Perovskite solar cells (PSCs) have emerged as a transformative photovoltaic technology, combining high power-conversion efficiencies with inexpensive, solution-based processing. However, their intrinsic instability and incomplete optical absorption currently hinder their widespread application. The integration of quantum dots (QDs) into PSCs has arisen as a promising strategy to address these limitations. By broadening the absorption spectrum, passivating defects, and facilitating charge transport, QDs can push single-junction PSC efficiencies to similar to 26% while improving long-term stability. This review surveys recent progress in QDPSCs systems, covering QDs synthesis and incorporation methods, device architectures, and optoelectronic enhancements. We discuss the multifaceted roles of QDs in defect passivation, moisture resistance, and interface engineering, and highlight concerns about scalability and lead toxicity. Finally, we outline future directions such as lead-free QDs, tandem cell designs, and scalable manufacturing to position QD-enhanced PSCs as next-generation photovoltaic candidates.
Bloch surface waves (BSWs) in periodic multilayer photonic crystals (PCs) were excited using a 635-nm laser for testosterone hormone detection employing the Kretschmann-Raether configuration. A 24-layer ZrO2-SiO2 PC served as the key dielectric sensing medium for the evanescent field interaction with testosterone molecules in blood plasma. Although SiO2 does not bind strongly to testosterone, it provides the necessary low-index component to achieve high contrast with ZrO2. The layer combinations are ideal for low optical loss in biosensing. A 20-mu L mixture of phosphate buffered saline, testosterone, and blood plasma with the testosterone concentrations of 0.5, 1, 10, 100, and 200 mM were poured over the PC surface. The acceptable viscosity of this mixture helps adhere the BSW-based sensor to the BK7 prism coupler surface used in the experiment. The results of polarized reflected transverse magnetic waves indicate strong dependence on the angular shift. The lowest concentration (of 0.5 mM) was detected at an angle of approximately 51.2 degrees, while the highest concentration (of 200 mM) was spotted at 51.7 degrees. For concentrations < 10 mM, the sensitivity of the studied BSW-based sensor was found to be nonlinear with the angular shift; higher concentrations, however, showed this feature to be linear.
The effect of seed layer thickness on the optical and electrical properties of ZnO nanorods (NRs) for fast-response UV photodetector applications was investigated. Vertically aligned ZnO NRs were grown via a hydrothermal method using seed layers with various thicknesses ranging from 350 nm to 550 nm. FESEM characterization revealed that the synthesized ZnO NRs had average diameters of 71 - 175 nm and lengths of 1.3 - 2 mu m. UV-Vis spectra indicated that the sample with the thinnest seed layer (350 nm), which exhibited a higher aspect ratio, showed enhanced absorption in the UV region. p-n heterojunction photodetectors (PDs) based on the synthesized ZnO NRs were fabricated, and their I-V and I-t characteristics were evaluated. The results demonstrated that optimizing the seed layer thickness in accordance with the UV wavelength significantly improves the photodetector's responsivity, sensitivity, and quantum efficiency, while also achieving remarkably fast response and recovery times. These findings highlight the critical role of structural tuning in enabling high-performance, fast-response UV photodetectors.
Nano herbal therapeutics combine nanotechnology with herbal medicine to overcome challenges like poor bioavailability and instability of phytochemicals. These formulations enhance efficacy, safety, and patient compliance compared to conventional herbal and synthetic nanoparticle systems. Plant-derived nanoparticles (PDNPs) offer benefits including improved cellular uptake, low toxicity, eco-friendliness, and costeffectiveness. Several nano-formulated herbal compounds have shown promising outcomes in preclinical and clinical studies, especially in cancer, inflammation, and metabolic disorders. This review highlights the pharmacokinetics, pharmacology, and therapeutic potential of nano-herbal systems while comparing PDNPs to synthetic counterparts. We also explore their mechanisms of action, molecular signaling pathways, and roles in targeted delivery. Additionally, the review addresses challenges such as formulation stability, large-scale production, regulatory gaps, and long-term toxicity. A systematic literature review was conducted using databases like PubMed, Scopus, and Web of Science. Emerging tools such as AI-assisted formulation and biodegradable carriers are discussed as future directions. The integration of nanotechnology and herbal medicine presents a transformative approach to disease treatment. However, regulatory standardization, environmental safety, and ethical commercialization remain critical for clinical translation.
