Search Results (1,186)

Surface-enhanced Raman spectroscopy (SERS) enables ultra-sensitive molecular detection and has broad analytical and biomedical applications; recent advances focus on high-performance substrates and innovative detection strategies. However, achieving controllable and reproducible substrate fabrication—particularly using natural templates such as hair—remains challenging, limiting SERS application in trace analysis and on-site detection. This study developed a single-hair in situ SERS platform using a natural hair template. Confinement within hair cuticle grooves and capillary-evaporation assembly enables dense arrangement of cetyltrimethylammonium bromide-coated Au nanorods and polyvinylpyrrolidone-coated Au nanoparticles, forming uniform plasmonic nanoarrays. Spectroscopy and microscopy analyses confirmed the regular alignment of nanostructures along the hair axis with denser packing at the edges. The platform detected crystal violet at 10⁻⁹ M, yielding clear signals, negligible background, and stable peaks after repeated washing. For p-phenylenediamine, enhancement was observed down to 10⁻⁶ M. On the platform, a concentration-dependent response appeared within 10⁻³–10⁻⁵ M, with spatial Raman imaging along the hair axis. Capillary-evaporation coupling and interfacial wettability facilitated solute enrichment from larger to smaller gap hotspots, improving signal-to-noise ratio and reproducibility. This portable, low-cost, and scalable method supports rapid on-site screening in complex matrixes, offering a general strategy for hotspot engineering and programmable assembly on natural templates. Full article

Zirconium (Zr) thin films were deposited on silicon (Si) substrates via pulsed laser deposition (PLD) using a 248 nm excimer laser. The effects of substrate temperature on film morphology and crystallinity were systematically investigated. X-ray diffraction (XRD) revealed that the Zr(100) plane exhibited the strongest orientation at 400 °C while Zr (002) was maximum at 500 °C. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses demonstrated an increase in surface roughness with temperature, with the smoothest surface observed at lower temperatures and significant island formation at 500 °C due to the transition to 3D growth. At 500 °C, interdiffusion effects led to the formation of zirconium silicide at the Zr/Si interface. To further interpret the experimental findings, computational modeling was employed to analyze the transition from 2D layer-by-layer growth to 3D island formation at elevated temperatures. Using a multi-parameter kinetics-free model based on free energy minimization, the critical film thickness for this transition was determined to be ~1–2 nm, aligning well with experimental observations. A separate kinetic model of island nucleation and growth predicts that this shift is driven by the kinetics of adatom surface diffusion. Additionally, the kinetic simulations revealed that, at 400 °C, adatom diffusivity optimally balances crystallization and surface energy minimization, yielding the highest film quality. At 500 °C, the rapid increase in diffusivity leads to the proliferation of 3D islands, consistent with the roughness trends observed in SEM and AFM data. These findings underscore the critical role of deposition parameters in tailoring Zr thin films for applications in advanced coatings and electronic devices. Full article

Metal–organic frameworks (MOFs) are a class of highly ordered nanoporous crystals that possess a designable framework and unique chemical versatility. MOF thin films are ideal for nanotechnology-enabling applications, such as optoelectronics, catalytic coatings, and sensing. Mg-MOF-74 has been drawing increasing attention due to its remarkable CO₂ uptake capacity among MOFs and other commonly used CO₂ absorbents. Mg-MOF-74 thin films are currently fabricated by immersing selected substrates in precursor solutions, followed by a traditional solvothermal synthesis process. Herein, we introduce a rapid, easy, and cost-effective synthesis protocol to fabricate MOF thin films in an additive manner. In this work, the controllable synthesis of Mg-MOF-74 thin films directly on optical supports is reported for the first time. Dense, continuous, and uniform Mg-MOF-74 thin films are successfully fabricated on bare glass slides, with an average growth rate of up to 85.3 nm min⁻¹. The structural and optical properties of the resulting Mg-MOF-74 thin films are characterized using X-ray diffraction, atomic force microscopy, scanning electron microscopy, UV-Vis-NIR spectroscopy, and Fourier Transform Infrared Spectroscopy (FTIR). The CO₂ adsorption performance of the resulting Mg-MOF-74 thin films is studied using FTIR for the first time, which demonstrates that, as per the length of the light path for gas absorption, 1 nm Mg-MOF-74 thin film could provide 400.9 ± 18.0 nm absorption length for CO₂, which is achieved via the extraordinary CO₂ adsorption by Mg-MOF-74. The synthesis protocol enables the rapid synthesis of MOF thin films, highlighting Mg-MOF-74 in more CO₂-related applications, such as enhanced CO₂ adsorption and MOF-enhanced infrared gas sensing. Full article

