Although photodynamic therapy selectively eradicates tumours via light-triggered reactive oxygen species (ROS) generation, conventional photosensitizers suffer from poor solubility and a reliance on short-wavelength light with limited tissue penetration. To address this, we developed a redox-responsive polymeric nanocarrier through free-radical polymerization of a pre-assembled micellar ensemble. This ensemble formed spontaneously in aqueous solution by encapsulating the hydrophobic photosensitizer meso-tetrakis(p-hydroxyphenyl)porphyrin within a core composed of the disulfide-containing monomer N,N'-bis(acryloyl)cystamine, while a viologen-functionalized resorcinarene cavitand anchored at the micelle surface, providing colloidal stability. Polymerization yielded core-shell nanoparticles with a glutathione-cleavable, disulfide-rich core and a viologen-decorated shell. In vitro investigations across a broad panel of six malignant and two non-malignant cell lines demonstrated low dark cytotoxicity and acceptable blood compatibility, with hemolysis remaining below 10%. In the dark, the formulation induced a non-lethal, transient cytostatic effect driven by early-stage apoptosis. Crucially, upon 650 nm laser irradiation, the nanocarrier engaged powerful photodynamic activity, triggering a massive transition to late apoptosis and direct cell death, resulting in near-complete tumor cell eradication. ROS generation, subcellular localization, and programmed cell death mechanisms were confirmed by flow cytometry and fluorescence microscopy, establishing the developed redox-responsive system as an effective candidate for targeted photodynamic therapy.
In recent years, metallic Ti 3 C 2 T x MXenes have garnered considerable attention in the realm of gas sensors owing to their distinctive characteristics, including high conductivity, inherent hydrophilicity, and abundant surface termination groups. Nonetheless, Ti 3 C 2 T x -based sensing composites encounter challenges related to response/recovery time and low sensitivity, thereby limiting their applicability across diverse environmental conditions. Addressing these limitations, we present the synthesis of ZnO/Ti 3 C 2 T x nanocomposites via a facile method for gas sensing applications. The optimized composite exhibits a notable response of around 6.1% to 5 ppm NO 2 , coupled with remarkable selectivity at ambient temperatures. Moreover, the sensor demonstrates exceptional reproducibility across multiple testing iterations. The observed enhancement in gas sensing performance is attributed to the abundance of oxygen vacancies and surface functional groups within the ZnO/Ti 3 C 2 T x composites, which facilitate robust interactions with NO 2 molecules. These findings underscore the efficacy of ZnO/Ti 3 C 2 T x nanocomposites as a viable strategy for enhancing the gas sensing properties of Ti 3 C 2 T x -based sensors.
Nanotechnology offers innovative opportunities for developing functional materials with applications across biomedical and food-related fields. Among metallic and metal oxide nanostructures, niobium-based compounds have recently attracted attention due to their remarkable mechanical strength, corrosion resistance, thermal conductivity, and biocompatibility. In this study, niobium oxide nanostructures were synthesized through a green, cell-free approach using supernatants derived from lactic acid bacteria (LAB) Lacticaseibacillus rhamnosus and Lacticaseibacillus paracasei UFTM 2.9. The use of LAB supernatants provided an eco-friendly and sustainable route for nanoparticle production, avoiding toxic reagents while exploiting biologically active metabolites for bioreduction and stabilization. The synthesized nanostructures were characterized by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX), scanning-transmission electron microscopy (STEM), ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) and zeta potential analysis. In vitro assays using Vero-CCL81 cells demonstrated that the nanostructures exhibited low cytotoxicity, confirming their potential biocompatibility. Antibacterial and antibiofilm activities were evaluated against Escherichia coli ATCC 25922, revealing significant inhibitory effects. These findings highlight a novel and sustainable route for producing niobium oxide nanostructures via LAB-mediated synthesis, with promising implications for biomedical and food safety applications.
