Search Results (364)

Conventional anticorrosive coatings suffer from limitations of low solid content and rigorous surface pretreatment, posing environmental and cost challenges in field applications. In this study, a novel high-solid-content (>95%) epoxy-polysiloxane (Ep-PSA) ceramic metal coating was prepared that enables low-surface-treatment application. The originality lies in the synergistic combination of nano-sized ceramic powders, high-strength metallic powders, polysiloxane resin (PSA), and solvent-free epoxy resin (Ep), which polymerize through an organic–inorganic interpenetrating network to form a dense shielding layer. The as-prepared Ep-PSA coating system chemically bonds with indigenous metal substrate via Zn₃(PO₄)₂ and resin functionalities during curing, forming a conversion layer that reduces surface preparation requirements. Differentiating from existing high-solid coatings, this approach achieves superior long-term barrier properties, evidenced by |Z|_0.01Hz value of 9.64 × 10⁸ Ω·cm², after 6000 h salt spray exposure—four orders of magnitude higher than commercial 60% epoxy zinc-rich coatings (2.26 × 10⁴ Ω·cm², 3000 h salt spray exposure). The coating exhibits excellent adhesion (14.28 MPa) to standard sandblasted steel plates. This environmentally friendly, durable, and easily applicable composite coating demonstrates significant field application value for large-scale energy infrastructure. Full article

Background/Objectives: Glioblastoma (GBM) remains the most aggressive primary brain tumor in adults, with limited therapeutic options and poor prognosis despite maximal surgery, radiotherapy, and chemotherapy. The complex and immunosuppressive tumor microenvironment, pronounced intratumoral heterogeneity, and the presence of the blood–brain barrier (BBB) severely restrict the efficacy of conventional and emerging therapies. In this context, cell-based strategies leveraging macrophages, mesenchymal stromal cells (MSCs), and their derivatives have gained attention as “cellular allies” capable of modulating the GBM microenvironment and acting as targeted delivery platforms. Methods: This review systematically analyzes preclinical and early clinical literature on macrophage- and MSC-based therapeutic strategies in GBM, including engineered cells, extracellular vesicles (EVs), membrane-coated nanoparticles, and hybrid biomimetic systems. Studies were selected based on relevance to GBM biology, delivery across or bypass of the BBB, microenvironmental modulation, and translational potential. Evidence from in vitro models, orthotopic and syngeneic in vivo models, and available clinical trials was critically evaluated, with emphasis on efficacy endpoints, biodistribution, safety, and manufacturing considerations. Results: The reviewed evidence demonstrates that macrophages and MSCs can function as active therapeutic agents or delivery vehicles, enabling localized oncolysis, immune reprogramming, stromal and vascular remodeling, and enhanced delivery of viral, genetic, and nanotherapeutic payloads. EVs and membrane-based biomimetic platforms further extend these capabilities while reducing cellular risks. However, therapeutic efficacy is highly context-dependent, influenced by tumor heterogeneity, BBB integrity, delivery route, and microenvironmental dynamics. Clinical translation remains limited, with most approaches at preclinical or early-phase clinical stages. Conclusions: Cell-based and cell-derived platforms represent a promising but still evolving therapeutic paradigm for GBM. Their successful translation will require rigorous biomarker-driven patient selection, improved models that capture invasive GBM biology, scalable GMP-compliant manufacturing, and rational combination strategies to overcome adaptive resistance mechanisms. Full article

The development of functional polymer films on porous paper substrates is inherently constrained by substrate-induced defects that hinder film continuity and barrier performance. In this study, process-controlled amylose–Poly(Vinyl alcohol) (PVA) coatings incorporating ZnO nanoparticles (ZnO NPs) were fabricated via aqueous deposition to investigate the process-structure-property relationship governing oxygen barrier behavior on paper. The moisture resistance of the coating was also evaluated. Single-layer coatings exhibited severe barrier failure due to insufficient film formation and pervasive pinhole defects. In contrast, systematic multi-layer deposition enabled the formation of continuous polymer films. A pronounced non-linear reduction in oxygen transmission rate was observed once the dry coating thickness exceeded approximately 5 µm. Under these conditions, the oxygen transmission rate decreased to approximately 15 cc/m²·day·atm at 20 °C and 65% relative humidity. This transition was correlated with the elimination of substrate-induced defects, as confirmed by morphological analysis. In addition to enhanced barrier performance, ZnO NP-loaded coatings demonstrated strong and broad-spectrum antimicrobial activity against both Escherichia coli and Staphylococcus aureus, indicating their multifunctional potential for active packaging applications. Supporting evaluations further indicated adequate mechanical flexibility and high repulpability, highlighting the suitability of the coating for sustainable paper-based packaging. Overall, this work identifies a quantitative critical film thickness that serves as process-specific design guideline for engineering high-performance functional polymer coatings on porous paper substrates. Full article

