Search Results (71)

In this work, ZnO nanoparticles were synthesized via a plant-mediated green route using Prosopis tamaulipana extract as a reducing and stabilizing agent and subsequently modified with silver to obtain Ag-modified ZnO powders. Structural and morphological characterization techniques confirmed the formation of nanocrystalline ZnO with a hexagonal wurtzite structure, submicrometric agglomerates composed of nanosized primary particles and a high degree of phase purity, indicating the effectiveness of the synthesis approach. The photocatalytic performance of the Ag-modified ZnO materials was evaluated under natural solar irradiation using methylene blue as a model organic contaminant in aqueous solution. Visual observations, together with absorbance, temperature and electrical conductivity measurements, demonstrated an effective and progressive degradation of the dye over a 5 h irradiation period. The observed increase in electrical conductivity under illumination was associated with enhanced charge carrier generation and improved separation efficiency, as well as the formation of reactive oxygen species, promoted by the presence of Ag as an electron sink. These results confirm that green-synthesized Ag-modified ZnO nanoparticles exhibit enhanced photocatalytic activity and are promising multifunctional materials for sustainable water sanitation applications. Full article

Background/Objectives: Cardiovascular diseases remain a leading cause of global mortality. The C-X-C motif chemokine ligand 12 (CXCL12) gene has been implicated in atherosclerosis; however, its relationship with lipoprotein subfraction profiles remains unclear. The primary objective of this study was to investigate the association between the CXCL12 rs1801157 C>T single nucleotide polymorphism (SNP) and coronary artery disease (CAD) risk in a Turkish population. The secondary objective was to evaluate the relationship between this polymorphism and LDL and HDL lipoprotein subfraction profiles. Methods: This case–control study included 139 patients with angiographically confirmed CAD and 125 healthy controls. Genotyping was performed using TaqMan real-time polymerase chain reaction (PCR). Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subfractions were analyzed using the Lipoprint^® polyacrylamide gel electrophoresis system. Multivariable logistic and linear regression analyses were performed, adjusting for age, sex, body mass index (BMI), and major cardiovascular risk factors. Results: No significant differences in rs1801157 genotype or allele distributions were observed between groups (overall χ² = 0.459, p = 0.796). Logistic regression confirmed that the polymorphism was not an independent predictor of CAD risk (CT: OR = 1.396, p = 0.409; TT: OR = 1.458, p = 0.694). HDL-C was an independent protective factor (OR = 0.952, 95% CI: 0.910–0.996; p = 0.029). Notably, TT homozygous carriers exhibited significantly higher large HDL (p = 0.018) and intermediate HDL (p < 0.001) subfraction levels and markedly lower small LDL concentrations (p < 0.001). Multivariable linear regression confirmed these associations were independent of age, sex, and BMI. Conclusions: The CXCL12 rs1801157 variant does not directly influence CAD susceptibility but modulates lipoprotein quality by promoting larger HDL subfractions and reducing atherogenic small LDL particles, suggesting an indirect cardioprotective role through lipid metabolism. Full article

Oral infections caused by antibiotic-resistant bacteria represent an emerging biomedical hazard and growing challenge for modern dentistry. To address this issue, Ag– and Cu–ZnO nanocomposites (NCs) were synthesized using ZnO carrier to combat the oral pathogens Streptococcus mutans and Streptococcus sobrinus. A comprehensive analysis of chemically synthesized metal oxide nanocomposites (MONCs) was performed, combining physicochemical characterization (TEM, XRD, ζ-potential, DLS, pH, and PFO/PSO kinetic models) with biological toxicity assessment (MIC, ATR–FTIR, SEM, and FAMEs) to better understand their antimicrobial mechanisms. The results confirmed that the synthesized nanoproducts fulfill the criteria for nanomaterials (NMs) (particle size < 100 nm). Among them, Ag–ZnO exhibited the highest antibacterial activity against both strains (MIC = 50 mg L⁻¹). Kinetic modeling revealed faster and more efficient Ag ion release from Ag–ZnO NCs compared to Cu from Cu–ZnO NCs. Molecular analyses indicated strong MONC–bacterial interactions at the cell surface, leading to changes in protein secondary structures, alterations in lipid composition, and disruption of Gram-positive bacterial membranes. Additionally, Ag–ZnO inhibited chain and cluster formation in both bacterial species, while Cu–ZnO affected only S. sobrinus. Overall, Ag– and Cu–ZnO NCs show strong potential as antimicrobial agents against oral pathogens. Full article