Antibacterial polymeric nanofibers derived from PAN nanofibers exhibit remarkable promise for a variety of applications in the biomedical field. In this study, we explored the incorporation of zinc oxide and copper oxide nanoparticles into PAN/ZnO/CuO nanofibers, which were meticulously fabricated using the electrospinning technique complemented by an ex-situ generation method. The structural properties of the PAN/ZnO/CuO nanofibers were characterized through XRD analysis, which confirmed a significant interaction between the ZnO/CuO nanoparticles and the electrospun PAN matrix. Additionally, FE-SEM and AFM imaging provided compelling visual evidence that the ZnO/CuO nanoparticles are uniformly distributed throughout the PAN nanofiber network, indicating a well-integrated composite structure. To evaluate their potential for clinical use, we rigorously tested the antibacterial efficacy of the PAN/ZnO/CuO nanofibers against a range of bacterial strains commonly found in hospital environments. The results were promising, revealing that these composite nanofibers exhibit a pronounced antibacterial effect against several pathogens, including Salmonella, Shigella, Escherichia coli, Streptococcus pneumoniae, and Staphylococcus aureus. Such findings suggest that these advanced nanofibers could play a crucial role in enhancing infection control measures in medical settings.
In this paper, we have used the Tight Binding model for the triangular graphene nanostructure, and by calculating the eigenenergy at the zigzag and armchair edges, and compared with graphene lattice energy spectra, we were able to predict the energy gap in this structure. By applying the Tight Binding Hamiltonian matrices for the unit cell and the first neighbors in the graphene lattice, we obtain the energy eigenvalues. We changed the problem conditions for the edges and observed that the zigzag edge has an electronic band with a zero-gap similar to a complete graphene lattice. But, the presence of the armchair edge has caused the formation of an energy gap. Eventually, we compared the results with experimental examples. The presence of an energy gap in the triangular nanostructure of graphene can be related to the edge of the armchair. Furthermore, the presence of active radicals and functional groups on the edge of the armchair reduces the energy gap in the nanostructure, which gives semiconductor properties to this structure.
Exploring semiconducting materials for applications in the spintronic devices we investigate structural, electronic and magnetic properties of (Sm, Co) Co-doped ZnS diluted magnetic semiconductor (Zn30Sm1Co1S32) by first principle calculations using GGA+U approximation. The total energy calculations depict the ferromagnetic state as the stable state in the Co-doped system with larger Sm-Co separation while for smaller Sm-Co separation the system shows antiferromagnetic character. The total density of states (DOS) calculations demonstrates semiconducting and metallic character in the spin up and spin down states respectively which discloses p-d hybridization between Co-d and S-p ion revealing half metallic behaviour with 100% spin polarization. These findings establish Zn30Sm1Co1S32 as promising material for spintronic applications, combining semiconductor functionality with magnetic ordering and spin polarization essential for next-generation electronic devices
Zinc oxide is a semiconductor material with an interesting potential for photocatalysis of organic pollutants. It has been prepared according an eco-friendly green method, using five various plant extracts (banana, rosemary, bitter orange, olive tree, comfrey). Two different synthesis processes were tested: a hotplate synthesis and a hydrothermal method. Metal precursor used was zinc acetate. Plants present in the process allowed the formation and the self-assembling of ZnO during the crystal growth thanks to the large chemical family of polyphenol which act as reductants. Crystalline and organic matter-free compounds obtained after annealing were characterized with diffractive reflectance spectroscopy (DRS) to determine gap energies and confirm ZnO belonging to semiconductors, X-ray diffraction to verify the crystalline structure and its features, Fourier transform infrared spectroscopy (FTIR) to check the characteristic functional group and scanning electron microscopy (SEM) to reveal the self-assembling forms of ZnO. Data about the shapes, dimensions and crystal planes of zinc oxide were regarded in the light of the plant and the synthesis method used. This work has highlighted the morphologies of ZnO obtained on the basis of the synthesis method and the plant extracts.
