Search Results (2,778)

Contamination of water resources by organic pollutants is a major environmental issue. Utilizing photocatalytic materials for the degradation of these pollutants presents a viable strategy for environmental clean-up. This study introduces the synthesis of an organic/inorganic hybrid photocatalyst of β-cyclodextrin (β-CD)/reduced graphene oxide (rGO) and titanium oxide (TiO₂) nanoparticles. The nanocomposite was characterized by using FT-IR, XRD, SEM, and EDAX, and the photocatalytic activity was studied by measuring the photodegradation of methylene blue (MB) under simulated solar radiation. The synthesized nanocomposite showed excellent stability and performance, with up to 92% photodegradation of MB. To further enhance the photocatalytic activity, the synthesized nanocomposite underwent modification with Ag and Pt nanoparticles. Within 90 min, photodegradation rates of 100% and 97% for MB were attained with Pt and Ag nanoparticles that were loaded at 5 wt.%, respectively. The photocatalyst’s reusability was evaluated through multiple usage cycles. Additionally, the impact of functionalization on the band gap alteration of TiO₂ is reported. Full article

Anaerobic digestion (AD) plays an important role in the circular bioeconomy by converting organic waste into renewable methane and nutrient-rich fertilizer. However, consistent, high-quality biomethane production is hindered by four main factors: hydrolysis limitations, fluctuating feedstock quality, microbial instability, and the high cost/energy demand of purification. This review explores three key areas that improve biomethane production: (i) process intensification (pretreatments and advanced reactors), (ii) microbial regulation through additives, and (iii) biogas upgrading for pipeline use. Anaerobic digestion can be greatly improved by combining thermal or hybrid pretreatments, staged digestion, high-solids technology, and electrochemical systems. These methods speed up hydrolysis and help the system handle higher amounts of organic material more effectively. However, actual performance benefits depend on specific substrate characteristics, heat integration, and control complexity. Optimizing the C:N ratio, buffering capacity, and trace-element supplementation, while simultaneously diluting toxic inhibitors, makes co-digestion an effective and adaptable approach to enhancing anaerobic digestion processes. Additives like carbon, iron nanoparticles, enzymes, and buffers can optimize digestion, but their performance is highly dependent on dosage and substrate. Additionally, they lack validation in long-term, industrial-scale applications. Conventional physicochemical techniques continue to be standard for generating high-quality biomethane, but biological methanation and microalgal systems are playing a growing role in integrating Power-to-Gas technology and using CO₂ efficiently. Critical research needs to focus on four areas: (1) standardized reporting metrics, (2) AI-enabled monitoring and control, (3) coupled techno-economic and life-cycle analysis (TEA-LCA), and (4) long-term pilot or full-scale validation. Overall, comprehensive optimization of the entire flow is more effective than improving isolated parts. Full article

Arsenic contamination, mainly in the arsenate (As(V)) form, continues to pose a serious threat to groundwater quality worldwide due to its long-term stability and toxicity at very low levels. Herein, we demonstrate, for the first time, a three-dimensional graphene oxide-based nanocomposite composed of Cu nanoparticle-doped, amino-functionalized UiO-66 (Cu/UiO-66-NH₂) anchored on a graphene oxide framework (Cu/UiO-66-NH₂@GO) as a novel and efficient nanosorbent for the rapid removal of As(V) in groundwater-like solutions. The nanocomposite was characterized by SEM and HRTEM to confirm the hybrid structure and by XRD, N₂ adsorption–desorption isotherms, and XPS to investigate crystallinity, porosity, and surface chemistry. The derived material exhibited a highly dispersed morphology and performed rapid arsenate solid-phase extraction to attain equilibration within 10 min and was effective for a wide pH range of 2–11. The best fit for the kinetic profiles was provided by the pseudo-second-order model. Interestingly, the maximum adsorption capacity of 747.9 mg g⁻¹ at pH 6.8 was achieved, demonstrating the benefits of the complementary pairing of dispersive GO sheets and Zr-MOF adsorption domains with Cu-derived active sites. Mechanistically, the enhanced uptake is ascribed to a combination of effects, including electrostatic pre-concentration, ligand exchange, and inner-sphere complexation at metal-oxo nodes; spectroscopic analysis (XPS and FTIR) suggests that the majority of arsenate is immobilized via a strong Zr-O-As bond at coordinatively unsaturated Zr centers, which is in line with t-ZrO₂-like surface domains formed within the nanocomposite. The embedded GO support inhibits further framework interpenetration and enhances active site availability and mass transport, leading to fast and high-capacity arsenate capture in groundwater samples with related conditions. Taken together, this work presents a powerful design concept that integrates unique GO-supported, Cu-modified UiO-66-NH₂ with Zr-O binding motifs to afford high-rate remediation nanocomposites, providing an excellent platform for next-generation arsenate remediation materials. Full article

