Search Results (3,057)

Due to the indiscriminate use of antimicrobial drugs in the treatment of infectious diseases, human pathogenic bacteria have developed resistance to many commercially available antibiotics. Medicinal plants such as Convolvulus arvensis represent a renewable resource for the development of alternative therapeutic agents. This study aimed to evaluate the antibacterial activity of silver nanoparticles (AgNPs) biosynthesized from C. arvensis against two clinical antibiotic-resistant bacterial isolates. The pathogenic isolates were identified as Staphylococcus aureus MRSA and Escherichia coli ESBL using 16S rRNA gene sequencing. Silver nanoparticles were synthesized via a green synthesis approach, and their physicochemical properties were characterized using UV–Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, zeta potential, and dynamic light scattering (DLS). The synthesized C. arvensis–AgNPs exhibited a surface plasmon resonance peak at 475 nm and predominantly spherical morphology with particle sizes ranging from 102.34 to 210.82 nm. FTIR analysis indicated the presence of O–H, C–O, C–N, C–H, and amide functional groups. The nanoparticles showed a zeta potential of −18.9 mV and an average hydrodynamic diameter of 63 nm. The antibacterial activity of the biosynthesized AgNPs was evaluated against methicillin-resistant S. aureus (MRSA and ATCC 29213) and E. coli (ESBL and ATCC 25922) using agar diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays. Inhibition zones ranged from 10 to 13 mm, with MIC and MBC values of 12.5–25 µg/mL and 25–50 µg/mL, respectively. In addition, the nanoparticles exhibited antioxidant activity (DPPH assay, IC₅₀ = 0.71 mg/mL) and anti-inflammatory effects as determined by protein denaturation inhibition. No cytotoxic effects were observed in the MCF-7 cell line at the MIC level. These findings suggest that C. arvensis–AgNPs have potential as natural antimicrobial, antioxidant, and anti-inflammatory agents. Full article

Cemented granular materials (CGMs) represent a transitional class of geomaterials where mechanical behavior is governed by the interplay between a discrete granular skeleton and a continuous cementitious matrix. While previous studies have focused on idealized spherical particles, this study aims to quantify the influence of the cement filling ratio (ranging from 10% to 100%) on the mechanical constitutive behavior of CGMs fabricated with large, irregular granitic aggregates (14–20 mm). Unconfined compressive tests and splitting tensile tests were conducted to evaluate the evolution of strength, stiffness, and failure modes. The results reveal a distinct mechanical transition governed by the cement filling ratio (${\rho }_m$). The elastic modulus and splitting tensile strength exhibited a linear increase with ${\rho }_m$ (R2 > 0.95), indicating a direct dependence on the volume fraction of the binding phase. In contrast, the unconfined compressive strength (UCS) and peak strain displayed a bilinear growth pattern with a critical inflection point at ${\rho }_m$ = 80%. For the specific irregular granitic aggregate skeleton investigated, this threshold marks the transition from contact-dominated stability to matrix-dominated continuum behavior. Below this threshold, strength gain is limited by the stability of discrete particle contacts; above 80%, the material behaves as a continuum, with UCS increasing rapidly to a maximum of 41.78 MPa at 100% filling. Furthermore, the dispersion of stress–strain responses significantly decreased as ${\rho }_m$ exceeded 50%, attributed to the homogenization of stress distribution within the specimen. These findings provide a quantitative basis for optimizing cement usage in ground reinforcement applications, identifying 80% as a critical design threshold. Full article

A sustainable hybrid material, CuO/Cu₂O, was synthesized using an aqueous extract of Curcuma longa L. as a reducing and stabilizing agent. The material was characterized by UV-Vis spectroscopy, FTIR, XRD, SEM, EDX, and TEM. XRD analysis revealed peaks corresponding to CuO and Cu₂O phases with crystallite sizes of 15.88 nm and 16.71 nm, respectively. TEM images showed nearly spherical particles with some agglomeration and an average particle diameter of 8.17 nm. The hybrid material exhibited catalytic activity toward the synthesis of 1,2,3-triazoles in water, under low catalyst loading and mild reaction conditions. This work highlights the potential of Curcuma longa-mediated synthesis as a low-cost, eco-friendly alternative for producing efficient catalysts, contributing to the advancement of green chemistry and sustainable nanomaterial applications in organic synthesis. Full article