In this study, Ag-doped ZnWO4 fibers were successfully fabricated using a simple, low-cost drawing technique, and their structural, morphological, and optical properties were systematically investigated, with particular emphasis on their response to ionizing radiation. ZnWO4 and ZnWO4:Ag nanopowders were first synthesized via a coprecipitation method and subsequently embedded into a polymeric matrix to form flexible microfibers. X-ray diffraction (XRD) analysis confirmed the formation of a single-phase monoclinic wolframite ZnWO4 structure, while Ag incorporation induced slight peak shifting and reduced crystallinity due to lattice distortion. Raman spectroscopy further verified the preservation of characteristic WO2- vibrational modes. FESEM observations revealed the successful formation of continuous microfibers with average diameters of approximately 12 mu m for pristine ZnWO4 fibers and 15 mu m for Ag-doped fibers, with uniformly distributed Ag nanoparticles decorating the fiber surface, as confirmed by EDS and elemental mapping analyses. Optical studies demonstrated a strong emission band centered at similar to 500 nm in both photoluminescence (PL) and ion beam induced luminescence (IBIL) spectra. Notably, Ag-doped ZnWO4 fibers exhibited significantly enhanced luminescence intensity compared to undoped samples under both UV excitation and 2.2 MeV proton irradiation, attributed to Ag-induced defect states, improved charge carrier trapping, and enhanced radiative recombination. The IBIL intensity was substantially higher than PL due to the higher excitation efficiency of energetic protons. These findings highlight the strong potential of Ag-doped ZnWO4 nanofibers as advanced functional materials for ionizing radiation detection, scintillation devices, and smart textile applications.
Progressive evolution of nanostructured coatings with costume-made structural and optical properties is of major interest for different high-tech applications. This work targeted the incorporation of titanium dioxide (TiO2) nanoparticles to poly(methyl methacrylate) (PMMA) nanocomposite films across three concentrations (1%, 2%, and 3%) using the casting method. These films were later treated with cold dielectric barrier discharge (DBD) plasma to refine their structure and optical properties. Investigations were systematically studied through the work including the extinction coefficient, absorption coefficient, dielectric constant (real and imaginary), energy gap, Urbach energy, and refractive index. A significant increase resulted in the real dielectric constant, refractive index, and absorption coefficient, on the other hand, a decrease due to strong absorption was noted in the imaginary dielectric constant and extinction factor. Direct and indirect energy gap ranged from 4.7 to 4.5 eV, and 3.4 to 3.25 eV, respectively. Urbach energy data elevated from 366 to 395 meV, which suggests improved charge carrier transport attributed to structural modifications achieved by plasma induction. Also, cold DBD plasma treatment efficiently increased the roughness of the surface, and as a result, improved the film's optical absorption abilities. These findings were confirmed using structural analysis, X-ray diffraction (XRD) showed a mixture of semi-crystalline and amorphous phases. SEM examined revealed a uniform TiO2 distribution across the PMMA accompanied by gaining a roughened morphology. AFM analysis also showed a boost in surface roughness from 0.828 to 3.04 nm after incorporating TiO2 and applying plasma treatment. These results propose that PMMA/TiO2 nanocomposite films showed encouraging potential for applications in fiber optics, optical sensors, photocatalysis, and light-emitting diodes (LEDs).
Edwardsiella tarda infection can cause significant economic losses to the aquaculture industry. It causes haemorrhagic septicaemia in freshwater and marine fish, and serious health issues in humans and other animals. The abuse of antibiotics in aquaculture has been linked to the emergence of multidrug-resistant bacteria, and silver nanoparticles (AgNPs) are regarded as a potential therapeutic alternative. This study biosynthesised AgNPs using the methanolic leaf extract of Sonneratia caseolaris. A 0.1 mg/ml (H2) extract solution formed AgNPs successfully as indicated by brownish colour change after 24 h incubation and evidenced by UV-Vis spectroscopy. Energy-dispersive X-ray spectroscopy (EDS) revealed silver as the main constituent (84.49%). Transmission electron microscopy (TEM) displayed polydisperse, near-spherical nanoparticles with an average size of 22.3 nm. Fourier transform infrared (FTIR) analysis suggested that several functional groups were involved in SC-AgNPs formation. SC-AgNPs exhibited strong antibacterial activity against 12 E. tarda isolates from diseased African catfish and Asian swamp eels, including a beta-haemolytic strain (ET10). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined to be 2.5 mu g/mL. This study suggests that SC-AgNPs has the potential as an alternative to antibiotics to reduce the risk of antibioticresistance in aquaculture.
