Search Results (1,577)

The drug-encapsulated hybrid hydrogels possessed several expected properties, including porous microstructure, conductivity, adhesive strength, antioxidant activity, antibacterial properties, and cytocompatibility, and have great potential in biomedical applications, such as skin wound hydrogel dressings and bio-adhesives. In this paper, the quercetin-loaded hybrid hydrogels (SSA-QRs) were fabricated using silk fibroin (SF), alginate, and silver-doped reduced graphene oxide (Ag@rGO) nanosheets, incorporating quercetin-encapsulated PF-127 (PF127-QR) micelles. Scanning electron microscopy (SEM) images confirmed that the fabricated hybrid hydrogels possessed an interconnected porous microstructure. The mechanical properties of hydrogels could be regulated by adjusting the content of incorporated Ag@rGO nanosheets and PF127-QR micelles. Furthermore, the obtained SSA-QR hydrogels displayed the expected swelling properties, and the swelling rates could reach 1200–1700% in 120 min, in the equilibrium state. The fabricated SSA-QR hydrogels possessed apparent conductivity and self-healing ability. In addition, SSA-QR hydrogels exhibited strong adhesive performance on the surface of different materials, including skin, metal, wood, plastic, and glass. The typical antibacterial testing using Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) confirmed the excellent antibacterial activities of SSA-QR hydrogels. Moreover, SSA-QR hydrogels displayed good antioxidant ability and intracellular ROS scavenging ability. However, the increased content of Ag@rGO nanosheets could cause a great increase in the hemolysis ratio for SSA-QR hydrogels. Fluorescent images, cell counting kit-8 (CCK-8) assay, and cell scratch testing confirmed their excellent cytocompatibility and cell pro-migration ability. The available results demonstrated a facile strategy to prepare the quercetin-loaded hydrogel for applications of wound hydrogel dressing and bio-adhesives. Full article

Skin aging could lead to dermal collagen loss and elastic fiber degradation, ultimately manifesting as skin laxity. We aimed to counteract this by using poly-L-lactic acid (PLLA) microsphere (MS)-based fillers to facilitate long-term volume restoration through collagen regeneration. However, conventional MSs exhibit limitations such as broad size distribution and surface irregularities, which are frequently associated with significant adverse reactions. This study employed shirasu porous glass (SPG) membrane emulsification to fabricate uniform and well-shaped polyethylene glycol-block-poly (L-lactic acid) (PEG-PLLA) MSs. A single-factor experiment was employed to optimize the parameters. The optimal preparation conditions for PEG-PLLA MSs were as follows: PEG-PLLA concentration of 40 mg/mL, polyvinyl alcohol (PVA) concentration of 0.5%, and magnetic stirring speed of 200 rpm. Under the optimal conditions, the average particle size of PEG-PLLA MSs was 58.982 μm, and the span value (SPAN) was 1.367. In addition, a cytotoxicity assay was performed, and the results revealed no significant toxicity of the MSs toward L929 mouse fibroblasts at concentrations below 500 μg/mL. Furthermore, PEG-PLLA MSs significantly enhanced the production of key extracellular matrix (ECM) components—type I collagen (Col-I), type III collagen (Col-III), and hyaluronic acid (HA)—while simultaneously alleviating cellular oxidative stress responses. This work offers a reliable and reproducible fabrication strategy for developing biocompatible MS fillers with controllable particle sizes. Full article

Background: Root canal sealers may come into direct contact with periapical tissues, particularly in cases of apical extrusion, potentially influencing periapical healing and treatment outcomes. Cytotoxicity assessment represents a clinically relevant parameter when selecting endodontic sealers. However, evidence derived from in vitro studies remains heterogeneous and challenging to interpret from a clinical perspective. Therefore, the aim of this systematic review was to critically evaluate the in vitro cytotoxicity of all root canal sealers that have been commercially marketed over the years, excluding experimental materials, and to contextualize the findings in relation to clinically relevant experimental conditions. Methods: This systematic review was conducted according to PRISMA guidelines and preregistered on the Open Science Framework. PubMed, Scopus, and the Cochrane Library were searched up to 30 November 2025. In vitro studies evaluating the cytotoxicity of commercially available root canal sealers using validated cell viability or proliferation assays were included. Data extraction focused on sealer composition, setting condition, extraction protocols, exposure parameters, and cytotoxic outcomes. Due to marked methodological heterogeneity, a qualitative synthesis was performed. Results: Ninety-eight in vitro studies were included. All categories of root canal sealers demonstrated some degree of cytotoxicity, particularly when tested in freshly mixed conditions, at higher extract concentrations, or after prolonged exposure. Bioactive and calcium silicate-based sealers generally showed a more favorable cytotoxicity profile compared with conventional materials, especially after complete setting and at diluted concentrations, although cytotoxic effects were reported under specific experimental conditions. Resin-based sealers, including AH Plus, exhibited condition-dependent cytotoxicity, while zinc oxide–eugenol and glass ionomer sealers tended to display higher cytotoxic potential. Conclusions: In vitro cytotoxicity of root canal sealers varies according to material composition and experimental conditions. Bioactive sealers generally exhibit a more favorable biological profile, which may be clinically relevant in situations involving sealer extrusion or prolonged tissue contact. Standardized testing protocols and further translational studies are required to support evidence-based clinical material selection. Full article

