Search Results (4,372)

Exposure to ultraviolet (UV), particularly UVA radiation, is a primary driver of photoaging due to its deep dermal penetration, which triggers DNA damage, collagen degradation, and immune suppression. Chebulinic acid (CA), a polyphenolic compound from Terminalia chebula, exhibits potent antioxidant and anti-inflammatory properties against UVB-induced skin damage. However, its large molecular weight hinders transdermal delivery and the TAT_47–57 peptide (core of HIV-1 TAT) enables rapid transmembrane transport. Large particles with double-layer membrane structure and a diameter exceeding 1000 nm were obtained during the separation of plant-derived exosome-like nanoparticles (PELNs), which are not considered as PELNs (50–500 nm), after a mixture with TAT anchored to the surface of engineered artificial vesicles (EAVs) and extrusion causes membrane fusion, employed as novel nanocarriers to overcome the difficulty in skin penetration by leveraging their lipid bilayer structure and surface membrane-anchored TAT for efficient epidermal fusion and intercellular penetration. Furthermore, CA-loaded TAT-ePELNs demonstrate significant efficacy in mitigating UVA-induced photoaging. Collectively, this study expands the anti-UVR damage application spectrum of CA from UVB to UVA exposure and establishes a green, efficient, and biosafe strategy for transdermal drug delivery by utilization of non-PELNs generated during the preparation process of PELNs. Full article

To realize the commercial application of metal bipolar plates in proton exchange membrane fuel cells (PEMFCs), it is important to develop coatings that are both durable and have low interfacial contact resistance (ICR). In this study, atmospheric plasma spraying (APS) was utilized to prepare nickel–graphite (Ni–G) and copper–graphite (Cu–G) coatings on titanium bipolar plates. This study investigates the effect of different graphite contents on the phase composition, microstructure, corrosion resistance, and electrical conductivity of the coatings. The results show that higher graphite content leads to better performance. The potentiostatic corrosion current densities of the Ni–G and Cu–G coated bipolar plates are 1.05 × 10⁻⁴ A·cm⁻² and 0.91 × 10⁻⁴ A·cm⁻², respectively. Similarly, the ICR values of the coated bipolar plates are 25.2 mΩ·cm⁻² and 38.9 mΩ·cm⁻² before and after cathodic polarization for Ni–G, and 17.4 mΩ·cm⁻² and 21.2 mΩ·cm⁻² for Cu–G. These results suggest that metal–graphite coatings deposited by APS represent a viable strategy for titanium bipolar plates. Full article

Direct air capture (DAC) requires carbon capture interfaces that operate under highly dilute CO₂ conditions while minimizing thermal and chemical regeneration penalties. Carbonic anhydrase (CA) accelerates the reversible hydration of CO₂ to bicarbonate and is therefore a strong biocatalytic candidate for low-temperature CO₂ capture, but its implementation depends on candidate support materials that combine wet-state accessibility, chemical reactivity, mechanical processability and compatibility with membrane architectures. This study reports the preparation and screening of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS)-reactive biopolymer composite membranes for future carbonic anhydrase (CA) immobilization. Chitosan particles were precipitated with citrate or tripolyphosphate under high-shear homogenization and compared after lyophilization or convective drying. Chitosan-, shellac-, agarose- and cellulose-acetate-based films plasticized with glycerol and/or polyethylene glycol 400 (PEG-400) were then evaluated by optical microscopy, dry-state penetrometric puncture testing, qualitative EDC/NHS-reactivity mapping and Fourier-transform infrared spectroscopy (FTIR). Freshly precipitated chitosan particles showed dendrite-like high-surface morphologies, while lyophilization preserved porous flocculated aggregates and convective drying produced denser collapsed structures. Neat chitosan showed the highest dry-state puncture force (2.230 ± 0.173 N), whereas chitosan/shellac (0.377 ± 0.044 N) and agarose/chitosan/PEG-400 (0.386 ± 0.038 N) provided the strongest reactive-composite compromise between dry-state puncture resistance and EDC/NHS compatibility. The EDC/NHS reactivity map identified chitosan- and shellac-containing films as the chemically most relevant supports because they provide amine and/or carboxyl functionality, whereas agarose and cellulose acetate alone were not directly suitable for zero-length amidation. FTIR spectra confirmed polymer-specific functional signatures and EDC/NHS-associated changes in carbonyl, amide and C-O/C-O-C regions, especially in shellac- and chitosan-containing composites. The results identify chitosan/shellac as the lead candidate membrane and agarose/chitosan/PEG-400 as a hydration-rich comparator for subsequent carbonic anhydrase immobilization studies. This work should be interpreted as a first-stage materials-screening study of candidate membranes for enzyme immobilization. Full article