In this work, the fabrication and optical characterization of flexible hybrid plasmonic-excitonic films were made, which included a PDMS substrate covered by a dispersed Ag layer and a fluorescein/PVP top layer. The coupling of localized surface plasmon modes (SPPs) in the Ag layer with the excitonic transition of fluorescein molecules resulted in a strong enhancement of the fluorescence emission intensity. This effect is largely attributed to the good overlap of the spectral response of the silver plasmon, around 420 nm, with the fluorescein absorption band around 490 nm, providing the necessary conditions for an effective plasmon-exciton interaction. In addition, the laser-induced fluorescence (LIF) spectrum for an excitation wavelength of 532 nm evidenced the presence of a strong emission peak around 530 nm, whose intensity linearly depends on the excitation irradiance, indicating that the stability of the coupling process is guaranteed with in the system Hybrid architectures based on the PDMS/Ag/fluorescein-PVP guarantee brilliant future prospects regarding their implementation in biosensing and nanophotonic systems due to their flexibility, low cost, and scalability.
This study formulated and characterized metformin-loaded chitosan nanoparticles (NPs) using the ionic gelation technique and evaluated their drug release kinetics. Characterization confirmed successful drug encapsulation, with FTIR indicating compatibility, XRD showing reduced crystallinity, and particle sizes ranging from 184.28 to 246.82 nm. The NPs exhibited stable zeta potentials (+42.38 to +49.06 mV) and high entrapment efficiencies (68.42% - 81.26%). In vitro drug release studies at pH 7.4 and pH 2 demonstrated an initial burst release, followed by sustained release over 24 hours. The cumulative drug release ranged from 81.92% to 97.72% at pH 7.4 and 89.4% to 98.1% at pH 2, with a faster release at pH 2. Drug release kinetics followed First-order for MN1, while MN2 and MN3 best fitted the Higuchi model, indicating diffusion-controlled release through the chitosan polymeric network. These findings highlight the potential of metformin-loaded chitosan NPs for sustained drug delivery, which may enhance patient compliance by reducing dosing frequency. Future studies should further explore their clinical applications.
In this study, the structure of zinc oxide doped with nickel at different concentrations of 0%, 1%, 3%, 5%, and 10% was examined. Zinc oxide was synthesized using the sol-gel method. Prepared sols coated on silicon wafer by spin coating method to be used as a photodiode in an electrical circuit for evaluation. XRD, UV-Vis, FT-IR, and SEM analyses were utilized to compare the structures of the solutions, powders and thin layers. The zinc oxide structure, with the addition of nickel, reduced in size from 28 nm to 21 nm. The substituted nickel created defects, which led to peak broadening of XRD and a blue shift in UV-Vis spectrum. The photovoltaic properties are studied to understand the behavior of the structures and the current-voltage diagrams of the samples were plotted. The calculations indicate that the zinc oxide sample doped with 3% nickel, prepared using this method, exhibits the best performance as an optical photodiode in the UV range. It shows a better response in I-C curve and ideality factor. Also, the structure of this percentage has the best performance.