Atomic Layer Deposition (ALD) is a key thin-film fabrication technique that enables the growth of ultra-thin, conformal, and compositionally controlled layers for applications in nanoelectronics, optoelectronics, and energy devices. However, the high cost and operational complexity of commercial ALD systems limit their accessibility in academic and emerging research environments. In this work, a low-cost, automated thermal ALD system is designed, assembled, and experimentally validated for the deposition of zinc oxide (ZnO) thin films. The developed system enables precise control of precursor dosing, purge sequences, and substrate temperature via an integrated LabVIEW–Arduino control architecture, allowing reproducible and stable thin-film growth. The design allows the use of various precursors through high-precision three-way diaphragm valves. In addition, the system allows continuous purge gas flow in the reaction chamber, which enhances the drag velocity of the precursor gas, reducing dosage requirement, accelerating chamber saturation time and lowering the total consumption of precursors per deposition cycle. ZnO thin films were successfully grown on silicon and glass substrates at 200 °C using diethylzinc (DEZ) as the metal precursor and hydrogen peroxide (H₂O₂) as the oxidant. The process exhibited self-limiting growth characteristics typical of ALD, yielding a growth per cycle of approximately 0.8 Å. The deposited ZnO films exhibited optical transparency of 70–80% in the visible region, a refractive index of approximately 1.9, and an optical bandgap close to 3.4 eV, which are consistent with values reported for high-quality ZnO films grown in commercial ALD systems. These results demonstrate that the proposed low-cost platform is capable of producing functional ZnO thin films with properties comparable to those obtained with conventional commercial reactors. Overall, this work presents an accessible and scalable thermal ALD system that significantly reduces equipment costs while maintaining reliable process control and film quality, offering a practical framework for expanding thin-film research capabilities across microelectronics, optoelectronics, and nanotechnology laboratories. Full article

Transition metal (TM)-doped zinc oxide (ZnO) and zirconium dioxide (ZrO₂) nanocrystals exhibit complex correlations between crystal structure, defect chemistry, vibrational properties, and magnetic behavior that are strongly governed by synthesis route and dopant incorporation mechanisms. This review critically summarizes recent progress on Fe-, Mn-, and Co-doped ZnO and ZrO₂ nanocrystals synthesized by wet chemical, hydrothermal, and microwave-assisted hydrothermal methods, with emphasis on synthesis-driven phase evolution and apparent solubility limits. ZnO and ZrO₂ are treated as complementary host lattices: ZnO is a semiconducting, piezoelectric oxide with narrow solubility limits for most 3d dopants, while ZrO₂ is a dielectric, polymorphic oxide in which transition metal doping may stabilize tetragonal or cubic phases. Structural and microstructural studies using X-ray diffraction, electron microscopy, Raman spectroscopy, and Mössbauer spectroscopy demonstrate that at low dopant concentrations, TM ions may be partially incorporated into the host lattice, giving rise to diluted or defect-mediated magnetic behavior. When solubility limits are exceeded, nanoscopic secondary oxide phases emerge, leading to superparamagnetic, ferrimagnetic, or spin-glass-like responses. Magnetic measurements, including DC magnetization and AC susceptibility, reveal a continuous evolution from paramagnetism in lightly doped samples to dynamic magnetic states characteristic of nanoscale magnetic entities. Vibrational spectroscopy highlights phonon confinement, surface optical phonons, and disorder-activated modes that sensitively reflect nanocrystal size, lattice strain, and defect populations, and often correlate with magnetic dynamics. Rather than classifying these materials as diluted magnetic semiconductors, this review adopts a synthesis-driven and correlation-based framework that links dopant incorporation, local structural disorder, vibrational fingerprints, and magnetic response. By emphasizing multi-technique characterization strategies required to distinguish intrinsic from extrinsic magnetic contributions, this review provides practical guidelines for interpreting magnetism in TM-doped oxide nanocrystals and outlines implications for applications in photocatalysis, sensing, biomedicine, and electromagnetic interference (EMI) shielding. Full article