High-energy methods dominate the development of lipid nanoparticles but often require specialized equipment that increases production costs. Low-energy approaches, particularly those free of organic solvents, offer a promising alternative. This study aimed to obtain nanostructured lipid carriers (NLCs) using a solvent-free, low-energy process combining microemulsification and phase inversion. Cetearyl alcohol and PEG-40 hydrogenated castor oil were selected as the solid lipid and surfactant, respectively; the formulation and process were optimized through a Box–Behnken Design. Incorporation of the ionic surfactant extended colloidal stability, while the poloxamer in the aqueous phase enhanced steric stabilization. Resveratrol was efficiently encapsulated (E.E. = 98%), contributing to reduced particle size (291 nm), improved homogeneity (PDI = 0.25), and positive surface charge (+43 mV). Scale-up yielded stable particles carrying resveratrol with a mean size of 507 nm, PDI = 0.24, and ZP = +52 mV. The optimized formulation remained stable for 90 days at 8 °C. In vitro release demonstrated a sustained and controlled release profile, with significantly lower resveratrol release compared to the free compound. Thermal analysis confirmed drug incorporation within the lipid matrix, while transmission electron microscopy (TEM) revealed spherical particles (~200 nm) and SAXS indicated a nanostructure of ~50 nm. Overall, this study demonstrates that solvent-free, low-energy processing can produce stable and scalable NLC formulations, successfully encapsulating resveratrol with favorable physicochemical properties and controlled release behavior. These findings highlight a simple, cost-effective strategy for developing lipid-based nanocarriers with potential applications in drug delivery. Full article

Glass ionomer cements (GICs) are widely used in restorative and luting dentistry due to their fluoride release and chemical adhesion to dental tissues; however, their limited mechanical strength necessitates reinforcement strategies. The objective of this study was to investigate the effects of hemp-derived, green-synthesized titanium dioxide (TiO₂) nanoparticles on the surface and mechanical properties of two commercially available GICs with different clinical indications. TiO₂ nanoparticles were synthesized using Cannabis sativa leaf extract via a biogenic reduction method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), confirming anatase-phase crystallinity, spherical morphology, and nanoscale particle size (28–49 nm). The nanoparticles were incorporated into Ketac™ Molar Easymix (restorative) and Ketac™ Cem Radiopaque (luting) GICs at 1%, 3%, and 5% (w/w), with nanoparticle-free formulations serving as controls (n = 10). Surface roughness, Vickers microhardness, and flexural strength were evaluated. Surface roughness increased in a concentration-dependent manner in both materials, with the highest values observed at 5% TiO₂ incorporation. In Ketac™ Molar Easymix, 1% and 3% TiO₂ significantly enhanced flexural strength and microhardness, whereas 5% resulted in reduced performance, consistent with SEM-observed nanoparticle agglomeration. In contrast, Ketac™ Cem Radiopaque exhibited no significant changes in flexural strength, although maximum microhardness values were recorded at 1% TiO₂ concentration. These findings demonstrate that low concentrations of hemp-derived TiO₂ nanoparticles can effectively reinforce restorative GICs and highlight the potential of green nanotechnology as a sustainable approach for improving dental biomaterials. Full article

This is the first investigation that attempts to synthesize chitosan-loaded vanillin nanoformulation (vanillin-Nf) as a novel edible coating agent to prolong the storage life of Indian gooseberry (amla). Different concentrations of vanillin were encapsulated into chitosan via ionic gelation approach using sodium tripolyphosphate as a cross-linker. Vanillin-Nf 1:1 (w/v) exhibited maximum loading capacity (2.502 ± 0.008%) and encapsulation efficiency (54.483 ± 1.165%). The physico-chemical characterization of vanillin-Nf through SEM, DLS, FT-IR, and XRD techniques confirmed effective incorporation of vanillin into the chitosan biomatrix and formation of spherical nanocapsules, with a mean particle size of 232.83 nm, zeta potential +69.66 mV, and polydispersity index 0.296. The in vitro release profile of vanillin exhibited a biphasic and regulated release pattern. The application of vanillin-Nf as an edible coating solution on amla (Phyllanthus emblica L.) fruits was highly effective in reducing decay incidence up to 42.84% and extended their shelf-life to 15 days at 25 ± 2 °C. The vanillin-Nf coating significantly reduced weight loss in amla fruits (24.39 ± 1.02%) in comparison to control. In addition, vanillin-Nf coating also helped in preserving the key quality parameters, including pH, chlorophyll content, total soluble solids, total phenols, and antioxidant capacity of Indian gooseberries to a substantial extent at the end of storage. Collectively, our findings indicate that vanillin-Nf coating is an effective post-harvest approach for controlling decay, prolonging shelf-life, and maintaining the nutritional attributes of Indian gooseberries, highlighting its potential for commercial application in the food and agriculture industry. Full article