Food analysis is a crucial aspect of the food industry, ensuring the safety, quality, and authenticity of food products consumed by the public. To achieve this, various analytical methods are utilized, each with its own set of principles and applications. These methods play a vital role in detecting contaminants, ensuring compliance with regulations, and enhancing the overall quality of food products. The food industry is constantly evolving, and the demand for fast, accurate, and reliable analytical methods to ensure food safety, quality, and authenticity has never been greater. Traditional analytical methods have limitations such as low sensitivity, specificity, and throughput. Modern and emerging analytical techniques have been developed to overcome these limitations, providing faster, more accurate, and more comprehensive analysis of food samples. For instance, nanosensors, such as optical nanosensors for real-time detection of foodborne pathogens and toxins and nanoparticle-based multiplex nanosensors for identifying contaminants like mycotoxins and adulterants in complex food matrices, leverage nanotechnology to achieve ultra-sensitive, on-site monitoring in applications like smart packaging for spoilage prevention. Overall, food analytical methods are essential for maintaining the quality, safety, and authenticity of food products. By adhering to key principles e.g. accuracy, precision, selectivity, and sensitivity, these methods enable the food industry to meet regulatory requirements and consumer expectations. Accordingly, this review discusses the principles and applications of modern and emerging food analytical methods and techniques, with a central emphasis on the role of nanosensors in advancing food safety.
In recent years, there has been a growing interest in nanoparticles for preparing nanocatalysts used in the catalysis of many important industrial reactions. Indeed, nanotechnology provides a promising strategy for developing green nanocatalysts which are known as environment-friendly catalysts promoting the different chemical reactions. On the other hand, Nanosensors are some nanostructured materials capable of sensing (1) environmental alterations like temperature, pressure, and pH, (2) different kinds of toxins or pollutions in soils, air, and water, and (3) biochemical and metabolic changes inside cells. Therefore, nanosensors can be applicable for detecting physical and chemical factors in a variety of areas including the food industry, environmental issues (detecting pollutions), medicine (clinical diagnosis applications), biological research, and military (antiterrorism applications). Nowadays, nanomaterials are widely used for developing nanosensors, which include carbon nanotubes, polymers, metals, metal oxides, thin films, and graphene. While previous reviews have often addressed nanocatalysis or nanosensors in isolation, they rarely integrate both fields or emphasize their shared nanomaterials and applications in sustainable contexts, such as green chemistry and food safety. This chapter fills these gaps by providing a comprehensive overview of nanocatalysts and nanosensors, their current applications in various areas (with a focus on the food industry for pathogen detection, biofuel production, and preservation), and future perspectives, including emerging trends in biodegradable and recyclable nanomaterials. By bridging these domains, this review offers unique insights into interdisciplinary advancements that promote eco-friendly innovations and address challenges in scalability and toxicity. A notable portion of the review specifically highlights applications in the food industry, including pathogen detection, biofuel production, and food preservation. While previous literature may discuss these applications, this review ties together the roles of both nanocatalysts and nanosensors within this essential sector, providing insights that may have been overlooked in earlier studies. This review stands out due to its integrative approach, deep focus on sustainability and food applications, insights into regulatory environments, and critical evaluation of the potential risks associated with nanomaterials, making it a timely and relevant contribution to the field of nanotechnology.
The use of nanoparticles is a promising strategy for combating pathogenic microorganisms. This study introduces a novel hybrid nanosystem combining selenium nanoparticles (Se NPs) with curcumin-loaded chitosan nanoparticles (Cur-CS NPs) to enhance antimicrobial efficacy. The results indicate that increasing the rotation speed to 1500 rpm, the potassium iodide and ascorbic acid concentrations to 40 mM and 70 mM, respectively, leads to the production of smaller Se NPs. Furthermore, Cur-CS NPs, prepared via ionotropic gelation, exhibited a pH-dependent release profile. Two hybrid systems were developed, one combining Se-chitosan NPs (Se-CS, 73 nm) with Cur-CS NPs, and another combining Se-carboxymethyl chitosan NPs (Se-CMCS, 80 nm) with Cur-CS NPs. Both combinations demonstrated remarkable broad-spectrum antibacterial activity, with similar minimum inhibitory concentrations (0.570-1.251 mu g/mL) and minimum bactericidal concentrations against E. coli (1.251 mu g/mL) and S. aureus (9.251 mu g/mL). Furthermore, Se-CS@Cur-CS NPs demonstrated potent antiviral activity, exhibiting a two-fold higher efficacy in inhibiting SARS-CoV-2 compared to Se-CMCS@Cur-CS NPs. All systems maintained excellent biocompatibility, showing no cytotoxicity to Vero cells at concentrations up to 110 mu g/mL. These findings suggest a synergistic effect between stabilized selenium nanoparticles and Cur-CS NPs, yielding a multifunctional platform with dual antibacterial and antiviral capabilities.