Quaternary lavas (ankaramite, basalt, basaltic andesite, andesite, dacite) from the Kamchatka, Kurile, Ecuador and Cascade volcanic arcs contain Cl-bearing mineral microinclusions in rock-forming minerals and groundmass volcanic glass. They are represented by chlorargyrite (with a variable amount of native Ag), Cu, Ag, Sn, and Zn compounds with Cl and S, Sn- and Pb-Sb oxychlorides compositionally similar to abhurite and nadorite, as well as bismoclite and Cl-F-apatite. The Cl-bearing compounds with chalcophile metals are best approximated by mixtures of chlorargyrite with Cu sulfides, malachite, or azurite. Some Cl-bearing solid microinclusions in magmatic rock-forming minerals could have formed from Cl-rich melts exsolved from arc magmas during differentiation. Alternatively, specific magmatic microinclusions may record the decomposition of primary sulfides in the presence of Cl-bearing magmatic volatiles. Post-magmatic Cl microminerals found in fractures, pores, grain contacts, and groundmass glass are most probably precipitated from hydrothermal fluids accompanying their emplacement at the surface and post-eruption transformations in active fumarole fields. Assemblages of Cl-bearing microminerals with native metal, alloy, sulfide, oxide, and sulfate microinclusions in arc lavas potentially record late-magmatic to post-magmatic stages of formation of the epithermal and possibly porphyry mineralization beneath arc volcanoes. Full article

The present paper reports the preparation of a nanocomposite thin film consisting of calcium itaconate and graphene oxide (GO). The composite is a black powder consisting of individual shiny prismatic crystals at varying degrees of maturity. The crystal size distribution is quite narrow: from 3.6 to 6.2 μm in length and from 0.7 to 1.1 μm in width. Thin-film-based acetone sensor made of a nanocomposite was fabricated by spin coating of calcium itaconate–GO nanoparticles on glass plates. The thin-film acetone sensor was characterized using FTIR, XRD, SEM, TEM, and the low-temperature nitrogen sorption–desorption method. The sensor response time is 7.66 ± 0.07 s (s_r = 0.92%), and the relaxation time when blowing the surface with clean air or inert gas (nitrogen, argon) is 9.26 ± 0.12 s (s_r = 1.28%). The sensing mechanism of the sensor for detecting acetone at room temperature was also is proposed based on phenomenological understanding due to the absence of direct electronic/charge-transport evidence. Full article

In the last few years, Thin Film Transistors (TFTs) based on materials such as amorphous Indium–Gallium–Zinc Oxide (a-IGZO) have gained interest in large-area and low-cost electronics due to their high carrier mobility, high on/off current ratio, low off-state current, and steep subthreshold slope. These characteristics make IGZO TFTs suitable for radio-frequency identification (RFID) tags, analog-to-digital converters (ADCs), logic circuits, sensors, and analog components, including operational amplifiers (OPAMPs). This work presents the implementation and characterization of an OPAMP based on n-type a-IGZO TFTs fabricated on glass substrate. Two previously reported design strategies were integrated: a positive feedback network to increase the output impedance and a topology to enhance the transconductance of the driver transistors, both in the differential input stage. A gain of 26 dB, a bandwidth of 2.4 kHz, a gain–bandwidth product (GBWP) of 48 kHz, and a phase margin of 64° were obtained, which confirms the reliability of the design and the fabrication process. Full article