Hybrid nanofluids possess exceptional thermal conductivity, but one of the major concerns with nanoparticles is agglomeration. While the usage of surfactants or dispersants can be used to mitigate this issue, numerical investigation and sensitivity analyses can be more affordable when attempting to optimize and design a thermal device. The consideration of thermal radiation with conductive and convective heat transfer and appropriate nanoparticles may provide a greater solution without compromising the efficacy of hybrid nanofluids. In the present work, the concept of magnetohydrodynamics (MHD) is used to examine the impact of thermal radiation on a stable, two-dimensional, incompressible hybrid fluid consisting of nanoparticles (MWNCT)${\mathrm{-Fe}}_3{\mathrm{O}}_4$ and water flowing over a vertical surface. The flow is governed by established equations of fluid dynamics, which use the Rosseland diffusion model to incorporate radiation effects. The implicit finite difference (IFD) was used to solve the mathematical equations. Sensitivity analyses were conducted as functions of volume fraction, radiation and magnetic variables. This study also examines the streamlines and isotherm lines with respect to the volume fraction, radiation parameter and magnetic parameter of the heat source. The results indicate that for a fixed radiation parameter, increasing the nanoparticle volume fraction by up to $20\%$ leads to a reduction of approximately $37\%$ in the skin friction coefficient, while the corresponding Nusselt number increases by nearly $50\%$. Furthermore, the introduction of a magnetic field parameter significantly suppresses wall shear stress and modifies the thermal boundary layer thickness, demonstrating the competing interaction between Lorentz-force-induced momentum damping and radiation-enhanced thermal diffusion. These quantified trends highlight the sensitivity of coupled momentum and heat transport to combined magnetic and radiative effects in hybrid nanofluid systems. Full article

Drought stress severely limits maize growth and productivity worldwide. In this study, we examined the effects of foliar-applied carbon nanoparticles (CNPs) on morphological and physiological traits in maize plants exposed to drought stress for 25 days. Two maize hybrids, one drought-tolerant (LG 36745 PRO4) and one drought-sensitive (AG 8088 PRO2), were fertilized with 0 or 1.0 mL L⁻¹ of a CNP-based nanofertilizer at the V₂ growth stage and exposed to three drought levels: 0 MPa (control), −0.4 MPa (moderate stress), and −0.8 MPa (severe stress). The experiment followed a 2 × 2 × 3 factorial design (hybrid × CNP treatment × drought level) with four replicates. Results indicated that drought stress adversely affected most morphological and physiological traits, particularly in the drought-sensitive hybrid. However, foliar CNP application significantly alleviated the adverse effects of drought in maize plants under moderate and severe stress, primarily by preserving plant water status, enhancing water use efficiency, carboxylation efficiency, photosynthetic rate, and initial growth in challenging environments. These findings will provide the basis for future research on management practices adopted to control drought and ensure the development of modern and sustainable agriculture. Full article

Bio-based, biodegradable, and renewable polymers offer a promising alternative to traditional synthetic polymers derived from petroleum or other non-renewable resources. However, their use is limited by suboptimal properties and high costs. Incorporating sustainable reinforcements into the polymer matrix significantly improves biopolymer performance while preserving key properties, sustainability, and cost-effectiveness. Bio-based polymeric composites have emerged as a crucial category of biopolymers, playing a key role in advancing a sustainable, circular economy. This review provides an updated overview of bio-based polymer composites and nanocomposites, focusing on reinforcement strategies using natural nanofillers and engineered nanoparticles. We summarize key synthesis and processing methods, discuss structure–property relationships, and highlight recent advances in applications such as food packaging, biomedical devices, energy systems, environmental remediation, 3D printing, and supercapacitors. Polymer nanocomposites are versatile, with their performance depending on the type, size, and interactions between the fillers and the polymer matrix. Progress in metallic, ceramic, carbon-based, natural, and hybrid fillers has improved their properties. Using bio-based polymers and renewable fillers supports sustainability. Natural nanofillers derived from renewable sources and industrial byproducts offer a sustainable approach to developing high-performance, biodegradable nanocomposites. Smart nanocomposites can react to external stimuli by integrating specialized fillers that enhance their mechanical and mobility properties. Shape memory nanocomposites can be remotely activated—using heat, electricity, magnets, or light—enabling advanced applications. Finally, we address major challenges and outline future directions for scalable, circular-material solutions, drawing on perspectives from the circular economy and life cycle assessment (LCA). Full article

