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The COVID-19 pandemic has underscored the urgent need for broad-spectrum antivirals (BSAs) capable of countering diverse and rapidly emerging viral threats. Unlike virus-specific drugs, BSAs offer cross-family protection and can serve as adaptable therapeutic platforms for pandemic preparedness. Advances in nanotechnology have further strengthened this approach by improving the solubility, stability, and targeted delivery of antiviral agents. Several repurposed drugs, such as niclosamide, favipiravir, remdesivir, nitazoxanide, and zinc-ionophores, have demonstrated potential broad-spectrum activity when formulated at the nanoscale. These nanoengineered platforms enhance pharmacokinetic performance, tissue penetration, and bioavailability, thereby enabling lower effective doses and reduced systemic toxicity. Such nanotechnological strategies not only improve antiviral efficacy across multiple viral families, including Coronaviridae, Flaviviridae, Orthomyxoviridae, and Poxviridae, but also support scalable, cost-effective production suitable for global deployment. By integrating drug repurposing with nanoengineering, BSAs can form the cornerstone of future pandemic preparedness, bridging the gap between laboratory innovation and rapid clinical response to emerging infectious diseases.

The phenomenon of surface facet formation during ion implantation has captured considerable scientific and technological interest. Surface facets-including wavy, pyramidal, and terraced morphologies-are typically formed during off-normal keV and MeV ion beam implantation, and due to injected gas effects. In certain circumstances, these features may also emerge during irradiation at normal incidence: when differential sputtering occurs in biphasic regions, when contaminants are inadvertently added as dopants, or when the experimental arrangement permits the coimplantation of metals. The formation of surface nanopatterns in nanocrystalline nickel under high-temperature ion irradiation at normal incidence has been observed-a phenomenon that conventional mechanisms fail to explain. A novel mechanism driving nanopattern formation under these conditions is presented. These findings offer compelling evidence that facets result from voids forming on the surface and in its vicinity. A strong correlation between the crystallographic orientation and the facet type has also been identified. Specifically, grains oriented in the <100> and <111> directions display smooth and wavy morphologies, while grains with orientations in between exhibit more complex shapes. The research indicates that grains with low stress and surface energies tend to exhibit wavy facets, while higher values lead to the formation of more complex shapes.

Unlike 2D frameworks where conductivity is largely confined to in-plane transport, the scu topology offers 3D conduction pathways that enhance bulk charge mobility. When integrated with redox-active species like tetrathiafulvalene (TTF), the scu architecture promotes electron transfer across the 3D network, enabling tunable conductivity. This article presents the construction of a 3-periodic (4,8)-c covalent organic framework (COF), TU-48, adopting a twofold interpenetrated scu net, achieved through the integration of a tetratopic D _2h-symmetric rectangular TTF structural motif and an octatopic D _2h-symmetric quadrangular prism linker. TU-48 exhibits high structural order, well-defined porosity, and redox-responsive electrochemical behavior. The high-connectivity 3D COF configuration ensures effective access to TTF redox centers, enabling controlled iodine oxidation and resulting in electrical conductivities of 4.3 × 10^-6 S cm^-1 at 298 K and 1.8 × 10^-4 S cm^-1 at 393 K. By demonstrating how enhanced structural connectivity in TTF-bridged 3D covalent lattices enables improved charge-transport properties, this research fuels innovation in sustainable energy storage solutions and electronics.

Despite advances in treatment and therapeutic strategies, patients with brain tumors, including glioblastoma (GBM) and meningioma, still face high rates of recurrence, morbidity, and mortality. Nonviral biodegradable nanoparticles are advanced materials with the potential to reprogram brain tumor cells and the tumor immune microenvironment. Localized delivery of poly(beta-amino ester) nanoparticles encapsulating immunostimulatory genes is utilized to reprogram brain tumor cells into tumor-associated antigen-presenting cells (tAPCs) by inducing overexpression of costimulatory 4-1BBL on the surface of brain tumor cells and IL-12 secreted into the tumor microenvironment. In both a humanized mouse model using human meningioma (IOMM-Lee) and an immunocompetent syngeneic orthotopic model using mouse GBM (CT-2A), delivery of 4-1BBL/IL-12 DNA-loaded nanoparticles results in reduced tumor growth, as well as complete tumor regression and long-term survival in some animals. The 4-1BBL/IL-12 gene delivery platform is an antigen-agnostic, off-the-shelf biotechnology that can successfully activate cytotoxic T-cells in tumors, improve tumor infiltration by immune cells, and enhance antitumor responses to otherwise refractory brain tumors. This nanoparticle reprogramming approach can lead to safe, long-lasting endogenous cellular immune responses that specifically target multiple types of brain tumors that exhibit antigen heterogeneity in a patient-accessible manner without using viruses or ex vivo cellular manufacturing.