DNA nanostructures are promising drug delivery platforms but often suffer from limited structural stability and high production complexity. Cisplatin can cross-link DNA and act as a therapeutic agent, offering a simplified approach to stabilize DNA nanostructures while incorporating therapeutic functionality. Here, we explore cisplatin-mediated compaction of a single-stranded DNA scaffold to form stable nanoparticles and evaluate their potential as radiosensitizers. Cisplatin-induced cross-linking produced compact DNA nanoparticles with size and morphology controlled by mixing ratio and incubation time, reaching maximum loading near a 1:1 cisplatin-to-nucleotide mixing ratio, resulting in 0.28 ± 0.06 bound Pt atoms per nucleotide. The nanoparticles showed high thermal stability with the onset of thermal degradation between 80 and 90 °C and remained structurally stable at 4 °C storage for months. Clonogenic assays in FaDu cells demonstrated radiosensitization, with a dose enhancement ratio of 1.17 ± 0.07 at 10% survival. Cisplatin-mediated cross-linking provides a simple and effective method for producing stable DNA nanoparticles without complex origami assembly. The resulting structures retain the radiosensitizing properties of platinum while offering improved stability and storage characteristics. These platinated DNA nanoparticles represent a promising platform for further development of scalable DNA-based radiosensitizers with high drug loading, monodispersity, stability, and versatility for further functionalization.
Herein, we investigate how aliovalent doping and application of an external electrical field modulates the catalytic activity of nanoscale ceria (nCeO2) towards CO oxidation. Gd3+ and La3+ were doped into the nCeO2 lattice. Such doping influences the concentration and mobility of oxygen vacancies, which are promoting CO oxidation to CO2. When applying an electric potential, charge transport within nCeO2 is modulated. Our results show that both dopants Gd3+ and La3+ lead to an increasing VO concentration, whereas the impact of the applied potential on the oxidation behaviour varies with catalyst composition. The applied electric potential markedly improves the activity of undoped nCeO2 and 5% Gd3+-doped nCeO2; however, it causes no significant change in CO oxidation capability in 2.5% Gd3+-doped and La3+-doped samples. These findings can be understood considering the applied potential and its influence on the polaron mobility and VO arrangement, which are controlled by the underlying oxidic defect structure.
Achieving rapid and flexible control of friction across different material surfaces is of great significance and remains a longstanding challenging goal in modern tribology. Here, we demonstrate dynamic structural superlubricity in monolayer MoS2-coated gold surfaces induced by external mechanical actuation. By tuning the excitation frequency to the cantilever resonance, stick-slip motion is effectively suppressed, leading to a significant reduction in friction even under high-load conditions. Experimental results, supported by a modified phononic friction model, reveal that torsional vibrations reduce energy barriers and promote transitions between atomic sites. This strategy provides a universal and reversible approach for active friction control at the nanoscale.
Second-generation tyrosine kinase inhibitors (TKIs) - bosutinib, nilotinib, and dasatinib - demonstrate therapeutic efficacy across various chronic malignancies, including chronic myelogenous leukaemia, acute lymphoblastic leukaemia, breast cancer, lung cancer, pancreatic cancer, and hepatocellular cancer. However, in the Biopharmaceutics Classification System, they are classified as class-II and class-IV drugs, exhibiting poor, pH-dependent solubility and low permeability, leading to poor and unpredictable bioavailability and variable plasma concentrations, compromising their clinical efficacy. Even though the oral route is the most widely accepted mode of administration, systematic analysis of the formulation database revealed that the conventional formulations encounter biopharmaceutical barriers limiting the therapeutic performance of drugs. Hence, this review examines nanotechnology-driven solutions that may improve the second-generation TKIs' biopharmaceutical properties for better therapeutic performance by enhancing their pharmacokinetic properties. Various nanosystems, such as solid lipid nanoparticles, nanostructured lipid carriers, polymeric micelles, polymeric nanoparticles, nanocrystals, self-nanoemulsifying drug delivery systems, and nanosuspensions, have been developed to enhance solubility, permeability, and bioavailability. The nanoformulations achieved variable improvements in solubility and bioavailability (1.5- to 38-fold) compared with free drugs, depending on surface characteristics, carrier composition, and drug properties. This was possible through tailored particle size, drug loading, and precise drug release kinetics via various mechanisms. This review consolidates the evidence from peer researchers on positioning nanoformulations as a transformative tool to improve the efficacy of second-generation TKIs. Critical evaluation was performed based on solubility/permeability enhancement potential, safety profile, toxicological burden, long-term stability, scalability, and feasibility for clinical transition.