Most traditional photocatalysts exist in powder form and have the disadvantage of being difficult to recycle and causing secondary pollution to the environment after use. To overcome this drawback, this study combined natural biopolymer (silk fibroin (SF)) with a previously developed titanium-based photocatalytic material P/Ag/Ag₂O/Ag₃PO₄/TiO₂ (PAgT) and fabricated a novel SF/PAgT fiber membrane via electrospinning. During the synthesis process, through adjusting the mass concentration of the PAgT dopant (0–0.30 g/mL), a series of photocatalytic fiber membranes were prepared. The morphology and structure of the as-prepared membranes were characterized by various analytical methods, including scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), contact angle (CA) and thermogravimetric analysis (TGA). The SEM images confirmed that the SF/PAgT composite membrane possessed a protrusive and spindle-shaped structure. FT-IR results verified that the primary structure of SF in all the as-prepared SF/PAgT membranes belonged to the Silk II type. The binding of SF with the PAgT photocatalyst did not disrupt the chemical structure and original properties of SF. Moreover, the XRD and CA measurements indicated that the SF/PAgT-4 fiber membrane exhibited the stronger diffraction peaks of anatase TiO₂ crystal structure and enhanced hydrophilicity. The experimental results clarified that the PAgT photocatalyst was successfully loaded onto the SF fiber membrane by electrospinning. To evaluate the performance of the developed visible-light-driven photocatalytic fiber membranes, Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were selected as representative bacteria strains. The results demonstrated that SF/PAgT-4 exhibited the optimal antibacterial activity and can completely inactivate 10⁷ CFU/mL of E. coli and S. aureus within just 30 min and 60 min treatment, respectively, indicating the optimal doping mass concentration of PAgT during the synthesis process was 0.20 g/mL. Furthermore, the scavenger study proved that during the photocatalytic disinfection process by SF/PAgT-4, all three radicals, including ·OH, h⁺ and ·O₂⁻, participated in the current photocatalytic disinfection system. They were capable of attacking the bacterial cells, causing the cell membrane injury, thereby leading to the intracellular component leakage and inducing extensive bacterial inactivation. Hence, by virtue of its excellent recyclability (during five cycles) and thermal stability (below 250 °C), the developed SF/PAgT-4 fiber membrane holds immense potential for highly efficient and sustainable utilization in practical water treatment applications. Full article