A low-cost, disposable, paper-based microfluidic analytical device (mu PAD) has been developed for the measurement of nitrite and nitrate in water, with a color intensity-based response. The mu PAD was fabricated using Whatman filter paper No. 1 and a glossy, self-adhesive backing. Nitrite was measured by the Griess reaction, and for nitrate determination, nitrate was reduced to nitrite in situ on the paper with zinc nanoparticles (ZnNPs). We chose ZnNPs because they outperformed zinc microparticles (ZnMPs). The system showed linear calibration ranges of 0.01-1.25 mM for nitrite and 0.04-1.25 mM for nitrate. The detection limits were 0.003 and 0.008 mM, respectively. The method showed no interference from common ions present in water. The results of real samples were consistent with the spectrophotometric reference method, so the proposed mu PAD is suitable for rapid measurement of nitrite/nitrate concentrations at sampling sites of environmental and drinking waters.
Healing of wounds is a complicated and coordinated process with four phases, namely control of bleeding, inflammation, growth, and regeneration. Chemokines, growth inhibitors, and growth factors are all vital in establishing cell-cell contacts and the extracellular matrix. The conventional therapies include herbal treatments, specialist dressings, and interim scaffolds. Polymer scaffolds are a new innovation in wound treatment, providing a three-dimensional, temporary scaffolding for biological activities during healing. Objectives: A study attempted to speed wound healing processes by combining angiogenesis-stimulating protein (VEGF), vitamin D, silver carbon quantum dot (Ag-CQD), and henna extract (Lawsonia inermis) on polymeric nanostructures. Characteristics of the manufactured nanostructure investigated using scanning electron microscopy (SEM), Fourier-transform infrared attenuated total reflectance spectroscopy (FT-IR ATR), and X-ray Powder Diffraction (XRD). The release of Lawson and VEGF (Vascular endothelial growth factor) was measured using high-performance liquid chromatography (HPLC) and nanodrop micro-volume spectrophotometers. The nanostructures were further strengthened by immobilizing VEGF to increase angiogenesis at the wound site. Vitamin D and lawsone exhibited more than 70% favorable benefits on wound healing phases. Also silver nanoparticles demonstrate significant antibacterial activity against gram-positive and gram-negative bacteria. In terms of antibacterial efficacy, this scaffold was evaluated against Staphylococcus aureus and Escherichia coli, and the scaffold Gel/Chi/Pcl/AgCQD/Law/VEGF with 175-200 nm fibers and 10 mg of Lawson was shown to be stable at pH = 7.4. Thus, the produced scaffold exhibited considerable resistance against S. aureus, and chitosan mixed with Lawson material appeared to be extremely promising in wound healing.
beta-lactam antibiotics account for nearly 60% of global antibiotic use and are vital in treating bacterial infections by inhibiting bacterial cell wall synthesis. However, bacterial resistance has significantly increased due to the production of (3-lactamase enzymes, which hydrolyze the beta-lactam ring and deactivate the drug. To counter this resistance, beta-lactam antibiotics are often administered with beta-lactamase inhibitors. In this study, molecular docking and molecular dynamics simulations were used to identify new inhibitors of class C (3-lactamase enzymes. A total of 1177 compounds were initially selected based on structural similarity to known drugs, followed by ADMET filtering, which reduced the number to 433 candidates. These compounds were docked with five target beta-lactamase proteins. Five compounds-ZINC29247885 and ZINC22925503 (from EDTA derivatives), ZINC207616107 and ZINC220912466 (from Nacubactam analogs), and ZINC199517773 (from Vaborbactam subgroup)-showed the highest docking scores. Their performance was compared with that of beta-lactam antibiotics to evaluate their potential in combination therapies. Molecular dynamics simulations for 100 ns were conducted to assess the stability of the ligand-receptor complexes. The results suggest that these compounds are promising beta-lactamase inhibitors and could enhance the efficacy of beta-lactam antibiotics in clinical applications by overcoming bacterial resistance.
