Search Results (209)

Knowing the superior biochemical defense mechanisms of sessile organisms, it is not hard to believe the cure for any human sickness might be hidden in nature—we “just” have to identify it and make it safely available in the right dose to our organs and cells that are in need. For decades, green tea catechins (GTCs) have been a case in point. Because of their low redox potential and favorable positioning of hydroxyl groups, these flavonoid representatives (namely, catechin—C, epicatechin—EC, epicatechin gallate—ECG, epigallocatechin—EGC, epigallocatechin gallate—EGCG) are among the most potent plant-derived (and not only) antioxidants. The proven anti-inflammatory, neuroprotective, antimicrobial, and anticarcinogenic properties of these phytochemicals further contribute to their favorable pharmacological profile. Doubtlessly, GTCs hold the potential to “cope” with the majority of today‘s socially significant diseases, yet their mass use in clinical practice is still limited. Several factors related to the compounds’ membrane penetrability, chemical stability, and solubility overall determine their low bioavailability. Moreover, the antioxidant-to-pro-oxidant transitioning behavior of GTCs is highly conditional and, to a certain degree, unpredictable. The nanoparticulate delivery systems represent a logical approach to overcoming one or more of these therapeutic challenges. This review particularly focuses on the lipid-based nanotechnologies known to be a leading choice when it comes to drug permeation enhancement and not drug release modification nor drug stabilization solely. It is our goal to present the privileges of encapsulating green tea catechins in either vesicular or particulate lipid carriers with respect to the increasingly popular trends of advanced phytotherapy and functional nutrition. Full article

Transdermal drug delivery (TDD) is an increasingly important non-invasive method for administering active pharmaceutical ingredients (APIs) through the skin barrier, offering advantages such as improved therapeutic efficacy and reduced systemic side effects. As demand increases for patient-friendly and minimally invasive treatment options, TDD has attracted substantial attention in research and clinical practice. This review summarizes recent advances enhancing skin permeability through chemical enhancers (e.g., ethanol, fatty acids, terpenes), physical (e.g., iontophoresis, microneedles, sonophoresis), and nanotechnological methods (e.g., liposomes, ethosomes, solid lipid nanoparticles, and transferosomes). A comprehensive literature analysis, including scientific publications, regulatory guidelines, and patents, was conducted to identify innovative methods and materials used to overcome the barrier properties of the stratum corneum. Special emphasis was placed on in vitro, ex vivo, and in vivo evaluation techniques for such as Franz diffusion cells for assessing drug permeation and skin interactions. The findings highlight the importance of active physical methods, passive nanostructured systems, and chemical penetration enhancers. In conclusion, integrating multiple analytical techniques is essential for the rational design and optimization of effective transdermal drug delivery systems. Full article

Background/Objectives: The work presented herein focused on the development and characterization of a transdermal caffeine platform fabricated from ultrathin micro- and submicron fibers produced via electrospinning. Methods: The formulations incorporated caffeine encapsulated in a polyethylene oxide (PEO) matrix, combined with various permeation enhancers. A backing layer made of annealed electrospun polycaprolactone (PCL) facilitated the lamination of the two layers to form the final multilayer patch. Comprehensive characterization was conducted, utilizing scanning electron microscopy (SEM) to assess the fiber morphology, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) for chemical detection and to assess the stability of the caffeine, and differential scanning calorimetry (DSC) along with wide-angle X-ray scattering (WAXS) to analyze the physical state of the caffeine within the fibers of the active layer. Additionally, Franz cell permeation studies were performed using both synthetic membranes (Strat-M) and ex vivo human stratum corneum (SC) to evaluate and model the permeation kinetics. Results: These experiments demonstrated the significant role of enhancers in modulating the caffeine permeation rates provided by the patch, achieving permeation rates of up to 0.73 mg/cm² within 24 h. Conclusions: This work highlights the potential of using electro-hydrodynamic processing technology to develop innovative transdermal delivery systems for drugs, offering a promising strategy for enhancing efficacy and innovative therapeutic direct plasma administration. Full article