Multifunctional membranes capable of simultaneously separating oil–water emulsions and removing organic dyes from complex aqueous systems have garnered considerable attention in recent years. However, the facile fabrication of high-performance membranes that integrate both separation and adsorption functions remains a significant challenge. Herein, we report the fabrication of a polyacrylonitrile/polyvinyl alcohol–chitosan (PAN/PVA-CS) bilayer membrane with asymmetric wettability via electrospinning. The micro/nanostructures and surface wettability of the as-prepared membranes were precisely tailored by modulating the chitosan (CS) concentration. The resultant PAN/PVA-CS membrane exhibited an overall separation efficiency exceeding 97.5% for mechanically emulsified samples. Notably, the PVA-CS layer demonstrated superhydrophilicity and excellent underwater oleophobicity, enabling the gravity-driven simultaneous separation of oil-in-water emulsions and adsorption of water-soluble Congo red dye without requiring external pressure. The maximum adsorption capacity for Congo red reached 61.3 mg g⁻¹, surpassing that of numerous reported membrane-based and adsorbent materials. Concurrently, the hydrophobic PAN layer in the bilayer structure enabled the separation of water-in-oil emulsions. Overall, this work provides a promising strategy for the rational design of asymmetrically wettable multifunctional membranes with great potential for practical application in the purification of complex industrial wastewater containing both emulsified oils and soluble organic dyes. Full article

Small-molecule hydrogels have gradually become a research hotspot compared with polymeric hydrogels, but their practical advantages have not been fully realized in the development of pharmaceutical formulations. This study aimed to explore whether the N-methyl-D-glucosamine (GLU) could be introduced to form a ibuprofen (IBU) hydrogel for overcoming its water solubility defect and optimizing its pharmaceutical properties. Such an IBU-GLU hydrogel was prepared by simply mixing IBU with GLU in small-volume deionized water. The formed IBU-GLU hydrogel was characterized by SEM, rheology, DSC, PXRD and FTIR analyses. In addition, the solubility, in vitro release and permeability were also investigated to evaluate the solubilization and permeability-promoting effects. The resulting IBU-GLU hydrogel exhibited a typical 3D structure with excellent viscoelasticity, which relied on the equilibrium of aggregation and dissolution, as well as a good miscibility between IBU and GLU, and self-assembly driven by intermolecular interactions in an aqueous environment. Compared to pure IBU, the IBU solubility of the IBU-GLU hydrogel was significantly improved by 38.4-fold. Furthermore, IBU-GLU hydrogel demonstrated superior release rates and supersaturation ability, which was attributed to its high-energy state and internal molecular complexation. Additionally, compared with the commercially available IBU hydrogel, the prepared IBU-GLU hydrogel significantly accelerated IBU membrane permeation. Thus, this study highlighted that the designed IBU-GLU hydrogel could serve as a feasible approach to enhance the release and permeability of IBU for its druggability optimization. Full article

Reduced-oxide titanium (Ti) protective coatings were fabricated on 316L stainless-steel substrates to improve the corrosion resistance of low-cost metallic components for proton exchange membrane water electrolysis (PEMWE). A low-temperature atmospheric plasma spraying process assisted by a self-designed extended protective nozzle was employed to suppress the oxidation of Ti particles during deposition. The nozzle provided auxiliary argon shielding and reduced the thermal exposure of in-flight particles, thereby limiting their interaction with ambient air. The deposited coatings exhibited a continuous lamellar structure with average thicknesses of approximately 78–98 μm. Phase and elemental analyses indicated that α-Ti(O) was the dominant phase, with limited oxide formation in the coating. ONH analysis further showed that the oxygen and nitrogen contents of the coatings were 0.95–1.69 wt.% and 0.049–0.087 wt.%, respectively. During the 6 h potentiostatic test, all Ti-coated samples showed lower and more stable current densities than bare stainless steel, with the 500 A 55 V coating maintaining the lowest final current density of approximately 0.4–0.5 mA/cm². These results demonstrate that low-temperature atmospheric plasma spraying is a feasible and cost-effective approach for preparing reduced-oxide Ti coatings for PEMWE components. Full article