Vesicular nanocarriers, such as niosomes, are versatile systems for delivering therapeutic agents, including small molecules, proteins, enzymes, nucleic acids, and other biologics. Herein, the encapsulation of bacteriophages within niosomes is investigated, expanding the conventional application of these carriers. Formulations are prepared with varying concentrations of stearylamine, a cationic cosurfactant, to assess the interactions between phages and vesicular membranes. They are characterized by dynamic light scattering, zeta potential analysis, and viral titration, providing insights into vesicle stability and phage encapsulation efficiency. Based on the characterization analysis, an optimal concentration of stearylamine is determined for successful phage encapsulation, as confirmed by cryo-electron microscopy. The stability and activity of encapsulated phages are further evaluated through pH stability tests and in vitro kinetic assays. These findings demonstrate the potential of niosomes as effective carriers for bacteriophage delivery and highlight their broader applicability for encapsulating other unconventional or sensitive therapeutic agents, offering a promising strategy for antibacterial applications.

Exposure to microgravity and cosmic radiation during spaceflight is responsible for oxidative stress onset, contributing to neuronal dysfunction and degeneration. The central nervous system is particularly vulnerable to redox imbalance and requires effective countermeasures to ensure astronaut health and performance on long-duration missions. In this study, the neuroprotective properties of polydopamine nanoparticles (PDNPs), known for their antioxidant activity, are investigated on neuron-like cells exposed to different gravitational and radiation regimes. Culture conditions included administration of PDNPs and permanence aboard the International Space Station (ISS) or on a random positioning machine. Transcriptomic analyses are conducted to assess gene expression alterations associated with oxidative stress, nuclear and mitochondrial integrity, and dopamine metabolism. In-flight, PDNP treatment mitigates the transcriptional changes induced by space stressors, preserving neuronal homeostasis. Notably, expression of key antioxidant defense genes, mitochondrial function markers and dopamine metabolism genes is stabilized in PDNP-treated neurons. This study provides preliminary evidence on the efficacy of PDNPs in protecting neuronal cells from the combined stressors associated with spaceflight: these findings suggest PDNPs as a promising countermeasure for space-induced neurodegeneration and support their potential translational application in the treatment of oxidative stress-related neurodegenerative pathologies on Earth.

Poor tumor targeting, strong toxic side effects, and high drug resistance remain clinical challenges for conventional chemotherapy. Here, it is reported that drug-cocktail core@shell nanocarriers are developed for the codelivery of lipophilic irinotecan (ITC) and the hydrophilic 5-fluorouracil (5-FU) metabolite (FdUMP), a commonly used combination in chemotherapy regimens for colorectal cancer. With a drug loading of 57% by mass, these nanocarriers achieve one of the highest reported drug payloads for a chemotherapeutic drug cocktail. Crucially, using a probe-based imaging strategy with mechanistically responsive fluorescent reporters, we found that after slow uptake predominantly via macropinocytosis, the nanocarriers rapidly traffic to endolysosomal compartments, where the acidic environment triggers sustained drug release. In alignment with the slow uptake and trafficking behavior, these nanocarriers induce a delayed yet prolonged cytotoxic effect in colorectal cancer cells. These findings provide the first direct evidence linking slow uptake, intracellular trafficking, and progressive nuclear delivery of nanocarrier cargo to the delayed yet sustained cytotoxic response. Together, this work highlights both the therapeutic potential of these nanocarriers and the broad applicability of the probe-based imaging approach to elucidate the mechanistic intracellular trafficking and nuclear delivery of different types of nanoparticles delivering cargoes beyond cancer chemotherapy in various cellular models.