Nanoglasses are a class of non-crystalline materials composed of nanoscale glass regions separated by glass-glass interfaces that possess distinct structural and thermodynamic characteristics. These internal interface regions with finite width of the order of several nanometres introduce excess free volume, altered short- and medium-range order, including the distribution of chemical constituents, and modified energetic states compared with conventional homogeneous glasses, giving rise to unique structural and functional properties. Additionally, the interfaces between the glass cores and the glass-glass interfaces need to be considered, as the specific interface areas are large. In this perspective paper, we discuss the structure, thermodynamics, and stability of glass-glass interfaces and examine their implications for the design and properties of nanoglasses, highlighting that this approach represents a novel pathway for modifying amorphous materials more broadly. Particular attention is given to columnar thin-film nanoglasses, where vertically aligned glassy columns create a high density of internal interfaces. We outline how interfacial excess energy, configurational entropy, and relaxation processes influence the metastability and properties of these materials. Furthermore, we discuss perspectives on how the control of interface density and chemistry may enable tailoring of mechanical, diffusion, and functional properties, including enhanced plasticity, altered transport behaviour, and tuneable optical or electronic responses. Finally, open questions regarding interfacial structure, thermodynamic driving forces, and stability are identified, emphasizing opportunities for integrating nanoglasses into advanced functional thin-film systems.
The incorporation of copper and oxygen into zinc telluride (ZnTe) thin films deposited by radio-frequency magnetron sputtering from a single ZnTe–CuO composite target was investigated. The nominal Cu and O concentrations ranged from 3 to 13 atom %, and films were grown at substrate temperatures of 300 and 350 °C. Energy-dispersive X-ray spectroscopy confirmed controlled compositional transfer from the target to the films. X-ray diffraction analysis revealed that all films are polycrystalline, exhibiting a coexistence of zinc blende and wurtzite ZnTe phases. Low dopant concentrations produced only minor lattice modifications, while higher Cu and O contents promoted the formation of Cu 2− x Te secondary phases, as confirmed by Raman spectroscopy, grazing-incidence X-ray diffraction and scanning electron microscopy. Optical measurements showed a significant reduction in infrared transmittance with increasing Cu concentration, attributed to the metallic-like absorption of Cu 2− x Te phases. Electrical characterization revealed a transition from semiconducting to highly conductive behavior with resistivity decreasing from approximately 10 2 to 10 −2 Ω·cm for films grown at 300 °C and from 10 1 to 10 −3 Ω·cm for films grown at 350 °C. Simultaneously, the carrier concentration increased from approximately 10 17 to 10 21 cm −3 and the mobility from 10 −1 to 10 1 cm 2 ·V −1 ·s −1 . These results indicate that structural, optical, and electrical properties of ZnTe are primarily influenced by Cu incorporation and the formation of conductive Cu-rich secondary phases, yielding a biphasic system composed of semiconducting ZnTe and conductive Cu-rich telluride phases. These material properties suggest potential relevance for future studies of back-contact materials in CdTe-based solar cells.
Multidrug resistance (MDR) remains a major barrier to successful cancer chemotherapy, frequently resulting in therapeutic failure, tumor relapses, and poor clinical outcomes. Among the diverse mechanisms underlying MDR, the overexpression of ATP-binding cassette (ABC) transporters, particularly P-glycoprotein (P-gp, encoded by ABCB1) is one of the most extensively studied as it actively effluxes structurally diverse chemotherapeutic agents and reduces intracellular drug exposure below cytotoxic thresholds. In this review, we critically examine recent nanocarrier-based strategies developed to overcome P-gp-mediated resistance across major malignancies, including breast, lung, colorectal, gastric, and prostate cancers. These approaches are categorized according to their principal mechanisms of action: (i) direct functional inhibition of P-gp ATPase activity using small-molecule modulators such as quercetin, ᴅ-α-tocopheryl polyethylene glycol succinate, and tariquidar, (ii) circumvention of membrane efflux through receptor-mediated endocytosis, intracellular trafficking control, or tumor-responsive drug release, and (iii) suppression of transporter expression via co-delivery of siRNA, shRNA, or anti-miRNA payloads targeting ABCB1 regulatory pathways. We further discuss advances in nanoplatform engineering, including lipid-based nanoparticles, polymeric micelles, lipid–polymer hybrid systems, and biomimetic carriers designed to enhance tumor selectivity and intracellular retention. Preclinical evidence consistently demonstrates improved drug accumulation, restored chemosensitivity, and reduced systemic toxicity. Nevertheless, clinical translation remains constrained by tumor heterogeneity, variable biological barriers, large-scale manufacturing requirements, and regulatory complexity. Overall, nanoparticle-mediated modulation of P-gp represents a promising strategy toward precision oncology, although future success will depend on scalable design, mechanistic standardization, and biomarker-guided clinical implementation.