Background/Objectives: Antimicrobial resistance (AMR), microbiota disruption, and chronic inflammation have intensified the search for alternative and complementary antimicrobial strategies. Probiotics and plant-derived bioactive compounds (phytochemicals) are increasingly being investigated as microbiota-supporting, immunomodulatory, and antimicrobial agents. This review synthesizes the current evidence on probiotic–phytochemical interactions, with particular emphasis on mechanisms relevant to antimicrobial synergy, gut barrier reinforcement, microbiota modulation, and translational development. Methods: A narrative literature review with a structured search strategy was conducted using major scientific databases, including PubMed, Scopus, EBSCO, Google Scholar, SpringerLink, Wiley Online Library, and Taylor & Francis, and open repositories. Publications from January 2016 to April 2026 were considered, with an emphasis on experimental, preclinical, clinical, and mechanistic studies addressing the combined use of probiotics, postbiotics, plant extracts, or defined phytochemicals. Results: Available evidence indicates that selected probiotic–phytochemical combinations may enhance antimicrobial activity through complementary mechanisms, including pathogen membrane destabilization, inhibition of adhesion and biofilm formation, quorum-sensing interference, stimulation of probiotic viability and metabolite production, and biotransformation of phytochemicals into more active derivatives. These interactions may also support epithelial barrier integrity and immune regulation. However, the evidence remains heterogeneous and is strongly influenced by probiotic strain identity, phytochemical composition, dose, formulation, and the experimental model. Most studies are still limited to in vitro or animal models, and clinical validation remains scarce. Conclusions: Probiotic–phytochemical combinations represent a promising but insufficiently standardized strategy for antimicrobial and microbiota-targeted interventions. Future progress requires chemically characterized plant preparations, strain-level probiotic selection, harmonized synergy assays, advanced delivery systems, and well-designed clinical trials. Full article

Folate is an essential vitamin associated with protein and DNA synthesis in the body. Compared with synthetic folic acid, 6S-5-methyltetrahydrofolate calcium salt crystal form C (MTHF CAC) is safer and has a higher bioavailability. In this study, a nanofiber membrane (MT-GE) was prepared from fish gelatin and MTHF CAC in the aqueous system via electrospinning. Differential scanning calorimetry showed higher transition temperatures for MT-GE than for GE. The weight loss curve of MT-GE detected by thermogravimetric analysis was higher than that of GE. The results corresponded to those of X-ray diffraction, which indicated the slightly higher crystalline strength of MT-GE than GE. Therefore, the inclusion of MTHF CAC improved the physical characteristics of GE nanofibers. High-performance liquid chromatography analysis revealed that the retention of MTHF CAC in MT-GE reached 85.57%, which suggested that electrospinning caused no effect on the properties of MTHF CAC. The MT-GE membrane supported cell proliferation, and the Cell Counting Kit-8 results indicated that the cell proliferation rate exceeded 100%, with the MT-GE solution demonstrating more than double the proliferation rate of the control group. Therefore, MT-GE has great potential for use as a medical biomaterial. Full article

Platelet-rich fibrin (PRF) has been widely used in regenerative dentistry because of its potential to support tissue regeneration. Recently, modifications in PRF preparation protocols and tube surface characteristics have attracted attention because of their possible influence on fibrin organization and biologic activity. The present in vitro study aimed to evaluate the effects of nano-hydroxyapatite platelet-rich fibrin (HA-PRF) on gingiva-derived mesenchymal stem cells (GMSCs) by comparing it with leukocyte platelet-rich fibrin (L-PRF) and titanium platelet-rich fibrin (T-PRF). Gingival tissue and venous blood samples were obtained from a systemically healthy male volunteer. PRF membranes were prepared using conventional glass tubes, nano-hydroxyapatite-coated tubes, and titanium tubes. GMSCs were isolated, characterized, and cultured with PRF membranes. Cell viability and metabolic activity were evaluated using MTT analysis. Apoptosis and necrosis rates were assessed by Annexin V/PI flow cytometry. VEGF and TGF-β1 release levels were determined by ELISA, whereas IL-1β, IL-6, and TNF-α gene expression levels were analyzed using qRT-PCR. The HA-PRF and L-PRF groups demonstrated higher cell viability values compared with the T-PRF group on day 7. Annexin V/PI analysis revealed no statistically significant differences between the groups in terms of apoptosis and necrosis. Growth factor release and cytokine gene expression profiles demonstrated time-dependent biologic responses in all PRF membranes. Within the limitations of this study, HA-PRF showed no evidence of cytotoxicity and demonstrated biologic responses comparable to those observed with conventional L-PRF. Both HA-PRF and L-PRF generally exhibited more favorable cellular responses than T-PRF under the present experimental conditions. Full article