Efficient recovery of critical metals from complex polymetallic ores relies on clarifying their mineralogical occurrence. A Cd-Ag-rich Pb-Zn ore from southwestern China was investigated via a multi-scale process mineralogy approach integrating reflected-light microscopy, TIMA and LA-ICP-MS. Systematic analysis was conducted on ore texture, mineral liberation characteristics, and the occurrence and distribution of Ag and Cd. The ore is a medium–low grade Pb-Zn deposit (Pb 0.81%, Zn 4.33%) with economically recoverable associated Cd (0.066%) and Ag (5.04 ppm), dominated by sphalerite (7.74%), galena (1.39%), pyrite (3.92%), quartz (47.80%) and calcite (18.66%). TIMA analysis revealed poor liberation of sphalerite and galena, with fully liberated particles accounting for <30%. LA-ICP-MS results showed that Cd is highly enriched in sphalerite (average 5982 ppm, 98%) mainly in isomorphous form, while Ag is dispersed in pyrite (average 178 ppm, 56%), galena (average 227 ppm, 25%) and sphalerite (average 31 ppm, 19%), also primarily as isomorphs; partial Cd in pyrite occurs as micro-inclusions. The multi-scale mineralogical data provide a scientific basis for resource utilization, indicating the necessity of fine grinding and differentiated recovery strategies: “zinc depression followed by lead flotation” for Pb-Zn recovery, the establishment of a comprehensive Ag recovery system with Pb-Zn-Fe as carriers for Ag recovery, and “Zn-carried Cd” flotation for Cd recovery. This study verifies the effectiveness of combined TIMA and LA-ICP-MS in elucidating critical metal occurrence, and provides a mineralogy-based process design for the sustainable processing of such complex ores. Full article

The occurrence of haze pollution significantly deteriorates air quality and threatens human health, yet persistent knowledge gaps in real-time source apportionment of fine particulate matter (PM_2.5) hinder sustained improvements in atmospheric pollution conditions. Thus, this study employed single-particle aerosol mass spectrometry (SPAMS) to investigate PM_2.5 sources and dynamics during winter haze episodes in Yinchuan, Northwest China. Results showed that the average PM_2.5 concentration was 57 μg·m⁻³, peaking at 218 μg·m⁻³. PM_2.5 was dominated by organic carbon (OC, 17.3%), mixed carbonaceous particles (ECOC, 17.0%), and elemental carbon (EC, 14.3%). The primary sources were coal combustion (26.4%), fugitive dust (25.8%), and vehicle emissions (19.1%). Residential coal burning dominated coal emissions (80.9%), highlighting inefficient decentralized heating. Source contributions showed distinct diurnal patterns: coal combustion peaked nocturnally (29.3% at 09:00) due to heating and inversions, fugitive dust rose at night (28.6% at 19:00) from construction and low winds, and vehicle emissions aligned with traffic (17.5% at 07:00). Haze episodes were driven by synergistic increases in local coal (+4.0%), dust (+2.7%), and vehicle (+2.1%) emissions, compounded by regional transport (10.1–36.7%) of aged particles from northwestern zones. Fugitive dust correlated with sulfur dioxide (SO₂) and ozone (O₃) (p < 0.01), suggesting roles as carriers and reactive interfaces. Findings confirm local emission dominance with spatiotemporal heterogeneity and regional transport influence. SPAMS effectively resolved short-term pollution dynamics, providing critical insights for targeted air quality management in arid regions. Full article

The synthesis of graphitic carbon nitride (g-C₃N₄) coupled with tin sulfide (SnS) has been identified as an effective method for improving the photocatalytic and electrochemical performance of SnS, a promising material for environmental and energy-related applications. In this study, we focused on how g-C₃N₄ influences the structural, optical, electrochemical, and functional properties of SnS. XRD and FTIR confirmed the formation of SnS/g-C₃N₄ heterostructure, while surface morphology analysis by SEM showed proper dispersion of SnS particles over g-C₃N₄ with a good interface contact. The SnS/g-C₃N₄ composite itself demonstrated improved photocatalytic performance, with the degradation rate of methylene blue reaching approximately 94% under visible light irradiation compared to the moderate activity of SnS. This enhancement can be credited to the successful charge carrier separation enabled by the type II heterojunction created between SnS and g-C₃N₄. Moreover, the composite presented improved electrochemical activity with a specific capacitance of 1340 F·g⁻¹ at a scan rate of 10 A·g⁻¹ and good cycling stability, where the capacitance was 92% after 5000 cycles. As such, these SnS/g-C₃N₄ composites suggest the specific application of this class of material in photocatalytic degradation as well as energy storage, putting forward new effective resolutions to environmental and energy issues. Full article