Wetting behavior of molten metals on solid substrates is a critical phenomenon influencing numerous industrial applications, including welding, anti-corrosion coatings, and metal additive manufacturing (AM). In particular, molten metal jetting (MMJ), an emerging AM technology, requires that the molten metal remain pinned at the nozzle exit. Thus, each new metal requires a specific nozzle material to ensure consistent droplet ejection and deposition, making it important to rapidly identify the appropriate wetting combinations. However, traditional measurements of wetting angles require expensive equipment and only allow one combination of materials to be investigated at a time which can be time consuming. This work introduces a rapid screening method based on sessile droplet experiments to evaluate wetting profiles across multiple metal–substrate combinations simultaneously. This study investigates the wetting interactions of molten Al alloy (Al4008), Cu, and Sn on various ceramic and metal substrates to identify optimal material combinations for MMJ nozzle designs. Results demonstrate that Al4008 achieves wetting on ceramic substrates such as AlN, TiO₂, and SiC, with varying mechanisms including chemical reactions and weak surface interactions. Additionally, theoretical predictions regarding miscibility gaps and melting point differences were verified for Cu and Sn on refractory metals like Mo and W. Findings from this study contribute to the establishment of a materials compatibility library, enabling the selection of wetting/non-wetting combinations for stable MMJ operation. This resource not only advances MMJ technologies but also provides valuable insights for broader applications such as welding, coating, and printed electronics. Full article

SPCEs are crucial for electrochemical sensing because of their portability, low cost, disposability, and ease of mass production. This study details their manufacture, surface modifications, electrochemical characterization, and use in chemical and biosensing. SPCEs integrate working, reference, and counter electrodes on PVC or polyester substrates for compact sensor design. Surface modifications, such as plasma treatment (O₂, Ar), nanomaterial addition (AuNPs, GO, CNTs), polymer coatings, and MIPs, enhance performance. These changes improve sensitivity, selectivity, stability, and electron transport. Electrochemical methods such as CV, DPV, SWV, and EIS detect analytes, including biomolecules (glucose, dopamine, and pathogens) and heavy metals (Pb²⁺, As³⁺). Their applications include healthcare diagnostics, environmental monitoring, and food safety. Modified SPCEs enable rapid on-site analysis and offer strong potential to transform our understanding of the physical world. Full article