Oat-based beverages are increasingly popular milk alternatives. However, the heat treatment required to ensure shelf stability is limited by rapid fouling formation on heated surfaces, reducing processing efficiency. Oat proteins, considered an important quality attribute of oat drinks, are suspected to play a key role in fouling initiation, but their specific contribution remains poorly understood. This study investigates the role of oat proteins in fouling formation during heat treatment on technical scale. Membrane filtration was applied and validated as sample preparation method for increasing the protein content. Fouling experiments were conducted using a previously validated fouling system with feed solutions containing different protein concentrations. Protein content was increased by filtration using 0.1, 0.8 and 1.4 µm ceramic membranes, yielding retentates with 10–21 g·100 g⁻¹ on a dry matter basis, and further enriched to >40 g·100 g⁻¹ through diafiltration. Fouling experiments (140 °C, 60 min) revealed a dependence of fouling formation on protein content in the feed solution. Fouling deposits were negligible at low protein concentrations (<2.5 g·100 g⁻¹), increased markedly between 8 and 14 g·100 g⁻¹, and reached a plateau at higher protein levels. Using oat supernatant or retentates, the protein content in the fouling correlated linearly with the protein content in the feed solution (R² = 0.98) but did not exceed ~25 g·100 g⁻¹, resulting in predominantly carbohydrate-based deposits. In contrast, diafiltered protein-enriched feed solutions produced larger, protein-dominated deposits. A conceptual model describing feed-dependent fouling mechanisms is proposed. Full article

Integral membrane proteins (IMPs), which constitute 50–60% of drug targets, play essential roles in numerous biological processes but remain underrepresented in conventional bottom-up and structural proteomics owing to their hydrophobicity and resistance to proteolysis. Although advances in IMP proteomics have improved global IMP detection, most efforts focus on proteome-scale protein identification rather than targeted structural analysis. Protein footprinting and cross-linking, two approaches in structural proteomics, require high sequence coverage and protein digestion to peptides of suitable length for structural elucidation, necessitating optimized digestion condition for individual IMPs. Here, we report a digestion protocol tailored for structural mass spectrometry and evaluate its performance by using a single amphipathic IMP model featuring distinct extramembrane and transmembrane domains. We evaluated the use of various protease–additive combinations and applied filter-aided sample preparation (FASP) to remove detergents and surfactants efficiently prior to MS analysis. The optimized conditions consistently yielded >90% sequence coverage. Guided by MS retention time calibration and hydrophobic factor simulations, we identified a “sweet spot” for transmembrane peptide detection. Notably, although cleavable surfactants can enhance proteome-wide coverage, our results show that they are not essential for single protein studies as they are in structural proteomics. Instead, detergent removal, protease selection, and generation of suitably sized peptides are critical for enabling reliable bottom-up structural analysis of IMPs. The protocol developed here provides a practical framework for optimizing digestion conditions in IMP characterization. Full article