Corrosion in harsh environments causes global economic losses exceeding 3 trillion US dollars annually. Traditional silicone epoxy (SE) coatings are prone to failure due to insufficient physical barrier properties and lack of active protection. In this study, cerium dioxide (CeO₂) was in situ grown on the surface of hexagonal boron nitride (h-BN) mediated by polydopamine (PDA) to prepare BN-PDA-CeO₂ ternary nanocomposites, which were then incorporated into SE coatings to construct a multi-scale synergistic corrosion protection system. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) confirmed the successful preparation of the composites, where PDA inhibited the agglomeration of h-BN and CeO₂ was uniformly loaded. Electrochemical tests showed that the corrosion inhibition efficiency of the extract of this composite for 2024 aluminum alloy reached 99.96%. After immersing the composite coating in 3.5 wt% NaCl solution for 120 days, the coating resistance (Rc) and charge transfer resistance (Rct) reached 8.5 × 10⁹ Ω·cm² and 1.2 × 10¹⁰ Ω·cm², respectively, which were much higher than those of pure SE coatings and coatings filled with single/binary fillers. Density functional theory (DFT) calculations revealed the synergistic mechanisms: PDA enhanced interfacial dispersion (adsorption energy of −0.58 eV), CeO₂ captured Cl⁻ (adsorption energy of −4.22 eV), and Ce³⁺ formed a passive film. This study provides key technical and theoretical support for the design of long-term corrosion protection coatings in harsh environments such as marine and petrochemical industries. Full article

Metal–organic frameworks (MOFs) and porous organic frameworks (POFs) have been extensively explored in recent years as lubricant additives for various systems due to their structural designability, pore storage capacity, and tunable surface chemistry. These materials are utilized to construct low-friction, low-wear interfaces and investigate the potential for superlubricity. This paper systematically reviews the tribological behavior and key mechanisms of MOFs/POFs in oil-based, water-based, and solid coating systems. In oil-based systems, MOFs/POFs primarily achieve friction reduction and wear resistance through third-body particles, layer slip, and synergistic friction-induced chemical/physical transfer films. However, limitations in achieving superlubricity stem from the multi-component heterogeneity of boundary films and the dynamic evolution of shear planes. In water-based systems, MOFs/POFs leverage hydrophilic functional groups to induce hydration layers, promote polymer thickening, and soften gels through interfacial anchoring. Under specific conditions, a few cases exhibit superlubricity with coefficients of friction entering the 10⁻³ range. In solid coating systems, two-dimensional MOFs/COFs with controllable orientation leverage interlayer weak interactions and incommensurate interfaces to reduce potential barriers, achieving structural superlubricity at the 10⁻³–10⁻⁴ level on the micro- and nano-scales. However, at the engineering scale, factors such as roughness, contamination, and discontinuities in the lubricating film still constrain performance, leading to amplified energy dissipation and degradation. Finally, this paper discusses key challenges in achieving superlubricity with MOFs/POFs and proposes future research directions, including the design of shear-plane structures. Full article

Double-shell ZnO/Al₂O₃ submicron hollow fibers were successfully fabricated through a combined electrospinning and atomic layer deposition (ALD) approach. Polyvinyl alcohol (PVA) fibers were first produced by electrospinning and subsequently coated with a conformal Al₂O₃ barrier layer via low-temperature ALD employing trimethylaluminum (TMA) and deionized (DI) H₂O to preserve the integrity of the temperature-sensitive polymer core. The inner polymer was then removed using two different techniques—thermal annealing and water dissolution—to compare their effects on the fiber morphology. Finally, a functional ZnO layer was deposited by thermal ALD with diethylzinc (DEZ) and DI H₂O. It was found that the polymer removal method critically determined the final structural and morphological characteristics of the fibers. Thermal annealing resulted in smooth, shrunken fibers, while water dissolution led to diameter expansion and the formation of a highly rough, bubble-like surface structure due to swelling-induced micro-cracking. The selection of the polymer removal method offers a precise and controllable route for tailoring the fiber morphology. The resulting high-aspect-ratio (HAR) structures, particularly the rough and expanded fibers, exhibit enhanced specific surface area, making them highly promising for applications in sensing, catalysis, and filtration. Full article

