Search Results (361)

This study aims to investigate the short-term dynamics of agricultural landscapes using AI-supported multi-temporal land use/land cover (LULC) data. The Finike district, located within the Mediterranean climate zone, was selected as the study area, and 10 m spatial resolution ArcGIS Living Atlas LULC raster datasets for the years 2017 and 2024 were used. Spatial dynamics of agricultural areas were analyzed using Fragstats by quantifying changes in area and dominance (CA, PLAND), fragmentation and patch density (NP, PD), spatial integrity and largest patch structure (LPI), shape complexity (PARA_MN), and aggregation–connectivity patterns (CLUMPY, AI), thereby providing a comprehensive assessment of fragmentation, dispersion, clustering, and landscape cohesion over time. The analyses were conducted specifically for the agricultural class for both class-level and landscape-level metrics. The findings indicate that agricultural areas, which covered approximately 3128 hectares in 2017, decreased to 2643 hectares by 2024, as shown in the quantitative results of landscape metrics, accompanied by a pronounced increase in fragmentation. The increase in the number of patches, the decrease in mean patch size, and the rise in patch density demonstrate that the agricultural landscape has transformed into a more fragmented and irregular structure. The results further reveal a weakening of spatial integrity in agricultural areas, suggesting increased pressure from land use change processes, particularly urban expansion, in the study area, and highlighting potential risks for land management, agricultural sustainability, and ecological functions. Overall, the study highlights that the integrated use of high-resolution, AI-supported LULC data and landscape metrics provides a robust and effective framework for monitoring short-term dynamics in agricultural landscapes and supporting evidence-based planning processes. Full article

The hydrogen evolution reaction (HER) plays a central role in electrochemical hydrogen production and requires catalysts that combine high activity with reduced noble metal usage. In this work, palladium nanoparticles (PdNPs) were deposited onto silver nanowire-modified graphite electrodes (Pd/AgNW/C) to investigate the influence of Pd loading on HER kinetics and catalytic efficiency. The electrodes were prepared by constant-current electrodeposition and characterized using polarization measurements and electrochemical impedance spectroscopy (EIS). The direct current (DC) results showed a pronounced enhancement of HER activity in the presence of Pd, while the highest mass-specific activity was observed at low Pd loadings. Increasing the Pd content further increased the overall current but reduced the catalytic efficiency when normalized to the Pd mass. EIS measurements revealed two contributions to the impedance response associated with processes occurring on different timescales. With increasing cathodic overpotential, both the charge transfer resistance and the low-frequency resistance decreased markedly, indicating accelerated reaction kinetics. The combined DC and alternating current (AC) analyses suggest that the silver nanowire network facilitates efficient electron transport and promotes a favorable dispersion of Pd nanoparticles at low loadings, enabling efficient HER catalysis with reduced noble metal usage. Full article

Neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) represent some of the most complex and therapeutically challenging disorders in modern medicine. Despite decades of research, the traditional one drug–one target paradigm has largely failed to deliver disease-modifying therapies. Increasing evidence suggests that these complex diseases arise from interconnected pathological networks involving protein aggregation, oxidative stress, mitochondrial dysfunction, neuroinflammation, and synaptic loss. In this context, natural products (NPs) have re-emerged as a promising pipeline for next-generation therapeutics. Unlike conventional small molecules, NPs inherently exhibit polypharmacology, targeting multiple pathways simultaneously. Recent advances (2019–2026) demonstrate a paradigm shift, from crude NPs and single-mechanism compounds toward engineered derivatives, network pharmacology, and multi-target drug design. Using AD and PD as case studies, this review critically evaluates how NPs are redefining drug discovery by highlighting key emerging NPs, translational strategies, and future directions. Full article