Background: Despite considerable advances to improve colorectal cancer (CRC) survival over the last decade, therapeutic challenges remain due to the rapid metastatic dissemination of primary tumors. This study revealed the apoptotic and anti-growth mechanism of VTD, a previously used anti-hypertensive supplement, can elevate UBXN2A, a known tumor suppressor protein in CRC, and simultaneously enhance intrinsic and extrinsic apoptosis in metastatic cancer cells. Methods and Results: An AOM/DSS mouse model of CRC showed that UBXN2A haplosufficient (UBXN2A +/−) mice treated with VTD had less tumor burden than mice with the full UBXN2A gene treated with vehicle. We have previously shown that casein-coated mesoporous silica nanoparticles (MSNs) offer an effective local delivery of drugs at tumor sites. Our findings demonstrate that the high rate of extracellular release of matrix metalloproteinases (MMPs), particularly MMP-7, by metastatic colon cancer cells, triggers the release of VTD from casein-coated mesoporous MSNs. This shows the “Zip Code” mechanism for the local enrichment of VTD at the tumor sites. After in vitro drug release verification, two independent mouse experiments, a xenograft and a splenolepatic metastatic mouse model of CRC, were used to evaluate the therapeutic efficacy of VTD-loaded and casein-coated carboxylated mesoporous silica nanoparticles, MSN-COOH/VTD/CAS (VTD, 0.2 mg/kg). Animal experiments revealed that MSN-COOH/VTD/CAS (VTD, 0.2 mg/kg) slows down the progress of tumors. Mass spectrometry (MS) revealed improved pharmacokinetics (PK) profile as MSN-COOH/VTD/CAS had less VTD accumulation in non-cancerous organs compared to pure VTD. We further improved nanoparticle targeting and drug release by shifting to calcium-based particles (CBPs). The engineered CBPs demonstrated higher drug-releasing performance. Without the MMPs trigger, MSNs show slow and continuous “drug leak” over longer period of time whereas CCSMPs stops leakage within an hour. Additionally, CBPs showed higher sensitivity to MMP-7 than MMP-9, enhancing the targetability of CBPs for CRC metastatic tumors with excessive extracellular MMP-7. Conclusions: This study introduces a new platform utilizing nanoparticle-based site-specific delivery of a plant-based anti-metastatic molecule, veratridine, with enhanced safety and therapeutic efficacy for the treatment of metastatic CRC. Full article

Magnesium alloy represents a typical category of biodegradable medical materials. However, the poor corrosion resistance and rapid degradation have significantly hindered the clinical adoption of magnesium alloy implants. This paper puts forward a method to improve the corrosion resistance of magnesium alloy by using an Fe-based composite coating. The microstructure and composition of the coating were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDS). The corrosion resistance was evaluated through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements conducted in simulated body fluid, while the degradation behavior of the samples was evaluated by examining the hydrogen evolution volume and corrosion morphology during immersion tests. The results indicate that the composite coating exhibits a dual-layer structure, consisting of an amorphous carbon–fluorine transition layer and an iron-rich surface layer. After coating treatment, the corrosion current density of magnesium alloy decreased from 1.38 × 10⁻⁴ to 3.41 × 10⁻⁶ A/cm². Throughout a 28-day immersion period, the composite-coated sample demonstrated a remarkably low hydrogen evolution rate and maintained a smooth, intact surface. Furthermore, hemolysis and platelet adhesion tests confirmed the outstanding blood compatibility of the composite-coated magnesium alloy, showing an ultralow hemolysis rate of 0.1% and minimal platelet adhesion with well-preserved morphology. Full article

Aflatoxin (AF) contamination in pistachios remains a critical food safety and trade challenge, given the potent carcinogenicity of AF-B₁ and the nut’s high susceptibility to Aspergillus infection throughout production and storage. Traditional decontamination methods such as roasting, irradiation, ozonation, and acid/alkaline treatments can reduce AF levels but often degrade sensory and nutritional quality, implying the need for more sustainable approaches. In recent years, innovative nonthermal interventions, including pulsed light, cold plasma, nanomaterial-based adsorbents, and bioactive coatings, have demonstrated significant potential to decrease fungal growth and AF accumulation while preserving product quality. Biosensing technologies such as electrochemical immunosensors, aptamer-based systems, and optical or imaging tools are advancing rapid, portable, and sensitive detection capabilities. Combining these experimental strategies with artificial intelligence (AI) and machine learning (ML) models can increasingly be applied to integrate spectral, sensor, and imaging data for predicting fungal development and AF risk in real time. This review brings together progress in nonthermal reduction strategies, biosensing innovations, and data-driven approaches, presenting a comprehensive perspective on emerging tools that could transform pistachio safety management and strengthen compliance with global regulatory standards. Full article