Selenium nanoparticles (SeNPs) represent promising bioactive agents due to their reduced toxicity and multifunctional biological properties. In this study, SeNPs were synthesized via an eco-friendly phytosynthesis approach using Curcuma longa extract, yielding curcumin-functionalized selenium nanoparticles (cur–SeNPs). The composites (cur–SeNPs), either in native extract form or isolated, were incorporated into siloxane hybrid matrices prepared by the sol–gel method from tetraethyl orthosilicate: dimethyldimethoxysilane precursors, with polyvinylpyrrolidone (PVP) as a structural modifier. The host matrices were differentiated by the ratios between the precursors of the siloxane network, 3:1 for CS0–CS4, respectively, 1:1 for CS5, modified with PVP in the case of CS2 and CS3. These were loaded with cur–SeNPs–T in the cases of CS1, CS2, CS5 or with cur–SeNPs for CS3 and CS4. FTIR, XRD, SEM, and EDX analyses confirmed the formation of amorphous siloxane networks with well-dispersed SeNPs (up to ~12 wt%). PVP incorporation generated ordered mesoporous structures, increasing total pore volume sixfold and enlarging the average pore diameter to 9.26 nm. Studies about selenium ion release demonstrate that mesoporosity significantly enhances diffusion-controlled release. Antimicrobial assays against Staphylococcus aureus, Escherichia coli, and Candida albicans reveal a synergistic effect between curcuminoids and SeNPs, particularly in matrices with higher nanoparticle loading. The sol–gel technique for obtaining hybrid materials is very versatile regarding the supports on which the resulting materials or the compounds hosted in these host networks can be deposited. The dynamics of the development of hybrid materials is also reflected in the multitude of applications in various fields such as bio-medical, electronics, agriculture or food. Results obtained in this work highlight the potential of the developed systems for antimicrobial coatings on glass substrates and targeted delivery applications. Full article

Hybrid supramolecular–nanocomposite hydrogels based on polyethylene glycol (PEG), β-cyclodextrin–adamantane host–guest interactions, and silica nanoparticles represent an important class of hierarchical soft materials with tunable viscoelastic and transport properties. This review critically analyzes recent progress in cyclodextrin–silica hybrid PEG hydrogels, focusing on the mechanistic coupling between stiffness, stress relaxation, and molecular transport arising from the interplay between reversible supramolecular crosslinks and nanoparticle-induced confinement effects. Particular attention is given to how host–guest exchange kinetics regulate dynamic bond rearrangement and affinity-mediated retention of hydrophobic cargo, while silica nanoparticles enhance mechanical reinforcement and modify diffusion pathways through tortuosity and interfacial polymer–particle interactions. The analysis highlights how nanoparticle size, loading level, and surface functionalization influence relaxation spectra and network topology, as well as how environmental stimuli may affect supramolecular bond stability and overall material performance. Comparison with alternative inorganic fillers and mesoporous silica architectures further clarifies the specific advantages of silica in achieving balanced mechanical stability and controlled transport behavior. Overall, current evidence indicates that hybrid CD–silica networks enable partial decoupling of stiffness, relaxation dynamics, and diffusion, although complete independence remains constrained by fundamental polymer physics relationships. These insights support the development of predictive structure–property frameworks for advanced biomedical and controlled release applications. Full article

Phytochemicals have attracted considerable attention as therapeutically relevant bioactive compounds due to their diverse pharmacological activities, including anti-inflammatory, antioxidant, anticancer, and metabolic regulatory effects. However, their clinical translation is frequently hindered by unfavorable pharmaceutical properties such as poor aqueous solubility, chemical instability, rapid metabolism, and limited bioavailability. These challenges have constrained the reproducibility and therapeutic reliability of phytochemical-based interventions. In this context, nanotechnology-enabled delivery systems have emerged as effective strategies to overcome the intrinsic limitations of phytochemicals and enhance their biological performance. This review provides a comprehensive overview of recent advances in nanotechnology-based delivery platforms for phytochemicals, with emphasis on lipid-based nanocarriers, polymeric nanoparticles, nanoemulsions and self-nanoemulsifying drug delivery systems, inorganic and hybrid nanocarriers, as well as hydrogel-based and transdermal delivery systems. We discuss how rational nanocarrier design improves solubility, stability, pharmacokinetics, cellular uptake, and tissue targeting, thereby enhancing therapeutic efficacy across multiple disease areas. In addition, critical safety, toxicity, manufacturing, and regulatory considerations that influence translational potential are addressed. By adopting a delivery-centered perspective, this review highlights current challenges and future opportunities in nano-phytomedicine and underscores the importance of integrating nanotechnology, biological insight, and regulatory-conscious development to advance phytochemicals toward clinically viable therapeutic applications. Full article