Electrolysis of water is a promising emission-free approach of hydrogen production, making water electrolyzers important for many renewable energy systems. Electrochemical electrodes enriched with nanocatalysts can significantly advance such technologies, but the use of nanomaterials, deployed as packed powders or painted films, is generally limited by durability and reusability challenges. To overcome these deficiencies, we have fabricated hierarchical hybrid electrode (HHE) monoliths comprising carpet-like arrays of multiwalled carbon nanotubes covalently bonded to porous reticulated carbon foams that are further functionalized with strongly attached nanocatalysts. This paper presents our investigation of HHE materials with CNT carpets and palladium nanoparticle (PdNP) catalysts in two key electrolysis reactions: hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Their performances in different electrolytes have been evaluated using cyclic voltammetry, linear sweep voltammetry and Tafel analysis. This architecture provided multi-faceted advantages, and the contribution of each nanocomponent in the monolith has been analyzed. The presence of Pd-NP in the HHE also improved the electrode’s tolerance to Cl⁻ ions, which is very promising for saline water electrolysis. These studies indicate that the HHE architecture of electrochemical electrodes can be a versatile and tunable option for future electrochemical systems relevant to renewable energy applications. Full article

In this study, a waste-to-resource route for water remediation is presented by supporting Pd and Cu nanoparticles (NPs) on hydrochar (HC) derived from spent coffee grounds (SCG). Unlike conventional noble-metal catalysts, HC was first produced via hydrothermal carbonization of SCG, followed by a completely green, tannic acid-assisted reduction step that simultaneously deposits Pd and Cu NPs without toxic reductants or organic solvents. The resulting catalysts were evaluated for catalytic reduction of 4-nitrophenol (4-NP) and for antibacterial activity against Escherichia coli (E. coli; BL21) and Staphylococcus aureus (S. aureus), including biofilm inhibition. Among formulations, the bimetallic catalyst containing approximately equal proportions of Pd and Cu (HC@Pd_0.5Cu_0.5) achieved the fastest 4-NP reduction, completing the reaction in ~3 min, with an apparent first-order rate constant of 1.35 min⁻¹ and a total turnover frequency of 483.6 h⁻¹. Notably, Cu incorporation enhanced antibacterial performance, with the Cu-rich variant (HC@Pd_0.25Cu_0.75) achieving the strongest inhibition (MICs of 1.25 mg/mL against E. coli and 2.5 mg/mL against S. aureus) and effective biofilm suppression. This dual-action catalyst, derived entirely from waste through green methods, advances circular-economy principles and green chemistry by simultaneously tackling chemical pollutants and microbial contaminants in water, thereby contributing to SDG 6 (Clean Water and Sanitation). Full article

Green synthesis of nanoparticles has become one of the most popular research areas in recent decades due to its environmentally friendly nature and the minimization of harmful chemical by-products. This review focuses on the mechanism of palladium nanoparticle (PdNP) biosynthesis using bacteria, fungi, algae, and plants, and their potential biological activities, such as antibacterial, anticancer, antioxidant, and other properties, with the aim of their further biomedical applications. The role of various biomolecules in these processes is also discussed. Full article

Nanotechnology combined with photodynamic therapy (PDT) has been explored to enhance antitumor and antimicrobial photobiological activity. Aluminum phthalocyanine chloride (Al-Pc-Cl), with or without magnetic nanoparticles (MagNPs), was incorporated into polymeric nanoparticles (PNPs) to improve the PDT for treating tumors and infectious diseases. Three batches of the nanoparticles (MagNPs, PNPs-PS and PNPs-PS-MagNPs) were developed and characterized in terms of size, PdI, morphology by TEM, release study, and antitumor (against A549 cells) and antimicrobial (against MRSA and C. albicans) photobiological activity. The developed nanoparticles were nanometric in size, with MagNPs, PNPs-PS, and PNPs-PS-MagNPs showing 33.6, 186.9, and 333.5 nm, respectively, maintained the magnetic properties (for MagNPs and PNPs-PS-MagNPs), and provided slow and sustained release of the photosensitizer. PNPs-PS and PNPs-PS-MagNPs showed excellent antitumor photobiological activity with cell viabilities of 42 and 34%, respectively, and were not cytotoxic in the dark, with cell viabilities above 70%. PNPs-PS showed strong antibacterial activity against MRSA with an IC₅₀ of 8.26 μg/mL, which was lower to free Al-Pc-Cl with an IC₅₀ of 14.22 μg/mL after I radiation. The results of the antifungal photobiological activity against C. albicans were excellent, with IC₅₀ values of 3.75 and 3.5 μg/mL for PNPs-PS and PNPs-PS-MagNPs, respectively, values which were significantly lower with p < 0.05 than free PS (IC₅₀ > 30 μg/mL) after irradiation with light and fluconazole (IC₅₀ > 30 μg/mL), the reference antifungal agent. PNPs-PS showed promising results regarding antitumor, antibacterial, and antifungal photobiological activity. However, PNPs-PS-MagNPs showed weak results for antibacterial photobiological activity against MRSA but with promising results for tumor cells and C. albicans. Full article

