anti-cancer potential of poly(ARTEMA) on breast cancer cells with and without a ferroptosis inhibitor. The IC₅₀ values were 125 µM for the MCF-7 cancer cell line and 300 µM for the normal MCF-10 cell line, indicating enhanced toxicity toward cancer cell lines. These findings suggested that poly(ARTEMA) induces ferroptosis in cancer cells and may serve as a promising candidate for cancer therapy with minimal cytotoxicity. To the best of our knowledge, this report may be the first that successfully synthesized poly(ARTEMA) using ART, with its anticancer potential evaluation.

4-Phenylbutyric acid (PBA) is a small molecule with promising therapeutic potential for treating various diseases, including cancer and neurodegenerative disorders, due to its dual ability to reduce endoplasmic reticulum stress and inhibit histone deacetylases. However, its clinical application is hindered by rapid clearance from the body, necessitating frequent dosing that increases the risk of adverse effects. To address these limitations, we developed a nanoparticle-based prodrug (Nano^PBA) utilizing the amphiphilic block copolymer poly(ethylene glycol)-b-poly(vinyl 4-phenylbutyrate) [PEG-b-P(VPBA)]. This system self-assembles into micelles, enabling controlled and sustained PBA delivery. The synthesis and characterization of Nano^PBA revealed its high stability under physiological conditions and enzyme-responsive PBA release. Nano^PBA demonstrated a controlled release profile in vitro, reducing burst release while maintaining therapeutic efficacy. Cytotoxicity assays using normal cell lines, including endothelial cells (BAEC), macrophages (RAW264.7), and rat gastric cells (RGM-1), showed minimal cytotoxic effects compared to the parent low-molecular-weight PBA. Furthermore, in vivo studies conducted in healthy C57BL/6J mice confirmed Nano^PBA's biocompatibility, with no significant adverse effects observed at therapeutic doses ranging from 200 to 500 mg-PBA/kg via oral administration. In conclusion, Nano^PBA offers a controlled release profile, enhanced biocompatibility, and reduced toxicity, addressing the limitations associated with conventional PBA administration. These attributes make Nano^PBA a promising candidate for improving the therapeutic efficacy and safety of PBA in clinical applications, particularly in diseases where maintaining consistent drug levels is crucial for treatment outcomes.

This study introduces a novel supramolecular thermotropic columnar liquid-crystalline (LC) electrolyte tailored for high-performance ionic electroactive polymer (iEAP) actuators. The electrolyte is designed by integrating lithium salts into a taper-shaped molecule with bisphosphate moieties (BPO), which self-assembles into a columnar hexagonal (Col_h) phase, forming 3D continuous ion-conductive pathways. This architecture achieves high ionic conductivity of up to 2 × 10^-4 S cm^-1 at room temperature. An actuator was fabricated by embedding this electrolyte into a microporous polyethylene membrane, sandwiched between PEDOT:PSS electrodes. The resulting device exhibits exceptional performance, achieving a bending strain of 0.52% and a force output of 0.5 mN under a ± 2 V, along with outstanding durability, retaining its performance over 9000 cycles. These results underscore the potential of 3D ion-conductive LC electrolytes in advancing iEAP actuator technologies, paving the way for innovative applications in tactile interfaces and soft robotics.

Dynamically thermoresponsive biomaterials, particularly those utilizing poly(N-isopropylacrylamide) (PNIPAAm), have attracted much attention in biomedical applications due to their reversible phase transition near body temperature. These biomaterials provide innovations across drug delivery system, chromatography, and tissue engineering. Molecular designs, such as the incorporation of hydrophilic comonomers or graft copolymers in PNIPAAm hydrogels, enhance rapid kinetics of the gels when jumping the temperature across the phase transition temperature, because of avoiding 'skin layer' formation on the surface of the gels. Nanocarriers possessing PNIPAAm coronas facilitate spatial drug delivery and temporally on-demand drug release to targeted cancers in combination with hyperthermic therapy. Downsizing of PNIPAAm hydrogels accelerates the kinetics of shrinkage/swelling, leading to applications as thermoresponsive chromatographic matrices and cell cultureware. PNIPAAm-modified surfaces support thermoresponsive cell culture systems for the non-invasive recovery of intact cell sheets, enabling advanced regenerative therapies and layered 3D tissue formation. Recent developments also integrate growth factor delivery for sustained cell stimulation on culturewares. Newly developed biomaterials, including dynamically thermoresponsive PNIPAAm, are expected to expand the opportunity for novel treatment technologies such as targeted therapies and regenerative medicine.

Catechol-containing polymers inspired by marine mussels have gained significant interest in recent years, leading to applications in several fields. Among these polymer systems, poly(vinylcatechol-styrene) (PVCS) has become a popular option due to its exceptional underwater adhesion strength, with readily available monomers and diverse synthetic routes being available. However, the translation of any novel adhesive chemistry from academic research to real-world applications can be challenging. Acrylates, epoxies, and urethanes were introduced to markets over half a century ago and remain dominant. However, bonding in wet environments remains lacking. The work presented here addresses this gap by focusing on the formulation of PVCS-based adhesives for conditions outside of the research lab. An emphasis was placed on handling properties when working underwater. A collection of different substrates were bonded together and several commercial glues provided benchmarks. Environmental conditions were studied to broaden the potential applications of PVCS adhesives in underwater settings. By optimizing formulations, we present an adhesive system that retains the superior underwater bonding of PVCS while also offering enhanced workability. This approach may help open the door to utilization of a new adhesive chemistry for underwater applications.