ZnFe₂O₄ is a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity, but its practical use is limited by poor conductivity and large volume changes during cycling. To address these issues, a ZnFe₂O₄-reduced graphene oxide (Z-F-rGO) composite was fabricated via solvothermal synthesis and calcination, with Z-F nanoparticles in situ anchored on rGO sheets. Characterizations (XRD, Raman, XPS, SEM, TEM) confirm the formation of highly crystalline spinel Z-F with good interfacial contact with rGO. The Z-F-rGO electrode shows excellent electrochemical performance, maintaining a reversible capacity of 985.4 mA h g⁻¹ after 100 cycles at 0.5 A g⁻¹, significantly higher than the 498.2 mA h g⁻¹ of the Z-F. At 1.0 A g⁻¹, the Z-F-rGO electrode retains 959.4 mA h g⁻¹ after 300 cycles, while the Z-F electrode shows a capacity of 441.3 mA h g⁻¹. CV analysis indicates good reversibility, while EIS and GITT reveal reduced charge-transfer resistance and enhanced Li⁺ diffusion. This work provides an efficient strategy for scalable Z-F-rGO composites, offering a promising approach for high-performance LIB anodes. Full article

Iron oxide nanoparticles have emerged as multifunctional compounds with prominent potential in cancer theranostics, particularly in photothermal therapy (PTT) and photodynamic therapy (PDT). Their unique electronic and crystal structures, such as the dispersion of Fe²⁺ and Fe³⁺ ions and d-orbital splitting, contribute to their magnetic and catalytic properties. In PTT, Fe₃O₄ nanoparticles exhibit moderate near-infrared (NIR) absorption and photothermal conversion efficiency, which can be enhanced through adjustments in particle size, surface modification, and combinations with other components. In PDT, Fe₃O₄ nanoparticles demonstrate intrinsic peroxidase-like catalytic activity, facilitating Fenton and photo-Fenton reactions that generate reactive oxygen species (ROS), including hydroxyl radicals (^•OH), thereby amplifying oxidative stress in cancer cells. These nanoparticles can also function as carriers for photosensitisers (PS), promoting targeted delivery and enhanced ROS generation. Multifunctional nanomaterials that integrate Fe₃O₄ with other therapeutic agents and targeting ligands have demonstrated synergistic antitumour effects through amplified photothermal, photodynamic, chemodynamic, and chemotherapeutic mechanisms. Despite certain drawbacks, such as relatively low NIR absorption and challenges in optimising delivery and light activation, ongoing improvements in Fe₃O₄-based nanoplatforms present significant potential for enhancing treatment outcomes and the precision of cancer therapy. This article systematically explores the synergistic role of Fe₃O₄ nanoparticles in PTT and PDT, encompassing their magnetic and catalytic characteristics. Additionally, it focuses on multifunctional hybrid nanoplatforms that combine Fe₃O₄ with targeting or imaging agents, highlighting their potential to enhance therapeutic precision. Full article

Nano- and microplastic contamination poses a growing challenge to aquatic environments, driving the need for efficient and sustainable removal technologies. In this study, carbon–silica hybrid nanoparticles (CSNPs) were synthesized from rice husk-derived black liquor via controlled lignin–silica self-assembly followed by thermal carbonization, providing a waste-recycling biorefinery route for value-added material production. Structural characterizations revealed that carbonization generates a hierarchically porous carbon–silica hybrid with enhanced surface area. The CSNPs exhibited rapid and size-dependent adsorption toward nano- and microplastics (200–1000 nm), with optimal performance observed for 500 nm particles. Microscopic observations further demonstrated a size-adaptive capture mechanism, involving pore filling and surface adsorption for nanoplastics and aggregate-assisted encapsulation for larger microplastics. This study highlights CSNPs as low-cost and effective adsorbents for broad-spectrum plastic removal while offering a sustainable pathway for the high-value utilization of black liquor and rice husk biomass in water purification applications. Full article