Bimetallic nanoparticles have garnered significant attention in scientific literature due to their diverse applications and unique properties. Concurrently, green synthesis methodologies have emerged as environmentally friendly alternatives, reducing the ecological footprint of nanoparticle production. In this study, the efficient synthesis of Au-Pd bimetallic nanoparticles is presented, utilizing Aspalathus linearis (Burm.f.) R. Dahlgren, commonly known as green rooibos (GR), and its pure bioactive compound, Aspalathin (ASP). Integrating ASP as a pure compound into the green synthesis process offers precise control over nanoparticle characteristics, including size, morphology, and composition. Interestingly, the total extract forms an Au-Pd nanoparticle alloy, while aspalathin forms core–shell nanoparticles. Furthermore, cytotoxicity testing was carried out on selected cell lines to assess their impact on cell viability. The cytotoxicity test on cell lines and cellular uptake analysis demonstrated that none of the tested samples exhibited significant cytotoxic effects. ASP-conjugated bimetallic increased the uptake of the NPs by the cells more than the total extract. The results demonstrated that the Au-Pd bimetallic nanoparticles hold promise for biomedical applications, owing to their enhanced biocompatibility and tailored properties. Full article

Background: Mitochondrial dysfunction in microglia is an important pathogenic factor inducing the onset of Parkinson’s Disease (PD). To address this challenge, a novel hierarchical nano-delivery system was developed to deliver a PD therapeutic agent, wedelolactone (WED) to modulate mitochondrial dysfunction. Methods: The nano-delivery system (WED@RBCm-B6&RAP12-NPs) was coated with red blood membrane (RBCm) to avoid immune clearance and conjugated with the BBB-penetrating peptide CGHKAKGPRK (B6) and the microglia targeting peptide EAKIEKHNHYQK (RAP12). Results: The experimental results demonstrated that this novel nano-delivery system could increase its half-life in blood circulation effectively via evading immune recognition and clearance and enhanced its brain distribution by synergistic effect of B6 and RAP12. By specifically targeting microglia in PD mouse brain, the system increased pyruvate dehydrogenase (PDH) activity, leading to mitochondrial structural repair, reduced secretion of pro-inflammatory cytokines, and improved the inflammatory microenvironment. Conclusions: The result first designed and synthesis a dual targeting drug delivery system WED@RBCm-B6&RAP12-NPs which significantly alleviated mitochondrial dysfunction and warranted further study to develop therapeutic agent for PD treatment. Full article

Background: Nanoparticles are a promise for wound-healing therapies. However, its lack of efficacy/safety represents a real challenge for therapeutic use. Objectives: To overcome these problems, the ethanolic extract of Casimiroa edulis leaves, previously reported for its anti-inflammatory, antibiotic, and antioxidant activities, was characterized by FIA-ESI-FTICR-MS and encapsulated in biodegradable nanoparticles for potential wound-healing therapies. Methods:Casimiroa edulis-loaded nanoparticles (CE-NP) were prepared using the rapid emulsion-diffusion method and characterized by their particle size distribution, molecular interactions, charge, morphology, pH, physical stability, and antioxidant and occlusive effects. Results: A total of 40/34 ions in positive/negative electrospray ionization modes were obtained from the extract exploration analysis and were putatively annotated by accurate mass against databases with an error tolerance ≤10 mDa. The most abundant compounds showed the following order: tetramethylscutellarein > rutin > S-usnate > lactose > eugenol derivative > rotenone. While polyphenols predominated, carbohydrates, depsidones/other phenolics, etc., were also detected. The solid/spherical nanoparticles observed by TEM were obtained with a blend of acetone:methyl ethyl ketone (75:25) as the organic phase, producing a unimodal particle size (169.30 ± 1.30 nm; PdI = 0.08 ± 0.03). The encapsulation/loading percentages were 57 ± 0.74/1.62 ± 0.02%, ensuring an entrapment of half the extract, as observed in the FTIR studies. The light backscatter profiles show minimal differences, indicating physical stability correlated with the Z potential (−9.45 ± 1.73 mV). The antioxidant activity of the extract/nanoparticles at 40 µg/mL was 17.27 ± 2.86/16.73 ± 1.28 μg/mL, two-fold higher than that previously reported for sapote seeds. Conclusions: Biodegradable CE-NP with suitable characteristics were obtained for the first time, representing a preliminary proposal for wound healing. Efficacy studies are required. Full article