Two amide-preformed aromatic diamine monomers, N,N-bis(4-(3-aminobenzamido)phenyl)-N’,N’-bis(4-methoxyphenyl)-1,4-phenylenediamine (m-6) and N,N-bis(4-(4-aminobenzamido)phenyl)-N’,N’-bis(4-methoxyphenyl)-1,4-phenylenediamine (p-6), were synthesized and utilized to prepare two series of electroactive poly(amide-imide)s (PAIs) through a two-step polycondensation reaction with commercially available aromatic tetracarboxylic dianhydrides. The obtained polymers exhibited solubility in various polar organic solvents, and most of them could form transparent, flexible films via solution casting. Thermal analysis indicated glass transition temperatures (T_g) ranging from 250 °C to 277 °C, as measured by DSC, with no significant weight loss observed before 400 °C in TGA tests. Cyclic voltammograms (CV) of the polymer films on ITO-coated glass substrates revealed two reversible oxidation redox pairs between 0.67 and 1.04 V vs. Ag/AgCl in an electrolyte-containing acetonitrile solution. The PAI films showed stable redox activity with high optical contrast both in the visible and near-infrared regions, transitioning from colorless in the neutral state to green and blue in the oxidized states. Furthermore, the polymer films retained good electrochemical and electrochromic stability even after more than 100 cyclic switching operations. The PAIs displayed outstanding electrochromic performance, including high optical contrast (up to 95%), rapid response times (below 4.6 s for coloring and 5.7 s for bleaching), high coloration efficiency (up to 240 cm²/C), and low decay in optical contrast (less than 5% after 100 switching cycles for most PAIs). Full article

This work presents results on laser-induced fabrication of metal and oxide structures on glass substrates. The Laser-Induced Reverse Transfer (LIRT) technique is applied using Zn and Sn, sintered ZnO and SnO₂, and oxide composite targets. The processing is performed by nanosecond pulses of a Nd:YAG laser system operated at wavelength of 1064 nm. Detailed analyses of the deposited material morphology, composition and structure are presented, as the role of the processing conditions is revealed. It is found that at the applied conditions of using up to five laser pulses, the deposited material is composed of a nanostructured film covered in microsized nanoparticle clusters or droplets. The use of metal targets leads to formation of structures composed of metal and oxide phases. The adhesion test shows that part of the deposited material is stably adhered to the substrate surface. It is demonstrated that the deposited materials can be used as resistive gas sensors with sensitivity to NH₃, CO, ethanol, acetone and N₂O, at concentrations of 30 ppm. The ability of the method to deposit composite structures that consist of a mixture of both investigated oxides is also demonstrated. Full article

The development of effective bone substitutes remains a central goal in regenerative medicine. In this study, lithium-modified bioglass-ceramics based on the 47.5S5 silicate oxide system were synthesized using the sol–gel method, followed by calcination and axial pressing to form cylindrical samples. These materials were sintered at 700 and 800 °C and subsequently examined to evaluate their structural, mechanical, and biological performance. Structural and microstructural analyses confirmed the presence of crystalline phases such as combeite (Na₆Ca₃Si₆O₁₈), NaLiSiO₄, Li₂SiO₃, and calcium silicates, indicating the successful incorporation of lithium within the glass-ceramic network. The bioceramics exhibited improved densification, deformability, and compressive strength with increasing sintering temperature. In vitro degradation in simulated body fluid revealed a consistent increase in mass loss with higher lithium content, suggesting enhanced resorbability linked to lithium oxide. Antibacterial testing indicated moderate antimicrobial activity, with slightly better results observed at higher sintering temperatures. Cell viability assays further supported the materials cytocompatibility. Taken together, these findings suggest that lithium substitution contributes positively to both mechanical robustness and biological behaviour, positioning these ceramics as promising bioresorbable bone substitutes with controlled degradation, suitable for bone tissue engineering where durability, bioactivity, and antimicrobial function are required. Full article

This study aims to address a major challenge and find solutions for developing less expensive, lighter, and more efficient energy storage materials while remaining environmentally friendly. This work combines the study of the structural, morphological, and optical properties of epoxy nanocomposites containing ZnO and SnO₂ and highlights the influence of oxide filler content on their energy storage performance. To this end, epoxy nanocomposites filled with metal oxides (ZnO and SnO₂) prepared by extrusion, a simple, economical, and reliable industrial method, were studied and compared. The materials obtained are inexpensive, lightweight, and highly efficient, and can replace traditional glass-based systems in the energy sector. The results of XRD, SEM, and FTIR analyses show the absence of impurities, the stability of the structures in humid environments, and the homogeneity of the prepared films. They also indicate that the nature and charge content of the oxide integrated into the polymer matrix play a significant role in the properties of the nanocomposites. Optical measurements were used to determine the film thickness, the type of electronic transition, the band gap energy, and the Urbach energy. Based on the results obtained, the prepared nanocomposite films appear to be promising materials for energy-based optical applications. Full article