This study presents a statistically optimized protocol for the green synthesis of gold nanoparticles (Au NPs) using aqueous Kalanchoe pinnata leaf extract (AKPLE). An integrated experimental strategy, transitioning from preliminary one-factor-at-a-time (OFAT) screening to a five-factor Box–Behnken Design, was employed to model and simultaneously optimize two critical optical responses derived from surface plasmon resonance: the peak position (λ_max) and its absorbance intensity. Highly predictive quadratic models (R² > 0.97) revealed that synthesis outcomes are governed by significant nonlinear curvature, with minimal interaction effects. Multi-response optimization via a desirability function identified a harmonized set of conditions (HAuCl₄: 0.44 mM, AKPLE: 3.50% v/v, temperature: 80.6 °C, pH: 7.2, time: 66.7 min) predicted to minimize λ_max at 540 nm while maximizing absorbance to 0.61. Synthesis under these optimized conditions successfully produced spherical, crystalline Au NPs, as confirmed by characterization (average TEM size: 26.3 ± 4.1 nm; zeta potential: –30.45 mV). This work demonstrates that a hybrid OFAT-RSM approach is superior for the precise, multivariate optimization of plant-mediated Au NP synthesis, providing a validated and scalable framework to balance nanoparticle size and plasmonic intensity—an outcome unattainable through conventional OFAT methods. Full article

Printed electronics have emerged as a versatile manufacturing platform for next-generation biosensors, enabling on-demand and low-cost fabrication of functional devices on flexible, stretchable, and unconventional substrates. One major challenge in this field lies in the sintering of printed features, as conventional high-temperature processing is incompatible with polymeric substrates and thermally sensitive biological components. Low-temperature sintering inks, typically processed below 200 °C or even at room temperature, have become a critical enabling technology for bio-integrated electronics. This review provides an overview of the current state-of-the-art and key challenges associated with low-temperature sintering inks for printed bioelectronics. We discuss inks based on metal nanoparticles, metal–organic decomposition precursors, metal oxides, chalcogenides, and hybrid material systems. The emphasis is on how ink chemistry, ligand selection, and precursor structure govern rheology, stability, and sintering behavior. In addition, key low-temperature sintering and curing strategies, including thermal, photonic, laser, plasma, microwave, and chemical sintering, are compared in terms of energy delivery, densification mechanisms, and substrate compatibility. Finally, we outline emerging directions towards low temperature and room-temperature sintering inks, and sustainable biobased ink formulations, and discuss their applications for wearable, implantable, and soft biosensing platforms. Full article

Background/Objectives: Oral diseases remain among the most prevalent noncommunicable conditions worldwide, with biofilm-driven dysbiosis playing a central role in dental caries, gingivitis, periodontitis, and oral candidiasis. Curcumin has attracted considerable interest because of its anti-inflammatory, antioxidant, antimicrobial, and regenerative properties. However, its clinical use remains limited by poor water solubility, chemical instability, rapid metabolism, and low bioavailability. This review aimed to provide a comprehensive analysis of curcumin-based nanoformulations for oral health applications, with emphasis on their mechanistic actions, antibiofilm activity, and translational relevance. Methods: This review examined representative nanocarrier systems developed for curcumin delivery in oral health. These included polymeric nanoparticles, nanomicelles and nanoemulsions, solid lipid nanoparticles and nanostructured lipid carriers, nanogels, hydrogels, mucoadhesive films, and metallic or hybrid nanosystems. The analysis focused on molecular mechanisms of action, antimicrobial and antibiofilm effects against major oral pathogens, and key translational challenges. Results/Findings: Across the reviewed studies, nanoformulations consistently improved curcumin solubility, stability, tissue penetration, mucosal retention, and controlled release. Mechanistically, they enhanced anti-inflammatory activity through inhibition of nuclear factor kappa B (NF-κB), strengthened antioxidant defenses via the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) axis, supported tissue repair and osteogenic responses, disrupted oral biofilms, and modulated local immune responses. Antimicrobial activity was reported against Streptococcus mutans, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Candida albicans, with reduced exopolysaccharide production, impaired adhesion, and improved biofilm penetration. Conclusions: Curcumin-based nanoformulations represent promising adjunctive platforms for oral healthcare. However, their clinical translation still requires improved stability in the oral-environment standardized manufacturing and characterization, rigorous safety evaluation, and well-designed controlled clinical studies. Full article