The present study reports the design and physicochemical characterization of a hybrid nanoparticle system for the potential intranasal delivery of galantamine (GAL), aimed at improving its bioavailability. Carbon dots (CDs) were used to load GAL, enhancing its dissolution and stability, and were subsequently incorporated into a poly(lactic-co-glycolic acid)–curcumin (PLGA–Cur) conjugate matrix. The successful formation of the PLGA-Cur conjugate was verified via ¹H-NMR and FTIR spectroscopy, while the loading of GAL and its physical state in the CDs was assessed via FTIR and pXRD, respectively. The resulting GAL-CD/PLGA–Cur nanoparticles were spherical, with particle sizes varying from 153.7 nm to 256.3 nm, a uniform morphology and a narrow size distribution. In vitro release studies demonstrated a multi-phase sustained release pattern extending up to 12 days. Spectroscopic and thermal analyses confirmed successful conjugation and molecular interactions between GAL and the carrier matrix. This proof-of-concept hybrid system demonstrates promising controlled, multi-phase sustained galantamine release in vitro, highlighting the role of curcumin conjugation in modulating polymer structure and release kinetics and providing a foundation for future biological evaluation. Full article

The development of upper-limb prostheses is often hindered by limited dexterity, a restricted workspace, and bulky designs, primarily due to performance limitations in proximal joints like the shoulder and elbow, which contribute to high user abandonment rates. To overcome these challenges, this paper presents a novel, bioinspired, and integrated prosthetic system as an advancement in bionic technology. The design incorporates a shoulder joint based on an asymmetric 3-RRR spherical parallel mechanism (SPM) with actuators embedded within the moving platform, and an elbow joint actuated by low-voltage Shape Memory Alloy (SMA) springs. The inverse kinematics of the shoulder mechanism was established, revealing the existence of up to eight configurations. We employed Multi-Objective Particle Swarm Optimization (MOPSO) to simultaneously maximize workspace coverage, enhance dexterity, and minimize joint torque. The optimized design achieves remarkable performance: (1) 85% coverage of the natural shoulder’s workspace; (2) a maximum von Mises stress of merely 3.4 MPa under a 40 N load, ensuring structural integrity; and (3) a sub-0.2 s response time for the SMA-driven elbow under low-voltage conditions (6 V) at a motion velocity of 6°/s. Both motion simulation and prototype testing validated smooth and anthropomorphic motion trajectories. This work provides a comprehensive framework for developing lightweight, high-performance prosthetic limbs, establishing a solid foundation for next-generation wearable robotics and bionic devices. Future research will focus on the integration of neural interfaces for intuitive control. Full article

Introduction: Magnetic nanoparticles are widely investigated as multifunctional platforms for drug delivery and theranostic applications, yet their biomedical implementation is hindered by aggregation, limited colloidal stability, and insufficient biocompatibility. Hybrid biopolymer coatings can mitigate these issues while supporting drug incorporation. Aim: This study aimed to develop casein–pullulan-coated Fe₃O₄ nanocomposites loaded with xanthohumol, enhancing stability and enabling controlled release for potential theranostic use. Methods: Fe₃O₄ nanoparticles were synthesized through co-precipitation and incorporated into a casein–pullulan matrix formed via polymer complexation and glutaraldehyde crosslinking. A 3² full factorial design evaluated the influence of casein:pullulan ratio and crosslinker concentration on physicochemical performance. Nanocomposites were characterized for size, zeta potential, morphology, composition, and stability, while drug loading, encapsulation efficiency, and release profiles were determined spectrophotometrically. Molecular docking was performed to examine casein–pullulan interactions. Results: Uncoated Fe₃O₄ nanoparticles aggregated extensively, displaying mean sizes of ~292 nm, zeta potential of +80.95 mV and high polydispersity (PDI above 0.2). Incorporation into the biopolymer matrix improved colloidal stability, yielding particles of ~185 nm with zeta potentials near –35 mV. TEM and SEM confirmed spherical morphology and uniform magnetic core incorporation. The optimal formulation, consisting of a 1:1 casein:pullulan ratio with 1% glutaraldehyde, achieved 5.7% drug loading, 68% encapsulation efficiency, and sustained release of xanthohumol up to 84% over 120 h, fitting Fickian diffusion (Korsmeyer–Peppas R² = 0.9877, n = 0.43). Conclusions: Casein–pullulan hybrid coatings significantly enhance Fe₃O₄ nanoparticle stability and enable controlled release of xanthohumol, presenting a promising platform for future targeted drug delivery and theranostic applications. Full article