Fresh fruits are inherently prone to postharvest deterioration due to loss of moisture, respiration, mechanical damage, and microbial decay, making quality preservation a persistent challenge across fresh fruit supply chains. While conventional plastic packaging offers barrier protection and cost-efficiency, its environmental footprint, particularly poor biodegradability and increasing incidence of plastic waste necessitates a transition toward more sustainable alternatives. Among these, the use of edible coatings, primarily based on natural biopolymers, have emerged as a versatile strategy capable of modulating transpiration, gas exchange, microbial activity, and sensory quality while addressing environmental concerns. Unlike biodegradable plastic films, edible coatings directly interface with the fruit surface and offer multifunctional roles extending beyond passive protection. This review synthesizes recent advances in edible coatings for fresh fruits, with emphasis on material classes, functional performance, optimization strategies, and analytical evaluation methods. Key findings indicate that polysaccharide-based coatings provide adequate gas permeability but limited moisture resistance, while nanocomposite and multi-component systems enhance water-vapor barrier performance without compromising respiration compatibility. Incorporation of bioactive agents such as essential oils, nanoparticles, and plant extracts further extends shelf life through antimicrobial and antioxidant mechanisms, though formulation trade-offs and sensory constraints persist. The review also highlights critical limitations, including variability in barrier and mechanical properties, challenges in industrial-scale application, insufficient long-term validation under commercial cold-chain conditions, and regulatory uncertainty for active formulations. Future research priorities are identified, including mechanistic transport–physiology integration, standardized performance metrics, scalable application technologies, and life-cycle-informed material design. Addressing these gaps is essential for transitioning edible coatings from experimental sustainability concepts to robust, function-driven solutions for fresh-fruit preservation. Full article

Repairing bone defects with implants is an important topic in the field of regenerative medicine, but bacterial infection presents a significant barrier in clinical practice. Therefore, bone implants with antibacterial functionality are currently in high demand. Fresh seaweed-derived exosomes (EXOs) exhibited promising antibacterial activity against bacteria, indicating their potential as natural antimicrobial agents. Moreover, equipping the exosomal lipid bilayer with bacteria-targeting aptamers (Apt), termed EXOs-Apt, enabled precise bacterial killing, thereby promoting more effective antibacterial functions. In our design, porous polyetheretherketone (PEEK) scaffolds were 3D-printed using the melt deposition manufacturing process. Subsequently, the scaffold surfaces were modified via dopamine self-polymerization, resulting in the formation of a polydopamine (PDA) coating. Then, EXOs-Apt was applied to functionalize PEEK scaffolds with antibacterial activity. Given that EXOs display bactericidal effects while Apt facilitates bacterial capture, we engineered a surface coating platform that incorporates both components to produce a multifunctional scaffold with synergistic antibacterial activity. The results showed that modifying EXOs-Apt on PEEK scaffolds significantly improved their antibacterial performance against Escherichia coli and Staphylococcus aureus. To our knowledge, this is the first study to use EXOs-Apt as antibacterial coatings modified on PEEK scaffolds. This study provides new strategies and ideas for the development of antibacterial PEEK orthopedic implants with promising clinical value for infection-resistant repair of bone defects. Full article