In this work, a novel dual Z-scheme CdS/Ag₂MoO₄/β-Bi₂O₃ (CAB) composite heterojunction was synthesized, with the ultrafine CdS nanoparticles decorating two different-sized particles. In the beginning, the synergistic effect between BO and AMO makes the 10% Ag₂MoO₄/β-Bi₂O₃ (10AB) photocatalyst exhibit an optimal degradation efficiency of 87.1% for methylene blue (MB) of 10 mg·L⁻¹ within 60 min; furthermore, its photocatalytic activity was enhanced by incorporating CdS nanoparticles on the surface of the AB heterojunction. The results showed that the 25% CdS/10% AMO/BO (25C10AB) composite achieved a maximum MB degradation efficiency of 99%. Optical and photoluminescence measurements showed that the dual Z-scheme CAB heterojunction has high crystallinity and efficient charge carrier migration and separation, which makes the samples more efficient for removing pollutants. Theoretical studies (DFT/FEM calculations) were performed to better understand the migration direction of e⁻ and h⁺ in the photocatalytic degradation mechanism. This work provides a feasible approach to obtaining an efficient heterojunction composite photodegradation catalyst. Full article

Trans-resveratrol (RES) is a natural polyphenol known for its antioxidant, anti-inflammatory, and anti-aging properties, making it highly valuable in cosmetic applications. Solid lipid nanoparticles (SLNs) offer a promising solution to enhance RES’s stability and cutaneous availability. This study aimed to develop and characterize SLNs encapsulating RES for enhanced skin delivery. Multiple methodologies were evaluated to determine the impact of preparation methods on formulation stability. SLNs were formulated using stearic acid, soy phosphatidylcholine, polysorbate 80, cetyltrimethylammonium bromide, and poloxamer 407, with variations in heating temperatures and homogenization techniques. Stability assessments were conducted over 90 days, examining organoleptic properties of the hydrodynamic diameter, polydispersity index, and zeta potential. Encapsulation efficiency and skin permeation studies were performed to investigate the efficacy of SLNs in delivering RES. Results demonstrated that formulations prepared with Ultra Turrax at 24,000 rpm and heating at higher temperatures exhibited enhanced stability and smaller particle sizes. The selected formulations, F1 (prepared at 80 °C) and F2 (prepared at 70 °C) presented encapsulation efficiencies of 70% and 72%, respectively. Skin permeation studies confirmed the ability of SLNs to facilitate RES delivery through the skin. The study concludes that SLNs are suitable carriers for RES skin delivery, offering improved stability and sustained release, thus representing a promising approach for topical applications to leverage RES’s cutaneous therapeutic benefits. Full article

This study investigated the modification of nanosilver (Ag) by Co-Pc (phthal–cyanine) and the synergistic effect of Ag-Co/CNT (carbon nanotube) for the long-term stability of AEMFCs (anion exchange membrane fuel cells). This study also aimed to use non-precious metal catalysts on both the cathode and anode to reduce the catalyst costs. Through a simple and efficient chemical synthesis method, a composite catalyst consisting of Co-Pc-modified Ag/CNT was successfully prepared and characterized for its structure and composition. Co-Pc and Ag were chosen for their high durability and catalytic activity in fuel cells, combined with a multi-wall carbon nanotube (MWCNT) as a carrier for the cathode catalyst, and the anode catalyst used Pd-CeO₂/C. The performance of the cell module was tested based on a commercial anion exchange membrane (X37-50RT). The experiment focused on different synthesis times and ratios of catalyst and ionomer, observing the enhancement in Co on the active sites of Ag/CNT. Finally, the cell performance was tested for the optimal loading amount. It was observed that when the loading of the nanosilver–cobalt/carbon nanotube (Ag-Co/CNT) is 1 mg/cm², the highest power density is 434.1 mW/cm². Through 100 cycles of testing, only an 18% decrease was observed, while the decrease in open circuit voltage was approximately 4.6%. Compared to nanosilver (Ag/CNT), the Co-Pc-modified nano-Ag with the degradation rate has significantly slowed down, and its catalytic activity has also improved significantly. The enhanced stability of this synergistic effect is mainly attributed to the introduction of cobalt metal, which prevents excessive fusion of nano-Ag particles and surface oxidation, effectively maintaining durability in catalytic activity. Full article