Transdermal drug delivery offers a non-invasive route for the systemic and localized administration of therapeutics; however, the skin’s barrier function limits its efficiency. This study investigates the application of various electromagnetic field (EMF) configurations to enhance the transdermal delivery of salicylic acid, a model compound with moderate lipophilicity and ionizability. Samples were exposed to pulsed, oscillating, static, and rotating magnetic fields, and their effects on physicochemical properties, thermal stability, skin permeation, and accumulation were evaluated. Structural analyses (FTIR, XRD) and thermal assessments (TGA, DSC) confirmed that EMF exposure did not alter the chemical structure or stability of salicylic acid. In vitro transdermal studies using porcine skin and Franz diffusion cells revealed that pulsed magnetic fields—especially with a 5 s on/5 s off cycle—and rotating magnetic fields at 30–50 Hz significantly enhanced drug permeation compared to controls. In contrast, static fields of negative polarity increased skin retention, suggesting their potential for controlled, localized delivery. These findings demonstrate that EMFs can be used as tunable, non-destructive tools to modulate drug transport across the skin and support their integration into transdermal delivery systems aimed at optimizing therapeutic profiles. Full article

Excessive carbon dioxide (CO₂) emissions represent a critical challenge in mitigating global warming, necessitating advanced separation technologies for efficient carbon capture. Silica-based membranes have attracted significant attention due to their exceptional chemical, thermal, and mechanical stability under harsh operating conditions. In this study, we introduce a novel layered hybrid membrane designed based on amine-functionalized silica precursors, where a distinct affinity gradient is engineered by incorporating two types of amine-functionalized materials. The top layer was composed of high-affinity amine species to maximize CO₂ sorption, while a sublayer with milder affinity facilitated smooth CO₂ diffusion, thereby establishing a continuous solubility gradient across the membrane. A dual approach, combining comprehensive experimental testing and rigorous theoretical modeling, was employed to elucidate the underlying CO₂ transport mechanisms. Our results reveal that the hierarchical structure significantly enhances the intrinsic driving force for CO₂ permeation, leading to superior separation performance compared to conventional homogeneous facilitated transport membranes. This study not only provides critical insights into the design principles of affinity gradient membranes but also demonstrates their potential for scalable, high-performance CO₂ separation in industrial applications. Full article

This study addresses the critical challenges of hydrogen permeation and embrittlement in metallic pipelines for hydrogen storage and transportation by developing an epoxy resin-based composite coating with enhanced hydrogen barrier properties. Using cold spray technology, the fabricated coatings with controlled 250–320 μm thicknesses incorporating graphene/ceramic composite particles uniformly dispersed in the epoxy matrix. Microstructural characterization revealed dense morphology and excellent interfacial bonding. Electrochemical hydrogen charging tests demonstrated remarkable hydrogen permeation reduction, showing a strong positive correlation between coating thickness and barrier performance. The optimal 320 μm-thick coating achieved a hydrogen content of only 0.28 ± 0.09 ppm, representing an 89% reduction compared to that in uncoated substrates. The superior performance originates from the Al₂O₃/SiO₂ networks providing physical barriers, graphene offering high-surface-area adsorption sites, and MgO chemically trapping hydrogen atoms. Post-charging analysis identified interfacial stress concentration and hydrogen-induced plasticization as primary causes of ceramic particle delamination. This work provides both fundamental insights and practical solutions for designing high-performance protective coatings in long-distance hydrogen pipelines. Full article