Erosion wear represents a significant issue in piping systems across energy and chemical industries, particularly in elbows. This study develops a prediction model for erosion wear based on tangential and normal impact energy for elbow tubes fabricated from zinc oxide-modified bidirectional E-glass fiber-reinforced epoxy resin composites (ZnO-BE-GFRP). Using a combined CFD-DEM approach, the wear characteristics under gas–solid two-phase flow conditions were systematically investigated. The model quantifies the contributions of tangential and normal impact energy to material removal through the specific energy for cutting wear (e_t) and the specific energy for deformation wear (e_n), with key parameters calibrated against experimental data from ZnO-BE-GFRP. This study shows that the increase in gas velocity significantly intensifies wear, and the wear area extends towards the middle of the elbow as the gas velocity increases. The 40–45° area of the elbow is a high-risk wear zone due to the concentration of particle kinetic energy and high-frequency collisions. The particle size distribution has a significant impact on wear: as the degree of particle dispersion increases, the wear on the elbow extrados decreases. Full article

The increasing impact of global warming is predominantly driven by the extensive use of fossil fuels, which release significant amounts of greenhouse gases into the atmosphere. This has led to a critical need for alternative, sustainable energy sources that can mitigate environmental impacts. Photovoltaic technology has emerged as a promising solution by harnessing renewable energy from the sun, providing a clean and inexhaustible power source. Perovskite solar cells (PSCs) are a class of hybrid organic–inorganic solar cells that have recently attracted significant scientific attention due to their low cost, relatively high efficiency, low–temperature processing routes, and longer carrier lifetimes. These characteristics make them a viable alternative to traditional fossil fuels, reducing the carbon footprint and contributing to the fight against global warming. In this study, the SCAPS–1D numerical simulator was used in the computational analysis of a PSC device with the configuration FTO/ETL/BaZr(S_0.6Se_0.4)₃/HTL/Ir. Different hole transport layer (HTL) and electron transport layer (ETL) material were proposed and tested. The HTL materials included copper (I) oxide (Cu₂O), 2,2′,7,7′–Tetrakis(N,N–di–p–methoxyphenylamine)9,9′–spirobifluorene (spiro–OMETAD), and poly(3–hexylthiophene) (P₃HT), while the ETLs included cadmium suphide (CdS), zinc oxide (ZnO), and [6,6]–phenyl–C₆₁–butyric acid methyl ester (PCBM). Finally, BaZr(S_0.6Se_0.4)₃ was proposed as an absorber, and a fluorine–doped tin oxide glass substrate (FTO) was proposed as an anode. The metal back contact used was iridium. Photovoltaic parameters such as short circuit density (I_sc), open circuit voltage (V_oc), fill factor (FF), and power conversion efficiency (PCE) were used to evaluate the performance of the device. The initial simulated primary device with the configuration FTO/CdS/BaZr(S_0.6Se_0.4)₃/spiro–OMETAD/Ir gave a PCE of 5.75%. Upon testing different HTL materials, the best HTL was found to be Cu₂O, and the PCE improved to 9.91%. Thereafter, different ETLs were also inserted and tested, and the best ETL was established to be ZnO, with a PCE of 10.10%. Ultimately an optimized device with a configuration of FTO/ZnO/BaZr(S_0.6Se_0.4)₃/Cu₂O/Ir was achieved. The other photovoltaic parameters for the optimized device were as follows: FF = 31.93%, J_sc = 14.51 mA cm⁻², and V_oc = 2.18 V. The results of this study will promote the use of environmentally benign BaZr(S_0.6Se_0.4)₃–based absorber materials in PSCs for improved performance and commercialization. Full article

The fabrication of undoped and aluminium-doped zinc oxide thin films on quartz glass substrates through the aqueous spray method is reported. The prepared aqueous precursor solutions containing Zn²⁺ and varying mole percentages (0, 2, 4, and 8%) of Al³⁺ complexes were spray-coated onto quartz glass substrates preheated at 180 °C. The as-sprayed films obtained were then heat-treated at 450 °C for 30 min in a furnace to produce the various thin films. The structural and optical properties of the resultant thin films were analysed using the X-ray diffractometer (XRD) and ultraviolet–visible (UV-Vis) spectrophotometer. The XRD results revealed that the fabricated thin films have a prominent peak correlating to the (002) Miller index, which is the preferred orientation of the zinc oxide hexagonal wurtzite phase. The fabricated thin films with a film thickness of approximately 189 nm absorb light in the visible region and have a transmittance of over 80% even after being doped with aluminium. The photocatalytic activities of the thin films were evaluated via visible light irradiation of an aqueous methyl orange solution, and the Al-doped ZnO thin films exhibited good photocatalytic activities, which resulted in an increase in the doping mole percentages of aluminium. Full article