Poly(ε-caprolactone) nanocapsules containing breu branco ( Protium heptaphyllum ) essential oil were successfully prepared by nanoprecipitation and optimized using a Box–Behnken design. Spherical nanosystems were obtained, with a mean particle size of 172.10 ± 0.90 nm, a polydispersity index of 0.14 ± 0.04, a zeta potential of −25.49 ± 1.08 mV and an encapsulation efficiency above 99%, in addition to long-term colloidal stability. Cell viability assays in HaCaT cells showed high biocompatibility, with cell viability above 70% up to 6 mg/mL and only moderate toxicity at 12 mg/mL. In antimicrobial assays, the free oil had no inhibitory effect against Staphylococcus aureus , while the nanocapsules exhibited a minimum inhibitory concentration of 0.55 mg/mL, indicating enhanced antibacterial activity. Wound-healing assays further demonstrated improved keratinocyte migration compared to serum-free controls. Additionally, cytokine profiling by cytometric bead array indicated an anti-inflammatory profile, with strong suppression of IL-6 and selective increases in IL-2, IL-4, and TNF-α at higher doses (6 mg/mL) in nanocapsule-treated fibroblasts. Overall, these findings demonstrate that nanoencapsulation not only stabilizes breu branco essential oil but also enhances its antimicrobial, regenerative, and immunomodulatory effects, while fostering the sustainable valorization of Amazonian biodiversity.
Plasma-facing components (PFCs) in fusion reactors are exposed to extreme radiation and thermal environments, leading to material degradation processes such as sputtering erosion and amorphization. This study investigates and compares the erosion behaviour of tungsten (W) in potential ceramic-based PFC materials, specifically tungsten carbide (WC) thin films and their nanocomposite counterpart, WC–WO3, under 100 keV Kr+ ion irradiation. The films were irradiated at fluences of 1 × 1016, 3 × 1016, and 1 × 1017 ions/cm2. Rutherford backscattering spectrometry was employed to evaluate W sputtering yields and compositional stability. The WC–WO3 nanocomposite exhibited significantly reduced W erosion compared to pure WC films, attributed to the higher W binding energy and the existence of heterointerfaces within the nanocomposite matrix. SRIM simulations corroborated the experimental sputtering trends. Furthermore, preferential sputtering of lower-Z elements (C and O) was observed in both material systems. Glancing incidence X-ray diffraction analysis revealed post-irradiation grain growth in WC–WO3 films, while scanning electron microscopy results show morphological changes, indicating dynamic microstructural evolution rather than amorphization under irradiation. These results highlight the potential of WC–WO3 nanocomposites as erosion-resistant and structurally resilient candidates for future plasma-facing applications in fusion reactors.
Accurate detection of ions in aqueous environments, ranging from trace to high concentrations, is essential for monitoring natural water resources, treatment facilities, and wastewater systems. Solid-state sensors have emerged as versatile platforms for this purpose due to their adaptability in geometry, compatibility with electronic integration, portability, and low energy requirements. A wide variety of active materials have been investigated, including metal oxides, graphene, carbon nanotubes, silicon nanowires, AlGaN/GaN, MXenes, transition metal dichalcogenides, and organic polymers all of which can be tailored for sensor development. Sensor selectivity and functionality can be enhanced through strategies such as defect engineering, nanoparticle doping, surface functionalization with organic molecules, or incorporation of advanced recognition elements like metal–organic frameworks, covalent organic frameworks, ion-imprinted polymers, and biomaterials. Hybrid nanocomposites and ion-selective membranes further expand the design space, enabling customized performance for specific applications. This review systematically examines the materials employed in solid-state ion sensors, their transduction mechanisms, and analyte interactions with sensing media, while critically evaluating advantages, limitations, fabrication approaches, and performance metrics. In addition, recent advances in sensor arrays are highlighted to demonstrate progress toward multiplexed detection. By consolidating these developments, this work provides a comprehensive framework to guide the rational selection of active and sensing materials for designing electrochemical and electrical devices capable of reliable, real-time ion monitoring in water.