Background: A key challenge in modern pharmaceutical research is developing predictive models for drug formulation behavior. Since permeability is closely linked to molecular properties, considering a broad of characteristics is essential for building reliable predictive tools. Near-infrared spectroscopy (NIR), a non-destructive, non-invasive, and chemically specific method, offers a powerful alternative to current gold-standard methods approved by regulatory agencies. Objectives: This study aims to apply a partial analytical quality by design (AQbD) approach to enhance the understanding and development of NIR and RP-HPLC methodologies. Methods: The employment of NIR with multivariate data analysis enabled the establishment of chemometric models for the classification and quantification of bifonazole (BFZ) in cream formulations. Results: An analytical target profile (ATP) was defined to guide the selection of critical method variables and support method design and development activities. Risk assessment was carried out using an Ishikawa diagram. For the RP-HPLC method, key performance parameters such as peak area, theoretical plates, tailing factor, and assay were evaluated, while NIR spectra and BFZ concentration were considered for method performance. The quantification models enabled the accurate determination of BFZ content, yielding results of 8.48 mg via NIR and 8.34 mg via RP-HPLC, with an RSD of 1.25%. Conclusions: These findings demonstrate the robustness and reliability of the models, making them suitable for routine quality control of BFZ formulations. Future research should aim to explore its use for monitoring permeation dynamics in real time and integrating it into regulatory frameworks to standardize its application in pharmaceutical quality control and formulation development. Full article

Wood-based membranes have garnered increasing attention due to their structural advantages and durability in the efficient treatment of oily kitchen wastewater. However, conventional fabrication methods often rely on toxic chemicals or synthetic processes, generating secondary pollutants and suffering from fouling, which reduces performance and increases resource loss. In this study, an innovative bilayer membrane was developed from balsa wood by combining a hydrophilic longitudinal layer for water transport with a polydimethylsiloxane (PDMS)-impregnated carbonized transverse layer to enhance hydrophobicity, resulting in increased separation efficiency and a reduction in fouling by 98.38%. The results show a high permeation flux of 1176.86 Lm^–2 h^–1 and a separation efficiency of 98.60%, maintaining low fouling resistance (<3%) over 20 cycles. Mechanical tests revealed a tensile strength of 10.92 MPa and a fracture elongation of 10.42%, ensuring robust mechanical properties. Wettability measurements indicate a 144° contact angle and a 7° sliding angle with water on the carbonized side, and a 163.7° contact angle with oil underwater and a 5° sliding angle on the hydrophilic side, demonstrating excellent selective wettability. This study demonstrates the potential of carbonized wood-based membranes as a sustainable, effective alternative for large-scale wastewater treatment. Full article

UV radiation can change the internal molecular composition, macroscopic rheological properties, and microscopic chemical composition of asphalt. To study the effect of ultraviolet aging on asphalt and its structure–activity relationship, its rheological properties were measured by dynamic shear rheology and multiple stress recovery creep tests, its chemical compositions were measured by component composition, elemental composition, and infrared spectrum tests, and its molecular weight, distribution, and molecular structure were determined by gel permeation chromatography and nuclear magnetic resonance tests. Then, the molecular weight and molecular structure, rheological properties, and microchemical aging behavior of asphalt after UV aging were characterized by correlation analysis, and the structure–activity relationship was analyzed. The results show that the deformation resistance and elastic recovery ability of asphalt after UV aging are enhanced, and the flow performance is decreased. The ultraviolet radiation caused the aromatic hydrocarbons containing naphthenes and long alkyl chains in the asphalt to break and connect with asphaltenes with a ring structure. The asphaltene content in each bitumen sample exceeded 46%, and that in KL reached 55%, indicating that the bitumen changed into a gel structure. UV aging causes the aggregation of asphalt molecules, and the aggregation of molecules narrows the molecular distribution boundary and moves in the direction of macromolecules, resulting in the reduction of the dispersion coefficient by 2–10%. Hydrogen atoms will undergo condensation and substitution reactions due to long-chain breaking, cyclization, or aromatization under UV action, and the breaking of C=C bonds in carbon atoms will increase the stable aromatic ring, strengthen the stiffness of the molecular backbone, and make it difficult for the backbone to spin. Through correlation analysis, it was found that the molecular composition index could characterize the aging behavior index of asphalt, and that the aromatic structure was the most critical molecular change. Further, it was found that the sulfoxide group and carbonyl group could be used as evaluation criteria for the UV aging of asphalt because the correlation between them was above 0.7. This study provides an essential index reference for evaluating the performance change of asphalt under ultraviolet aging to save testing time. Moreover, the molecular structure characterization revealed the changes in internal molecular composition that were behind the observed aging properties, providing a theoretical basis for research on asphalt anti-aging technology. Full article