Background/Objectives: Research on noble metal nanoparticles (NPs) has increased over the past three decades, with advancements in synthesis techniques refining their physicochemical characteristics, including size, shape, and surface chemistry. Bimetallic NPs (BNPs) offer synergistic properties contributed by both metals. Gold (Au) and palladium (Pd) NPs possess low toxicity, high biocompatibility and loading, ease of synthesis and surface modification. Doxorubicin (DOX) and 5-fluorouracil (5-FU) are potent chemotherapeutic drugs but are rapidly metabolised in the body, producing severe side effects, limiting their use. Hence, innovative strategies to mitigate this is needed. Methods: In this study, AuPd NPs in a core-shell formation were chemically synthesized. The AuPd NPs were conjugated to 5-FU and DOX-encapsulated CS complexes and decorated with the targeting moiety transferrin (Tf). Results: Transmission electron microscopy and nanoparticle tracking analysis confirmed that the BNPs were spherical, with an average size of 73.4 nm. Functionalized BNPs were able to encapsulate more than 70% of 5-FU and DOX, resulting in a controlled drug release profile at pH 4.2. Cytotoxicity levels in human cancer cells, HeLa (cervical carcinoma) and MCF-7 (breast adenocarcinoma), as well as in non-cancer HEK293 (embryonic kidney) cells, revealed that the Tf-targeted nanocomplexes were HeLa cell-specific, with no significant cytotoxicity in the HEK293 cells. Tf-mediated cellular uptake was confirmed by receptor competition studies in the HeLa cells. Apoptosis and oxidative stress analysis confirmed cell death by apoptosis, consistent with the action of 5-FU and DOX. Conclusions: This study highlighted the potential of this BNP-nanocomplex as a suitable vehicle for drug delivery. Full article

Background/Objectives: The biogenic synthesis of silver nanoparticles (AgNPs) is a promising alternative method, driven by the presence of metabolites in plant matrices capable of acting as reducing and stabilizing agents. Seasonality is a key factor that influences the phytochemical composition of plants and can directly impact the yield, physicochemical characteristics, stability, and bioactivities of the obtained AgNPs. This study aimed to synthesize AgNPs using aqueous extracts from Paullinia cupana leaves collected during dry and rainy seasons, prepared by two different methods (agitation or infusion), to evaluate the impact of these variables on the biosynthesis and properties of the nanostructures. Methods: The extracts were characterized by UHPLC-HRMS/MS, and their total phenolic compound (TPC) content and antioxidant potential against DPPH and ABTS radicals were determined. The AgNPs were characterized by UV/Vis spectrophotometry, dynamic light scattering (DLS), zeta potential (ZP), nano-particle tracking analysis (NTA), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). Results: The metabolic profile results showed a predominance of alkaloids and flavonoids in all extracts, with greater phytochemical diversity in samples prepared by infusion. TPC indicated superior phenolic extraction in extracts prepared by infusion during the rainy season, correlating with greater antioxidant potential via the elimination of free radicals. The evolution of AgNP synthesis was accompanied by a gradual change in the color of the suspensions and the formation of plasmon bands between 410 and 430 nm, characteristic of spherical AgNPs. The nanostructures presented hydrodynamic diameters between 37.49 and 145.5 nm, PdI between 0.222 and 0.755, and Zeta potential between −11.3 and −39.9 mV, suggesting satisfactory colloidal stability. Morphological analyses revealed predominantly spherical particles with average diameters ranging from 33.61 to 48.86 nm and uniform distribution, while EDX spectra confirmed the presence of silver. Conclusions: Thus, our results demonstrate that both seasonality and the method of extract preparation influence the phytochemical composition and, consequently, the morphology, stability, and optical properties of AgNPs, with subtle emphasis on collections made during the rainy season and extracts prepared by infusion. Such knowledge contributes to the advancement of more reproducible and purpose-oriented syntheses in the field of green nanotechnology, enabling applications in various sectors. Full article