Monitoring contamination in soil and food systems remains vital for ensuring environmental and public health, particularly in agriculture-intensive regions. Existing laboratory-based techniques are often time-consuming, equipment-dependent, and impractical for rapid on-site screening. In this study, we present a portable, non-faradaic electrochemical impedance-based sensing platform capable of simultaneously detecting Salmonella Typhimurium (S. Typhi) and Aflatoxin B1 in spiked soil run-off samples. The system employs ZnO-coated electrodes functionalized with crosslinker for covalent antibody immobilization, facilitating selective, label-free detection using just 5 µL of sample. The platform achieves a detection limit of 1 CFU/mL for S. Typhi over a linear range of 10–10⁵ CFU/mL and 0.001 ng/mL for Aflatoxin B1 across a dynamic range of 0.01–40.96 ng/mL. Impedance measurements captured with a handheld potentiostat were strongly correlated with benchtop results (R² > 0.95), validating its reliability in field settings. The duplex sensor demonstrates high precision with recovery rates above 80% and coefficient of variation below 15% in spiked samples. Furthermore, machine learning classification of safe versus contaminated samples yielded an ROC-AUC > 0.8, enhancing its decision-making capability. This duplex sensing platform offers a robust, user-friendly solution for real-time environmental and food safety surveillance. Full article

A sheet-type sinter-bonding material was developed to form thermally stable and highly heat-conductive joints suitable for wide-bandgap (WBG) semiconductor dies and high-heat-flux devices, and its bonding characteristics were investigated. To enhance the cost-competitiveness of the bonding material, Ag-coated Cu (Cu@Ag) particles were employed as fillers instead of conventional Ag particles. To facilitate accelerated sintering, a bimodal particle size distribution comprising several micron- and submicron-sized particles was adopted by synthesizing and mixing both size ranges. For sheet fabrication, a decomposable resin was used as the essential binder component, which could be removed during the bonding process via thermal decomposition. This approach enabled the formation of a sintered bond line composed entirely of Cu@Ag particles. Thermogravimetric and differential thermal analyses revealed that the decomposition of the resin in the sheet occurred within the temperature range of 290–340 °C. Consequently, sinter-bonding conducted at 350 °C and 370 °C exhibited significantly superior bondability compared to bonding at 330 °C. In particular, sinter-bonding at 350 °C for just 60 s resulted in a highly densified joint microstructure with a low porosity of 7.6% and high shear strength exceeding 25 MPa. The formation of the bond line was initiated by sintering between the outer Ag shells of the adjacent particles. However, with increasing bonding time or temperature, sintering driven by Cu diffusion from the particle cores to the outer Ag shells, particularly in the submicron-sized particles, was progressively enhanced. These results obtained from the fabricated sheet-type materials demonstrate that, even with the use of resin, rapid solid-state sintering between filler particles combined with the removal of resin through decomposition enables the formation of a metallic bond line with excellent thermal conductivity. Full article

Surface pretreatment significantly influences the hygroscopic behavior of wood, which in turn affects surface stability when exposed to variable climatic conditions. This study focuses on how different surface pretreatment methods impact the performance of protective coating applied on spruce wood (Picea abies (L.) Karst.) during one year of natural weathering. Samples were prepared using various surface treatments: milling and sanding with grit sizes P40, P80, and P120, respectively. Two types of coatings were applied: a solventborne coating (ADLER Pullex Plus-Lasur) and a waterborne coating (DColor FK 47 UV Protect). The samples were exposed for 12 months at an outdoor testing site in Suchdol, Czech. Surface properties were assessed through color changes in the CIE Lab* space, gloss measurements (ISO 2813), contact angle analysis, and visual inspection. The results showed that exposure to UV radiation and microbial activities led to the gradual degradation of the optical properties and aesthetic appearance of the wood. Surfaces with greater roughness preserved their aesthetic properties more effectively, indicating a higher absorption of the coating. Untreated wood exhibited low water repellency, while the coated surface demonstrated enhanced hydrophobicity. Notably, the waterborne coating showed a temporary increase in contact angle around the sixth month, indicating surface clogging by dust particles. In contrast, the solventborne coating had a rapid decrease in wettability during the first nine months. These findings suggested the importance of surface pretreatment and coating type in maintaining the long-term performance and aesthetic appearance for wood used in exterior conditions. Full article