Tuberculosis (TB) is one of the most common respiratory infections worldwide, and it is caused by Mycobacterium tuberculosis (Mtb). Mtb employs immune evasion mechanisms that allow the disease to become chronic. Despite extensive research, the host–pathogen interaction remains incompletely understood. Extracellular vesicles (EVs) are small membrane particles that play a regulatory role in infectious diseases. Host-derived EVs have been identified as carriers of proteins, messenger RNA, and lipids from both the host cells and the pathogens. In this study, we assessed the cargo of EVs in human macrophages infected with the virulent strain H37Rv of Mtb at 1 and 24 h post-infection (hpi). The results showed that 1 hpi, infected macrophages secreted EVs containing Mtb proteins (15 to 37 kDa) and Ag85 kDa, as well as RNA transcripts (ESAT-6, 5KST, Ag85, IS6110, 30 kDa, 19 kDa, and MPT64). However, these decreased at 24 hpi. The infection of macrophages with Mtb was observed to result in the release of EVs containing Ag85 protein and RNA transcripts of Mtb; this process appeared to diminish after 24 hpi, suggesting the existence of an evasion mechanism. Both Ag85 and the RNA transcripts could be potential biomarkers for the diagnosis of TB patients. Full article

Exosomes are cell-derived, membrane-surrounded particles that deliver bioactive molecules to various cells. Due to their small size, low immunogenicity, extended blood circulation, and involvement in cellular communication, they hold potential as effective drug carriers. Exosomes are present in various biological fluids, including mare’s milk, a traditional drink in Central Asia. This study aims to compare exosome isolation methodologies and determine the stability of mare’s milk-derived exosomes as potential therapeutic carriers. Three extraction methods—immunoprecipitation, size exclusion chromatography, and total exosome isolation—were compared in terms of exosome characteristics, purity, and content. The isolated exosomes were then loaded with quercetin, and their ability to increase its bioavailability was tested in vitro and in vivo. Total exosome isolation was identified as the most efficient method for producing high-quality exosomes. These exosomes were loaded with quercetin and compared to free quercetin and exosomes alone. Exosomes loaded with 80 µM quercetin significantly restored β-galactosidase activity and cellular viability in doxorubicin-treated cells, exhibiting similar potency to 160 µM free quercetin. In aged model animals, treatment with quercetin-loaded exosomes resulted in significantly less acute and subacute damage to the myocardium, kidneys, and liver compared to untreated control animals. This study provides a proof-of-concept that mare’s milk-derived exosomes can be effectively absorbed by cells and animal tissues, supporting their potential use as drug carriers. Full article

Background: Approximately 10–20% of subjects vaccinated with HBsAg-based hepatitis B virus (HBV) vaccines are non-responders. BM32 is a recombinant grass pollen allergy vaccine containing the HBV-derived preS surface antigen as an immunological carrier protein. PreS includes the binding site of HBV to its receptor on hepatocytes. We investigated whether immunological non-responsiveness to HBV after repeated HBsAg-based vaccinations could be overcome by immunization with VVX001 (i.e., alum-adsorbed BM325, a component of BM32). Methods: A subject failing to develop protective HBV-specific immunity after HBsAg-based vaccination received five monthly injections of 20 µg VVX001. PreS-specific antibody responses were measured by enzyme-linked immunosorbent assay (ELISA) and micro-array technology. Serum reactivity to subviral particles of different HBV genotypes was determined by sandwich ELISA. PreS-specific T cell responses were monitored by carboxyfluorescein diacetate succinimidyl ester (CFSE) staining and subsequent flow cytometry. HBV neutralization was assessed using cultured HBV-infected HepG2 cells. Results: Vaccination with VVX001 induced a strong and sustained preS-specific antibody response composed mainly of the IgG₁ subclass. PreS-specific IgG antibodies were primarily directed to the N-terminal part of preS containing the sodium taurocholate co-transporting polypeptide (NTCP) attachment site. IgG reactivity to subviral particles as well as to the N-terminal preS-derived peptides was comparable for HBV genotypes A–H. A pronounced reactivity of CD3⁺CD4⁺ lymphocytes specific for preS after the complete injection course remaining up to one year after the last injection was found. Maximal HBV neutralization (98.4%) in vitro was achieved 1 month after the last injection, which correlated with the maximal IgG reactivity to the N-terminal part of preS. Conclusions: Our data suggest that VVX001 may be used as a preventive vaccination against HBV even in non-responders to HBsAg-based HBV vaccines. Full article