A multifunctional diagnosis and treatment carrier, ZIF-8@CDs, based on carbon quantum dots (CDs) and the zeolitic imidazolate framework-8 (ZIF-8) metal–organic framework which serves as a core structure for constructing the responsive delivery platform, is developed in this paper. The anticancer drug doxorubicin (DOX) and Survivin oligo (siRNA) are loaded to form a ZIF-8@CDs/DOX@siRNA dual loading platform. CDs of 5–10 nm are synthesized by the solvent method and combined with ZIF-8. Electron microscopy shows that the composites are nearly spherical particles of approximately 200 nm, and the surface potential decreases from +36 mV before loading CDs to +25.7 mV after loading. The composite system shows unique advantages: (1) It has Fenton-like catalytic activity, catalyzes H₂O₂ to generate hydroxyl radicals, and consumes glutathione in the tumor microenvironment. The level of reactive oxygen species (ROS) in the ZIF-8@CDs group is significantly higher than that in the control group. (2) To achieve visual diagnosis and treatment, its fluorescence intensity is superior to that of the traditional Fluorescein isothiocyanate (FITC)-labeled vector; (3) It has a high loading capacity, with the loading amount of small nucleic acids reaching 36.25 μg/mg, and the uptake rate of siRNA by liver cancer cells is relatively ideal. The ZIF-8@CDs/DOX@siRNA dual-loading system is further constructed. Flow cytometry shows that the apoptosis rate of HepG2 cells induced by the ZIF-8@CDs/DOX@siRNA dual-loading system is 49%, which is significantly higher than that of the single-loading system (ZIF-8@CDs/DOX: 34.3%, ZIF-8@CDs@siRNA: 24.2%) and the blank vector (ZIF-8@CDs: 12.6%). The platform provides a new strategy for the integration of tumor diagnosis and treatment through the multi-mechanism synergy of chemical kinetic therapy, gene silencing and chemotherapy. Full article

Ascaris lumbricoides is one of the most epidemiologically significant soil-transmitted helminths, and the environmental persistence of its eggs is largely attributed to their robust structural architecture. The search for ovicidal alternatives capable of overcoming this barrier has increasingly focused on metallic nanoparticles obtained through biological synthesis. Scanning electron microscopy (SEM) was employed to evaluate the ultrastructural effects of silver nanoparticles (AgNPs) biosynthesised by the nematophagous fungus Duddingtonia flagrans on A. lumbricoides eggs. Ultraviolet-visible spectroscopy and transmission electron microscopy confirmed the synthesis of AgNPs, revealing predominantly spherical, well-dispersed particles with an average diameter of 9.22 ± 4.9 nm. Cytotoxicity assays indicated an IC₅₀ of 7.7 µg/mL. SEM analyses showed that eggs in the control group maintained intact morphology, with no apparent deformities. In contrast, exposure to AgNPs induced pronounced structural alterations, including marked wrinkling, surface erosion and shell collapse, suggesting disruption of multiple layers. Albendazole alone produced deep linear fissures consistent with internal metabolic failure, though with minimal external erosion. The combined treatment with AgNPs and albendazole resulted in severe degradation. These findings demonstrate that AgNPs exhibit significant ovicidal activity and may serve as effective adjuvants to enhance the action of conventional anthelmintics against highly resistant helminth eggs. Full article