Peripheral nerve injuries often recover poorly. Hyaluronic acid (HA) biomaterials, with regenerative and anti-fibrotic properties, may augment repair. We performed a PRISMA-guided systematic review of PubMed, Scopus, Web of Science, and Embase (January 2000–August 2024), capturing in vitro, in vivo, and clinical investigations of HA in peripheral nerve repair; data on study context, interventions, and outcomes were extracted. Screening and extraction were performed in duplicate. Forty-eight studies met inclusion criteria. Across in vitro and in vivo models, HA-based biomaterials consistently reduced perineural fibrosis, enhanced axonal regeneration, and improved SFI, CMAP, and NCV compared with conventional repair. Several HA hydrogels and composite conduits achieved functional outcomes approaching autografts, particularly when combined with exosomes, neurotrophic factors, or mechanobiologically tuned scaffolds. Early clinical studies demonstrated safety but remain limited by size and short follow-up. Overall, HA-containing biomaterials appear anti-fibrotic, neuroprotective, and pro-regenerative, supporting their promise as adjuncts for peripheral nerve reconstruction. For this to translate into clinical practice, future work should standardize formulations and dosing, employ rigorous, clinically relevant animal models with long-term endpoints, and advance well-powered, controlled trials to test effectiveness and durability in patients. Clinically, HA platforms show promise as anti-adhesion barriers after neurolysis and as biofunctional fillers/coatings for nerve conduits, but standardized formulations and adequately powered trials are needed to define indications and dosing. Full article

Functionalized edible coatings represent a promising strategy to mitigate postharvest losses in fresh and fresh-cut fruits. This study developed a novel, ternary active coating by integrating pectin with a cationic antimicrobial polypeptide (ε-polylysine) and a hydrophobic plant flavonoid (luteolin). The resulting composite film demonstrated transformative improvements in hydrophobicity, antioxidant, and antimicrobial activities as compared with conventional pectin-based films. Specially, the ternary composite film exhibited enhanced barrier performance, reducing water vapor, oxygen and carbon dioxide permeability by 49.1%, 68.6%, and 26.5%, respectively. When applied to fresh-cut apples, the coating effectively suppressed the browning and microbial proliferation while maintaining the hardness, total phenols and flavonoids, total soluble solids, and titratable acids over a 12-day refrigerated storage period. Comprehensive characterization via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and molecular docking simulations revealed that these superior functionalities originate from synergistic electrostatic interactions and hydrogen-bonding networks within the ternary matrix. This work provides a practical strategy for designing high-performance, plant-based coatings to reduce food waste and improve the quality of fresh-cut produce. Full article

The development of biohybrid micro-robots represents a groundbreaking advancement in targeted drug delivery for cancer therapy, offering unprecedented precision and reduced systemic toxicity. These microscale robots integrate synthetic materials with biological components such as bacteria, algae, red blood cells, or spermatozoa, capitalizing on the inherent motility, biocompatibility, and targeting capabilities of living organisms. This hybridization enables active navigation through complex biological environments, overcoming physiological barriers such as the blood–brain and endothelial junctions that impede traditional nanoparticle-based systems. In this study, we propose a multi-functional biohybrid micro-robotic platform composed of magnetically actuated synthetic chassis coated with doxorubicin-loaded lipid vesicles and tethered to Magnetospirillum magneticum for propulsion and tumor-homing capabilities. The results underscore the promise of biohybrid micro-robots as intelligent, minimally invasive agents for next-generation oncological therapies, capable of delivering chemotherapeutics with enhanced spatial and temporal accuracy. Future work will focus on clinical translation pathways, biosafety evaluations, and scalability of production under Good Manufacturing Practice (GMP) standards. Full article

The coagulation cascade triggered by the contact between blood and the surface of implantable/interventional devices can lead to thrombosis, severely compromising the long-term safety and efficacy of medical devices. As an alternative to systemic anticoagulants, surface anticoagulant modification technology can achieve safer hemocompatibility on the device surface, holding significant potential for clinical application. This article systematically elaborates on the latest research progress in the surface anticoagulant modification of blood-contacting materials. It analyzes and discusses the main strategies and their evolution, spanning from physically inert carbon-based coatings and heparin-based drug-functionalized surfaces to hydrophilic/hydrophobic dynamic physical barriers, biologically signaling regulatory coatings, and bio-integrative/regenerative endothelium-mimicking surfaces. The advantages and limitations of the respective methods are outlined, and the potential for synergistic application of multiple strategies is explored. A special emphasis is placed on current research hotspots regarding novel anticoagulant surface technologies, such as hydrogel coatings, liquid-infused surfaces, and 3D-printed endothelialization, aiming to provide insights and references for developing long-term, safe, and hemocompatible cardiovascular implantable devices. Full article