Regarding photocatalytic oxidative desulphurization (PODS), titanium oxide (TiO₂) is a promising contender as a catalyst due to its photocatalytic prowess and long-term performance in desulphurization applications. This work demonstrates the effectiveness of double-doping TiO₂ in silver (Ag) and molybdenum (Mo) for use as a novel catalyst in the desulphurization of light-cut hydrocarbons. FESEM, EDS, and AFM were used to characterize the morphology, doping concentration, surface features, grain size, and grain surface area of the Ag/Mo powder. On the other hand, XRD, FTIR spectroscopy, UV-Vis, and PL were used for structure and functional group detection and light absorption analysis based on TiO₂’s illumination properties. The microscopic images revealed nanoparticles with irregular shapes, and a 3D-AFM image was used to determine the catalyst’s physiognomies: 0.612 nm roughness and a surface area of 811.79 m²/g. The average sizes of the grains and particles were calculated to be 32.15 and 344.4 nm, respectively. The XRD analysis revealed an anatase structure for the doped TiO₂, and the FTIR analysis exposed localized functional groups, while the absorption spectra of the catalyst, obtained via UV-Vis, revealed a broad spectrum, including visible and near-infrared regions up to 1053.34 nm. The PL analysis showed luminescence with a lower emission intensity, indicating that the charge carriers were not thoroughly combined. This study’s findings indicate a desulphurization efficiency of 97%. Additionally, the promise of a nano-homogeneous particle distribution bodes well for catalytic reactions. The catalyst retains its efficiency when it is dried and reused, demonstrating its sustainable use while maintaining the desulphurization efficacy. This study highlights the potential of the double doping approach in enhancing the catalytic properties of TiO₂, opening up new possibilities for improving the performance of photo-oxidative processes. Full article

The main goal of this study is the examination of polypropylene (PP) microplastics (MPs) as possible carriers of daily use pharmaceutical compounds. The selected compounds can be separated into three groups: (i) antibiotics (Trimethoprim, Metronidazole, Indomethacin, Isoniazid), (ii) anti-inflammatories (Ketoprofen, Diclofenac), and (iii) anti-hypertensive (Valsartan). Two types of PP MPs (virgin and UV-aged) were used in the experimental procedure, and the effect of time and the effect of the initial concentrations of the drugs were examined. The impact of various environmental factors such as pH, salinity, and natural organic matter were also explored. The last two factors were studied using real aqueous matrices such as wastewater and seawater. According to the obtained results, the highest uptake was observed in indomethacin (9.3 mg/g) and diclofenac (7.3 mg/g), owing to their physiochemical properties. Aged particles showed enhanced adsorption ability in accordance with the existing literature, as their adsorption capacity was between 0.5–1.5 times greater than that of the virgin ones. Regarding the desorption of compounds from the virgin and aged PP MPs at three different pH values, diclofenac and indomethacin exhibited the highest desorption capacity, while alkaline conditions favored the desorption ability of PP MPs for most of the target compounds. Full article

In the biomedical fields of bone regenerative therapy, the immobilization of proteins on the bioceramic particles to maintain their highly ordered structures is significantly important. In this review, we comprehensively discussed the importance of the specific surface layer, which can be called “non-apatitic layer”, affecting the immobilization of proteins on particles such as hydroxyapatite and amorphous silica. It was suggested that the water molecules and ions contained in the non-apatitic layer can determine and control the protein immobilization states. In amorphous silica particles, the direct interactions between proteins and silanol groups make it difficult to immobilize the proteins and maintain their highly ordered structures. Thus, the importance of the formation of a surface layer consisting of water molecules and ions (i.e., a non-apatitic layer) on the particle surfaces for immobilizing proteins and maintaining their highly ordered structures was suggested and described. In particular, chlorine-containing amorphous silica particles were also described, which can effectively form the surface layer of protein immobilization carriers. The design of the bio-interactive and bio-compatible surfaces for protein immobilization while maintaining the highly ordered structures will improve cell adhesion and tissue formation, thereby contributing to the construction of social infrastructures to support super-aged society. Full article