β-glucans from filamentous fungi are important for human health. There is limited research on polysaccharides from filamentous fungi, and no reports have been published regarding the optimization of culture media to produce β-glucans from Rhizopus oryzae using liquid waste from potato starch processing. In this regard, the fermentation conditions to produce β-glucans from Rhizopus oryzae M10A1 were optimized using the one variable at a time (OVAT) and response surface methodology (RSM). The β-glucans were chemically characterized by determining moisture, nitrogen, protein, fat, ash, and total carbohydrates. The color, molecular weight, β-glucan content, monosaccharide composition, and structural and conformational characteristics were assessed by colorimetry, gel permeation chromatography, high-performance liquid chromatography, and Fourier transform infrared spectroscopy, respectively. The microbial indicators, mesophilic aerobes, molds, yeasts, and Escherichia coli were quantified following ISO standard protocols. Optimization indicated that supplementation with 0.8% (w/v) glucose and ammonium sulfate enhanced heteroglycan production (3254.56 mg/100 g of biomass). The β-glucans exhibited high purity, a light brown color, a molecular weight of 450 kDa, and a composition predominantly consisting of glucose and galactose. These findings suggest that β-glucans from Rhizopus oryzae M10A1 could be used for food and health applications. Full article

The present study investigates the potential of novel mixed matrix membranes that are formed from the biopolymer carboxymethyl cellulose (CMC) and the metal–organic framework ZIF-8 to improve the pervaporation dehydration of isopropanol. The effect of ZIF-8 content variation and porous substrate selection (comprising cellulose acetate (CA) and polyacrylonitrile) on dense and supported membrane properties is systematically investigated using multiple analytical techniques. It is found that ZIF-8 incorporation alters the membrane structure (confirmed by FTIR and NMR), increases surface roughness (observed via SEM and AFM), enhances swelling degree (obtained by swelling measurements), improves surface hydrophobicity (determined by contact angle analysis), and elevates thermal stability (verified by TGA). Quantum chemical calculations are used to validate the interactions between the polymer matrix, modifier, and feed components. The transport properties of developed membranes are evaluated through the dehydration of isopropanol via pervaporation. The cross-linked supported CMC membrane with 10 wt% ZIF-8 prepared on the CA substrate has the optimal performance: permeation flux of 0.136–1.968 kg/(m²h) and ˃92 wt% water in the permeate via the dehydration of isopropanol (water content 12–100 wt%) at 22 °C. Full article

In the era of the digital economy, where digitization permeates all sectors of society, digital transformation in agriculture stands as a crucial solution for addressing the growing challenges in agricultural production. Amid the competition to enhance the resilience of sustainable food systems, China sets an exemplary model with its achievements in digital agricultural transformation, providing a blueprint for developing countries in Asia and the Pacific. Primarily based on statistical data and typical case studies, this paper presents analytical findings on how digital transformation of agriculture enhances the adoption of green agricultural practices and promotes inclusive development in China. In light of the intricate challenges faced by China’s food system, the adoption of digitization emerges to facilitate the transformation from conventional agriculture to smart and sustainable practices. The pathways by which digital transformation of agriculture have the potential to address the over-application of chemical fertilizer and irrigation water, mitigation of carbon emissions, and the challenge of climate change and contribute to environmental sustainability of agriculture have been discussed. The implementation of digital transformation in sustainable agriculture—which enhances green practices and social inclusiveness by promoting digital literacy, reducing workload, creating job opportunities for low-skilled labor, and developing rural inclusive finance—has been completely explored. The challenges in digital transformation of agriculture are explained in this paper, which also provides evidence-based policy recommendations for its sustainable development applicable to developing countries. Full article