Cnidium monnieri is a valuable functional plant with significant potential for green pest control. However, its large-scale application is limited by its low and uneven seed germination in fields. To determine the factors that affect the germination of C. monnieri seeds, we examined its seed viability, germination percentage and germination speed index (GSI) after seed-coat treatments, water permeability, and the types and activity of endogenous inhibitory substances in C. monnieri seeds. The results indicated that the seed viability of C. monnieri is 95%, but the germination percentage was relatively low (12.60%). Seed coat removal significantly enhanced both the germination percentage and the GSI, but had no significant effect on water absorption rate. Moreover, ethyl acetate extracts completely inhibited the seed germination of the control non-dormant Brassica rapa subsp. rapa, while diethyl ether extracts showed moderate suppression, and petroleum ether extracts exhibited the weakest effect. And the three endogenous inhibitory substances, i.e., dibutyl phthalate, 2,6-di-tert-butylphenol, and 2,4-di-tert-butylphenol significantly reduced the seed germination, seedling height and root length of B. rapa, indicating their high inhibitory efficiency on seed germination. Our study demonstrates that the mechanical barrier of the seed coat and the presence of potent endogenous germination inhibitory substances are the key factors influencing the germination of C. monnieri seeds. These findings provide a theoretical basis for promoting seed germination of C. monnieri, which enhance its application value as functional plant for green pest control. Full article

Bone is a structurally complex and dynamic tissue that plays a crucial role in mobility and skeletal stability. However, conditions such as osteoporosis, osteoarthritis, trauma-induced fractures, infections, and malignancies often necessitate the use of orthopedic and dental implants. Despite significant progress in implant biomaterials, challenges such as bacterial infection, inflammation, and loosening continue to compromise implant longevity, frequently leading to revision surgeries and extended recovery times. Smart coatings have emerged as a next-generation solution to these problems by providing on-demand, localized therapeutic responses to microenvironmental changes around implants and promoting bone regeneration. Such coatings can minimize antibiotic resistance by enabling controlled, stimulus-triggered drug release. Although the idea of using pH-sensitivity as a tool to make smart coatings is not a new thought, there are no options currently good enough to enter clinical studies. This review provides a comprehensive overview of recent advances in pH-sensitive polymers, hybrid composites, porous architectures, and bioactive linkers designed to dynamically respond to pathological pH variations at implant sites. By investigating the mechanisms of action, antibacterial and anti-inflammatory effects, and roles in bone regeneration, it is shown that the ability to provide time-dependent drug release for both short-term and long-term infections, as well as keeping the environment welcoming to the bone cell growth and replacement, is not an easy goal to reach, even with a fully biocompatable, non-toxic, and semi-biodegradable (one that releases the drug, but does not fade away) coating material compound. Reviewing all available options, including their functions and failures, finally, emerging trends, translational barriers, and future opportunities for clinical implementation are highlighted, underscoring the transformative potential of bioresponsive coatings in orthopedic and dental implant technologies. Full article

Conventional petroleum-based protective coatings release high levels of volatile organic compounds (VOCs) and contribute to resource depletion, urging the development of environmentally responsible alternatives. Among the bio-based candidates, microalgae and Cyanobacteriophyta have recently gained attention for their ability to produce diverse biopolymers and pigments with intrinsic protective functionalities. However, existing literature has focused mainly on algal biofuels and general biopolymers, leaving a major gap in understanding their application as sustainable coating materials. This review addresses that gap by providing the first integrated assessment of algae-based protective coatings. It begins by defining abiotic and biotic surface degradation mechanisms, including microbiologically influenced corrosion, to establish performance benchmarks. The review then synthesizes recent findings on key algal components, including alginate, extracellular polymeric substances (EPS), and phycocyanin, linking biochemical composition to functional performance, techno-economic feasibility, and industrial scalability. It evaluates their roles in adhesion strength, UV stability, corrosion resistance, and antifouling activity. Reported performance metrics include adhesion strengths of 2.5–3.8 MPa, UV retention above 85% after 2000 h, and corrosion rate reductions of up to 40% compared with polyurethane systems. Furthermore, this study introduces the concept of carbon-negative, multifunctional coatings that simultaneously protect infrastructure and mitigate environmental impacts through CO₂ sequestration and pollutant degradation. Challenges involving biomass variability, processing costs (>USD 500/ton), and regulatory barriers are critically discussed, with proposed solutions through hybrid cultivation and biorefinery integration. By bridging materials science, environmental engineering, and sustainability frameworks, this review establishes a foundation for transforming algae-based coatings from laboratory research to scalable, industrially viable technologies. Full article