Atomic force microscopy (AFM) relies strongly on tip geometry and mechanical integrity for stable and reproducible surface measurements. Here, we present an exploratory study of tungsten–carbon (W–C) AFM tips with complex three-dimensional (3D) architectures fabricated by helium ion beam-induced deposition (He+ FIBID) directly onto commercial AFM cantilevers bearing a pre-existing tip. Hollow nanopillars, nanohelices, and nanospirals were tested on a calibrated reference sample with a nominal step height of 20 nm using two AFM instruments under comparable operating conditions. Under the conditions explored here, selected 3D-printed tips reproduced the nominal step height of the calibration structure, yielding values consistent with those obtained using commercial probes on the same sample. To relate probe operation to structural outcome, each tip was examined by electron microscopy before and after AFM use. The main degradation modes were geometric deformation of the apex or shaft and mechanical fracture, most frequently at the tip–cantilever interface. While a few structures remained operational through repeated measurement cycles, others failed during the initial approach or early scanning stages, highlighting current limitations in robustness and reproducibility. These results show that complex He+ FIBID-grown nanoarchitectures can operate as AFM probes under basic test conditions, while also making clear that substantial optimization is still required.
HIV pre-exposure prophylaxis (PrEP) encompasses antiviral drugs or formulations that aim to prevent the establishment of a permanent infection if exposure occurs. Conventional oral PrEP approaches require a daily drug regimen for effective prophylaxis, which can become burdensome, and pill fatigue creates challenges for adherence. There is, consequently, interest in the development of long-acting formulations of antiretrovirals that provide protection over extended periods of time after a single treatment. Nanoformulations and nanoparticle delivery strategies play an important role in achieving long acting (LA)-PrEP. This manuscript reviews emerging nanoparticle delivery platforms for LA-PrEP with a particular focus on four distinct classes of nanomaterials, namely, polymeric nanoparticles, lipid-based nanoparticles, inorganic nanoparticles, and hybrid nanoparticles. Nanoparticle design considerations and targeting strategies for the individual classes are examined, and the opportunities and challenges for the different nanomaterials approaches in the context of LA-PrEP are discussed.
This study reports the design and synthesis of a C3-symmetric discotic tetrathiafulvalene (TTF) derivative, MeS-TTF-Ts, as a molecular platform for the self-assembly of one-dimensional conductive nanostructures. The molecular architecture contains three TTF units radially arranged around a rigid C3-symmetric core, enabling the formation of highly ordered one-dimensional assemblies through cooperative π–π stacking and directional intermolecular interactions. Solution casting of MeS-TTF-Ts produced nanorod and nanofiber structures with morphologies strongly dependent on the solvent conditions. AFM and SEM observations revealed that distinct supramolecular structures were formed depending on the solvent and substrate used, suggesting that molecular interactions and assembly processes play important roles in determining the resulting morphologies. Furthermore, MeS-TTF-Ts was combined with the strong electron acceptor F4TCNQ to form a charge-transfer complex, (MeS-TTF-Ts)(F4TCNQ)3, which yielded well-defined one-dimensional nanofibers. UV–vis and FTIR spectroscopic analyses confirmed substantial charge transfer from MeS-TTF-Ts to F4TCNQ through the formation of F4TCNQ− and TTF+ species. These results indicate the formation of a highly charge-transferred donor–acceptor assembly in the nanofibers. Electrical conductivity measurements revealed that the (MeS-TTF-Ts)(F4TCNQ)3 nanofibers exhibit a conductivity of 1.24 × 10−2 S·cm−1. These findings demonstrate that rational molecular design combined with controlled supramolecular self-assembly provides an effective strategy for constructing one-dimensional conductive nanostructures based on organic charge-transfer systems.