Metal nanoparticles (NPs) with enzyme-mimicking activities, known as nanozymes, are being actively explored for biomedical and analytical applications. Enhancing their catalytic activity and metal utilization efficiency is crucial for advancing these technologies. Here, we report an aqueous-phase, room-temperature synthesis of tetra-metallic Au@Ag-Pd-Pt NPs that exhibit superior peroxidase-like activity compared to their mono-, bi-, and trimetallic counterparts. The synthesis involves a sequential, seed-mediated approach comprising the formation of Au NP seeds, the overgrowth of a Ag shell, and the galvanic replacement of Ag with Pd and Pt ions. We systematically investigated the effects of the Au core diameter (15, 40, 55 nm), Ag precursor concentration (50–400 µM), and the Pd-to-Pt ratio on the optical and catalytic properties. By changing the particle composition, we were able to tune the absorbance maximum from 520 nm to 650 nm while maintaining high extinction coefficients (10⁹–10¹⁰ M⁻¹cm⁻¹) comparable to that of the initial Au nanoparticles. Mapping of chemical element distributions in the nanoscale range confirmed a core–shell–shell architecture with surface-enriched Pd and Pt. This structure ensures the surface-exposed localization of catalytically active atoms, yielding a more than 10-fold improvement in specific peroxidase-like activity while utilizing up to two orders of magnitude less Pt and Pd than bimetallic particles. The synthesized NPs thus combine high catalytic activity with tunable optical properties, making them promising multifunctional labels for biosensing. Full article

This study presents a sustainable and efficient method for fabricating core–shell structured palladium catalysts using a bacterial template and sol–gel synthesis. This synthesis aligns with green chemistry principles by minimizing waste and enhancing resource efficiency. Our results demonstrate that the bacterial template effectively stabilizes Pd nanoparticles (NPs), preventing significant agglomeration during synthesis and subsequent calcination under different atmospheres and final temperatures. The catalyst samples were characterized by SEM, TEM, XRD, and TGA. The 1 wt% Pd/R@SiO₂ catalyst exhibited high activity in the Suzuki–Miyaura cross-coupling reaction, achieving competitive yields. Furthermore, the catalyst demonstrated a stable performance over five consecutive cycles. This work underscores the potential of biotemplated synthesis as a versatile and eco-friendly platform for producing high-performance, tunable catalysts. Full article

In this work, a novel approach for the catalytic reduction of 4-nitrophenol to 4-aminophenol using sodium borohydride is proposed. It was shown that a continuous-flow microreactor system is an optimal tool for PdNP synthesis with dimensions of 3.0 ± 0.5 nm, as well as the performance of catalytic tests with high process efficiency, while keeping a high level of safety. The results obtained from the microreactor system allowed for 100% conversion to 4-aminophenol and were compared to processes carried out in a batch reactor, as well as to a hybrid system which was a combination of a microreactor (synthesis of PdNPs) and batch reactor (catalytic test). These investigations were enhanced by kinetic studies, for which a stopped-flow spectrophotometer was applied due to the extremely high rate of the reaction, i.e., formation of PdNPs (2.1 s), as well as to measure in situ the rate of the heterogeneous catalytic process. To visualize the progress of the heterogeneous reaction more precisely, color coding based on transmittance measurements was employed. Furthermore, to deepen the understanding of the process, a detailed mechanism supported by DFT calculations for the conversion of 4-nitrophenol to 4-aminophenol in the presence of PdNPs was proposed. Full article