Biofouling on offshore wind farm substructures threatens operational reliability and raises maintenance demands, underscoring the need for effective antifouling strategies. This study presents a 27-month evaluation of fouling development on a conventional non-antifouling coating and self-polishing copolymer (SPC) systems at a South Korean offshore wind farm. Biofouling coverage was assessed through long-term image analysis, and surface energy was characterized via contact angle measurements. Species analyses identified successional communities dominated by barnacles, coralline algae, and bryozoa. The conventional coating showed rapid colonization, exceeding 90% coverage within 10 months, whereas the SPC systems exhibited superior performance by suppressing settlement, though their effectiveness declined over time. Quantitative analysis revealed a clear relationship between higher surface energy and increased fouling rates, highlighting material properties as a key factor in colonization. This study provides one of the first long-term quantitative datasets from South Korean waters, advancing understanding of biofouling dynamics and informing antifouling strategies for offshore wind infrastructure. Full article

Personalized, point-of-care testing of human tears is essential for ocular disease diagnosis, yet it is hampered by picomolar biomarker levels and microliter sample volumes. In this work, we developed an integrated, portable electrochemiluminescence (ECL)-based device for rapid and quantitative detection of tumor necrosis factor alpha (TNF-α), a pivotal inflammatory marker in ocular surface disease, with particular relevance to dry eye syndrome (DES). The device integrates a miniaturized electrochemical cell for ECL reactions and a compact silica photomultiplier for signal measurement. A vertical silica mesochannel (VSM)-coated ITO electrode is also integrated and further functionalized with TNF-α-specific aptamers. The VSM enables the enrichment of ECL luminophores, thus enabling further amplification of ECL signals and enhancing sensitivity. A wide linear range from 0.1 to 200 pg/mL was achieved using 10-fold dilution of 3 μL tear samples. Overall, this study provides a portable, highly sensitive platform for personalized analysis of TNF-α in tear fluid, enabling rapid point-of-care assessment of DES. Full article

As modern industrialization accelerates, traditional metallic materials face challenges in meeting critical surface protection requirements. Constrained by their physicochemical properties, these materials exhibit significant performance degradation. This leads to frequent peeling of surface coatings on critical components. Polyetheretherketone (PEEK) is a high-performance semi-crystalline thermoplastic used in advanced engineering applications. Its composite coating systems have emerged as a promising alternative to metallic coatings. This paper systematically reviews the recent advances in coating preparation techniques for PEEK composites. The current status of the use of mainstream preparation methods such as thermal spray technology, rapid prototyping and electrophoretic deposition is highlighted. The strengths and weaknesses of each method are also compared. Critical parameters including substrate roughness, temperature, and substrate elasticity are systematically examined. The effects of these variables are evaluated with respect to critical performance indicators, including porosity levels and interfacial bonding strength of PEEK composite coatings. A comparative investigation was carried out on different reinforcement materials. Their interfacial interactions with the matrix are examined in detail at the microscopic level. The impact of these modification strategies on coating performance was comprehensively evaluated. Full article

Increasing interest in functional nutrition has driven the incorporation of probiotics into pet food formulations to enhance digestive health, immune response, and overall well-being in companion animals. This systematic review examines scientific publications, patents, and market developments related to probiotic-enriched pet food from 2014 to 2024. We evaluate major probiotic taxa—including Lactobacillus spp., Bifidobacterium spp., Bacillus spp., and Saccharomyces cerevisiae—based on their resilience during processing, gastrointestinal survival, and documented health benefits. Delivery technologies such as microencapsulation, coating matrices, and post-processing supplementation are analyzed for their effectiveness in preserving probiotic viability within dry and wet food matrices. Patent landscape analysis highlights innovation trends in strain selection, formulation design, and processing methods. In vivo and in vitro studies demonstrate that probiotic supplementation modulates gut microbiota composition, improves fecal parameters, enhances immune markers, and promotes nutrient absorption in both canine and feline models. Market data reveal rapid expansion of commercial probiotic pet food products, yet scientific research remains limited compared to human nutrition. Overall, the findings indicate that while probiotics hold clear potential to improve gastrointestinal health and immunity in pets, evidence remains fragmented, particularly for cats and long-term outcomes. Bridging the gap between industrial innovation and controlled clinical validation will be essential for developing next-generation probiotic pet foods. Full article