To investigate the influence of particle characteristics on wear in slurry pump flow-through components, this study established a computational fluid dynamics-discrete element method (CFD-DEM) coupled with the Archard wear model for numerical simulation of solid-liquid two-phase flow characteristics and wear mechanisms within the pump. Focusing on the correlation between wear contour distribution and particle collision frequency, the study systematically analyzed the influence mechanisms of particle concentration, size distribution, and shape on wear patterns within the pump. The reliability of the coupled model was validated through external characteristic tests. Results indicate that wear severity on both the impeller and volute increases significantly with rising particle concentration, while wall particle collision frequency exhibits a positive correlation with concentration. Particles of 1.5 mm diameter cause the most severe localized wear on the impeller, whereas the presence of mixed particles partially mitigates the wear effect of larger particles. Both total and localized wear on the volute peak at a particle diameter of 1 mm. Low-sphericity particles intensified overall wear on both the impeller and volute; while high-sphericity particles reduced overall wear, they induced more severe localized wear on the impeller. Volute localized wear was most pronounced at a sphericity of 0.84. This study elucidates the mechanism by which particle characteristics influence wear on slurry pump flow-through components, providing a theoretical basis for optimizing slurry pump design. Full article

This study investigates the influence of ore particle shape on the wear behavior of ball mill liners using the Rocky-DEM software. A simulation model of a laboratory-scale ball mill was established to analyze the wear patterns of liners under three different ore particle shapes: polyhedron, ellipsoid, and sphere. The results indicate that while the overall motion patterns of the charge showed minor differences across particle shapes, significant variations were observed in flowability, with the polyhedral system exhibiting the lowest fluidity. Particle shape had a negligible impact on translational velocity but a substantial effect on rotational velocity. Regarding liner wear, the polyhedral system generated significantly higher wear compared to the spherical and ellipsoidal systems. The polyhedral system also exhibited the highest shear stress, identifying shear stress as the core factor dominating liner wear. The wear-time curves for individual liners in both radial and axial directions displayed a stepwise increase, suggesting that wear is primarily concentrated in the toe region. Full article

This work used activated carbon material obtained by chemical activation of abundantly available agricultural sunflower waste residues to remove metol (4-(methylamino) phenol sulfate, MTL) from aqueous solutions. The adsorbent structure was characterized using SEM-EDS and FT-IR spectroscopy. A modified screen-printed carbon electrode (SPCE) with gold nanoparticles synthesized using the Laser Ablation Synthesis in Solution (LASIS) method was used to detect MTL. The successful LASIS formation of gold nanoparticles was confirmed by the specific dark burgundy–red color. TEM measurements showed uniform pseudo-spherical particles with an average diameter of 7.9 ± 0.2 nm. The modified electrode showed improved electrochemical activity, which was confirmed by comparing it with an unmodified electrode using cyclic voltammetry and electrochemical impedance spectroscopy. The modified electrode was subsequently used to optimize the MTL detection conditions. UV–Vis spectroscopy was used to optimize the adsorption conditions, with the optimal values for pH and contact time found to be 8 and 120 min, respectively. The electrochemical detection of MTL was performed using differential pulse voltammetry, and the linear calibration range was established for concentrations ranging from 0.73–49.35 µM. The obtained limits of detection (LOD) and quantification (LOQ) were 0.06 µM and 0.2 µM, respectively. The efficiency of MTL removal was 100% after a contact time of 1 min and remained at 100% after 120 min. Full article

Plant-derived exosome-like extracellular vesicles (PELVs) have recently emerged as novel bioactive materials. Although members of the Orchidaceae family have been reported to possess various biological activities and are widely used as cosmetic ingredients, no studies to date have investigated exosome-like extracellular vesicles derived from Phalaenopsis species. In the present study, we report for the first time a novel exosome-like extracellular vesicles preparation isolated from Phalaenopsis aphrodite (called Exorigin^® OR) and characterize its physical and biological properties. The purified vesicles exhibited a spherical shape surrounded by a bilayered membrane with an average particle size of approximately 98 nm and expressed a CD9 marker. Fluorescent labeling with BODIPY TR indicated that Exorigin^® OR can be internalized by cells. In in vitro assays, Exorigin^® OR alleviated hydrogen peroxide-induced damage in keratinocytes and inhibited melanin production in melanocytes, possibly associated with the downregulation of Tyrp1 expression as shown by qPCR analysis. Moreover, reconstructed human epidermis and cornea-like epithelium models demonstrated that Exorigin^® OR is non-irritant. Collectively, these findings suggest that Exorigin^® OR represent a promising and safe bioactive ingredient for promoting skin health in cosmeceutical applications. Full article