Design of nanostructured electrocatalysts is essential to improve the efficiency for driving the oxygen evolution reaction (OER) at low overpotentials. Mesoporous cobalt-based thin films are prepared by dip-coating and soft-templating using the structure-directing diblock copolymer poly(ethylene-co-butylene)-block-poly(ethylene oxide). Our temperature-dependent study reveals how the calcination temperature affects the phase formation and development of the surface and bulk morphology of the catalysts. The crystallographic structure, surface composition, and development of the mesoporous framework were correlated with the OER activities. The increase in calcination temperature significantly impacts the nanoarchitecture, changing from an amorphous and dense structure, which is composed of Co(OH)₂, to structurally intact and ordered mesoporous Co₃O₄ networks. The morphology of the mesoporous network (providing accessibility for the electrolyte), the overall surface area, and the presence of a nanocrystalline Co(OH)₂ pre-catalyst phase (allowing fast formation of electrocatalytically active species), collectively determine the OER activity. These structure-property relationships explain why Co(OH)₂ films annealed at 250 °C show the lowest overpotential of 370 mV at 10 mA cm^-2 and electrochemical stability in alkaline media. The development of the ordered mesoporous architectures in dependence on the annealing temperature demonstrates the importance of careful tailoring of the synthesis conditions to achieve optimized OER performance.

Ionizable lipid nanoparticles (LNPs) are a proven means of delivering nucleic acid-based therapeutics. This project aims to expand the LNP platform for the delivery of immunostimulatory polyinosinic-polycytidylic acid (pIpC). It is demonstrated that pIpC could be successfully incorporated into LNPs with minimal modification to existing protocols. LNPs encapsulating pIpC (pIpC-LNPs) exhibit a spherical shape with a diameter under 200 nm. When administered intratumorally, pIpC-LNPs are significantly more potent than the soluble adjuvant, resulting in complete remission in 25% of tumors. To identify potential synergistic targets, T cell activation markers are screened following pIpC-LNP treatment. OX40 and CD27 are strongly upregulated and associated with intratumoral pIpC-LNP administration. Furthermore, direct treatment of a cancer cell line with pIpC-LNPs results in upregulation of the immunosuppressive PDL1. To develop a comprehensive RNA-based immunotherapeutic strategy, LNPs are formulated with mRNAs encoding CD70 (the CD27 ligand) and OX40L, or with siRNA targeting PDL1, and are evaluated in combination. Tumor growth reduction is observed when pIpC-LNPs are combined with siPDL1. This study demonstrates the potential of a triplet RNA platform-comprising immunostimulatory RNA, mRNA, and siRNA, delivered via a single versatile LNP. The data support development of pIpC-LNPs as potent intratumoral therapeutics and highlight several potential synergistic targets.

Controllable thermal storage has emerged as a central theme in advanced energy management, where external stimuli such as light, stress, and pressure can be exploited to precisely regulate heat release. Yet, realizing efficient and practical deployment requires the development of simpler noncontact actuation methods and the enhancement of heat-transfer efficiency, both of which remain major challenges. Herein, a magneto-responsive phase-change composite is presented by integrating a supercooled plastic crystal, 2-amino-2-methyl-1,3-propanediol (AMP), with dispersed NdFeB particles. This design enables noncontact triggering of supercooled phase transitions under ultralow magnetic fields as small as ≈0.04 T. Meanwhile, the dispersed magnetic particles enhance thermal conduction and promote synchronous multipoint crystallization, thereby markedly accelerating heat release. The optimized 20% AMP/NdFeB composite achieves a colossal entropy change of 507.6 J kg^-1 K^-1, a corresponding enthalpy change of 181.1 J g^-1, and a rapid temperature rise of 47.6 K, substantially outperforming leading magnetocaloric systems under far milder field conditions. This work establishes a transformative and generalizable route to noncontact, high-efficiency, and controllable thermal batteries, paving the way for their practical deployment in advanced energy systems.