Background/Objectives: Lipid nanoparticles (LNPs) have emerged as crucial vehicles for messenger RNA (mRNA) applications in antitumor therapy. Combining LNPs with stimulator of interferon genes (STING) activation holds promise for treating “cold” tumors such as pancreatic cancer. However, two major challenges remain: inefficient mRNA escape from endosomes and STING pathway suppression in immunosuppressive tumor microenvironments. Methods: To improve endosomal escape, we developed a novel pH-responsive PEGylated lipid (Ben-mPEG₂₀₀₀) for mRNA-LNP preparation while using commercial Man-mPEG₂₀₀₀ for dendritic cell (DC)-targeted delivery of LNPs; to alleviate suppression of the STING pathway in the tumor microenvironment and activate immune responses, STING-R283S mRNA was encapsulated into LNPs, ultimately resulting in DC-targeted/pH-responsive LNPs loaded with STING-R283S mRNA for pancreatic cancer immunotherapy research. Results: After pH-responsive cleavage, Ben-mPEG₂₀₀₀ not only enhanced the positive charge of LNPs through the exposed protonated amino groups but also eliminated the PEG-induced steric hindrance effect. The combination of these two effects promoted membrane fusion between LNPs and the endosome, thereby enhancing mRNA translation. As a payload, STING-R283S could further amplify STING signaling in DCs without cytotoxicity to counteract immunosuppression in pancreatic cancer. Conclusions: This engineered LNP platform enhanced mRNA expression and STING activation in DCs, improving immunotherapy outcomes in pancreatic cancer. Full article

Electrospun sulfonated polyketone (PK) nanofiber membranes were prepared to investigate the sulfonation-time-dependent structure–property relationships of hydrocarbon-based polymer electrolyte membranes for PEMFC (Polymer Electrolyte Membrane Fuel Cell) applications. NaCl addition to the electrospinning solution increased solution conductivity and enabled the formation of uniform PK nanofibers with an average diameter of approximately 270 nm. Subsequent sulfonation introduced sulfonic-acid-related groups into the PK nanofiber framework, and the resulting membrane properties were strongly governed by sulfonation time. Among the tested membranes, PK-NC16 exhibited the highest proton conductivity of 0.107 ± 0.031 S cm⁻¹ and an ion exchange capacity of 2.82 m_eq g⁻¹, exceeding or comparable to those of Nafion 115 under the tested conditions. FTIR-based analysis indicated that the relative sulfonation index increased up to 16 h, whereas extended sulfonation for 24 h generated additional sulfone/sulfonate-related bands, suggesting possible side reactions or structural changes under prolonged acid treatment. The high water uptake of PK-NC16 enhanced proton transport but also revealed a hydration-sensitive polymer network, as reflected by a voltage degradation rate of approximately −590 μV h⁻¹ during a 100 h short-term stability constant-current test. These results demonstrate that sulfonation time is a key parameter controlling the balance among ionic functionality, hydration, mechanical response, proton conductivity, and PEMFC-relevant single-cell performance in electrospun PK nanofiber membranes. Full article

Asymmetric SiC membranes with surface pore sizes ranging from 0.12 to 0.31 μm at a constant open porosity of approximately 42% were fabricated by dip-coating SiC support followed by sintering from 1700 to 2000 °C. The effect of membrane structural constants (hydraulic resistance (k₁), pore size exponent (k₂), and shape factor (k₃)) on PWP were evaluated by comparing the symmetric and asymmetric structures. In addition, the experimentally determined values of PWP were quantitatively analyzed by comparing with theoretically predicted values obtained using the Kozeny–Carman (K–C) and Hagen–Poiseuille (H–P) models. Despite having a smaller pore size, the asymmetric membranes exhibited high PWP (1257-3883 LMH) due to decreased flow resistance (low k₁), enhanced pore size effect (high k₂), and improved flow network (high k₃) as compared to symmetric membranes. The hydrophilicity of the prepared membranes improved remarkably, with increasing average surface roughness (102.3 nm to 161.0 nm) due to an increase in pore size, which also caused a decrease in water contact angle (WCA) from approximately 27.44° to 21.67° with increasing sintering temperature (1700–2000 °C). Furthermore, the prepared membrane separation performance was found to be affected by its pore size, and the 1900 °C sintered SiC membrane showed optimal gradient profile and pore structure, demonstrating its practical reusability and scalability for O/W wastewater treatment. Full article