The homogeneous–heterogeneous catalysis gap remains an unresolved challenge in solar fuels research. Molecular catalysts offer unique selectivity and mechanistic transparency but suffer from poor electrode contact and limited recyclability, while heterogeneous semiconductors provide scalable light harvesting but lack precisely defined active sites. Anchoring molecular ruthenium (Ru) catalysts onto heterogeneous semiconductors, like carbon nitride (C 3 N 4 ), offers a chemically rational strategy to bridge this gap, yielding hybrid photoelectrodes capable of driving ammonia oxidation, a reaction of growing importance as a sustainable hydrogen carrier. Inspired by natural photosynthesis, in which a light-harvesting antenna is spatially coupled to a multielectron catalytic centre, the proposed hybrid system assigns distinct and complementary roles to each component: C 3 N 4 absorbs visible light, separates charge carriers, and provides a structurally tunable aromatic surface, while the metal complexes, e.g., RuBda, RuTda, or RuTpyBpy, accept photogenerated holes and drive the demanding six-electron oxidation of ammonia through well-defined coordination chemistry. Two anchoring strategies, covalent amide bond formation exploiting the surface amine groups of C 3 N 4 , and non-covalent π–π and C–H···π interactions mediated by pyrene-functionalized ligands, are presented as complementary rather than competing routes to the heterointerface, each controlling surface density, electronic coupling, and catalyst stability differently. This perspective article examines how the structural diversity of the C 3 N 4 allotropes, spanning semicrystalline polymeric C 3 N 4 , highly ordered poly(heptazine imide), and high-surface-area amorphous sulfur-doped C 3 N 4 , offers a tunable platform for optimizing charge carrier dynamics at the hybrid interface. Finally, photoelectrocatalysis is the enabling configuration: Simultaneous illumination and electrochemical bias reduce the thermodynamic penalty, suppress charge recombination, and provide independent control over product selectivity. Despite available materials, precedent reactions, and compelling mechanistic rationale, no study to date has reported photoelectrocatalytic ammonia oxidation at a C 3 N 4 –Ru hybrid photoelectrode, this gap is the motivation and the central argument of this perspective.
The H2 evolution from water electrolysis can be coupled with co-generation of other added-value products through biomass oxidation. In this study, we investigate the photoelectrochemical oxidation of glycerol using visible-light-responsive carbon nitride /bismuth vanadate (CN/BiVO4) heterojunction photoelectrocatalysts. Different CN materials were explored, including polymeric carbon nitride (PCN), crystalline poly(heptazine imides) (PHI-Cat, in which Cat = Na, K, or Cs), and poly(triazine imide) (PTI-Li). The CN materials were spin-coated onto fluorine-doped tin oxide (FTO) substrates, followed by the Bi electrodeposition step and conversion to BiVO4 in the presence of vanadyl acetylacetonate at 500 °C for 2 h. The CN/BiVO4 heterojunctions presented bandgap energy values, Eg, similar to pure BiVO4. X-ray diffraction analysis also revealed that the BiVO4 phase was not altered by the presence of the CN. However, scanning electron microscopy analysis coupled to energy-dispersive X-ray spectroscopy (SEM-EDS) revealed regions rich in Bi and V, and others rich in C and N, suggesting the formation of heterojunctions. Photoelectrochemical studies demonstrated that BiVO4 is active for both water and glycerol (1.0 mol·L−1) oxidation, with a fourfold increase in photocurrent at 1.23 V vs reversible hydrogen electrode (RHE) upon glycerol addition. Clearly, the type of nitride employed in the heterojunctions influences the activity of the material for glycerol oxidation, with the photocurrent at 1.23 V vs RHE following the order: PCN/BiVO4 > BiVO4 ≈ PHI-Cs/BiVO4 > PHI-K/BiVO4 ≈ PHI-Na/BiVO4 > PTI(Li)/BiVO4. The SEM-EDS analysis after electrochemical tests revealed that the presence of crystalline CNs induces the segregation of vanadium oxides, contributing to a decrease in activity. On the other hand, the superior performance of PCN/BiVO4 is attributed to a greater thermal stability of PCN during BiVO4 synthesis, as indicated by thermogravimetric analysis. These findings highlight the dual importance of electronic compatibility and thermal resilience of CN materials in designing efficient heterojunction photoanodes for biomass-assisted hydrogen production.