Polymer nanocomposites (PNCs) are a versatile class of materials known for their enhanced mechanical, thermal, electrical, and barrier properties, with the latter referring to resistance against the permeation of gases and liquids. Achieving optimal nanoparticle dispersion within the polymer matrix is essential to fully realizing these advantages. This study investigates strategies for improving nanoparticle dispersion and examines the impact of controlled dispersion on the resulting nanocomposite properties. Various methods, including in situ polymerization, twin screw extrusion, sol–gel processes, nanoparticle surface modification, solution casting, and advanced compounding techniques such as additive manufacturing and self-healing composites were explored to enhance dispersion and improve the compatibility between nanoparticles and polymers. The synergy between improved dispersion and enhanced functionalities—such as increased mechanical strength, thermal stability, conductivity, and chemical resistance—makes these nanocomposites highly valuable for industrial applications in sectors such as the automotive, aerospace, electronics, pharmaceuticals, and packaging industries. The key recommendations based on our findings highlight how customized nanocomposites can address specific industrial challenges, fostering innovation in materials science and engineering. Full article

The stability of cement slurries under high-temperature conditions poses a significant engineering challenge in cementing operations. This study explored the development of a novel tetrameric thermosensitive thickening polymer (TTSTC) as a solution to this problem. Aqueous free radical polymerization was employed to synthesize the polymer. The base monomers 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and acrylamide (AM) were employed, in conjunction with the long-chain thermosensitive monomers octadecyldimethylallylammonium chloride (C18DMAAC) and N-vinylpyrrolidone (NVP). The optimal synthesis conditions were determined by orthogonal experiments as follows: monomer molar ratio (AM:AMPS:C18DMAAC:NVP) = 15:10:5:5, initiator concentration of 16 wt%, cross-linker concentration of 0.45 wt%, pH 6, and polymerization temperature of 60 °C. The chemical structure of TTSTC was characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR), gel permeation chromatography, scanning electron microscopy, Zeta potential, and particle size measurement. The results verified the successful synthesis of the target polymer. Its thermal stability, thermosensitive thickening behavior, and salinity resistance were systematically investigated. Furthermore, the impact of TTSTC on the settling stability, rheological characteristics, and compressive strength of cement paste was assessed. The experimental findings demonstrated that TTSTC displayed noteworthy thermosensitive thickening properties at temperatures up to 279 °C, pH values ranging from 11 to 13, and NaCl/CaCl₂ concentrations between 0.05 and 0.5 g/L. The optimal performance of TTSTC was observed at mass fractions ranging from 0.6 to 0.8 wt%. When incorporated into the slurry at 0.6–1.0 wt%, TTSTC significantly improved the slurry settling stability, thickening properties, and 28d compressive strength at elevated temperatures compared with the control. When comparing the temperature-sensitive thickening performance of the newly developed treatment agent with that of the commercially available xanthan gum thickener, the results showed that for the cement slurry system containing the new treatment agent at a mass fraction of 0.6%, the reduction in consistency was 30.9% less than that of the cement slurry system with xanthan gum at a mass fraction of 0.6%. These findings indicate that TTSTC has the potential to function as a highly effective additive in cementing operations conducted in extreme environments, thereby enhancing the stability and dependability of such operations. Full article

Furan/maleimide dynamic covalent chemistry has been extensively used to fabricate re-workable and self-healing thermosets. Understanding the relationship between crosslinker structure, network dynamics, and material final properties, however, remains a challenge. This study introduces self-healing and shape-memory thermosets derived from furan-functionalized polyketones (PKFU) crosslinked with aromatic bis-maleimides, i.e., 1,1′-(methylenedi-4,1-phenylene)bis-maleimide (BISM1) and bis(3-ethyl-5-methyl-4-maleimidophenyl)methane (BISM2), via a thermally reversible Diels-Alder reaction. Polyketones were chemically modified with furfurylamine through the Paal-Knorr reaction, achieving varying furan grafting ratios. The resulting networks, characterized by ATR-FTIR, ¹H-NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and rheology, demonstrated tunable thermomechanical properties. BISM2-based thermosets exhibited enhanced thermal stability and reversibility over a broad temperature range (20–120 °C), with a shape recovery ratio of up to 89% and complete self-healing at 120 °C within 5 min. These findings highlight the potential of polyketone-based thermosets for applications requiring adaptive thermomechanical properties, efficient self-repair, and sustainability. Full article