International Nano Letters is a peer-reviewed open access journal, covering fundamental and applied research in all disciplines of science, engineering and medicine. The overall aim of the International Nano Letters is to bring science and applications together on nanoscale and nanostructured materials with emphasis on synthesis, processing, characterization, and applications of materials containing true nanosize dimensions or nanostructures that enable novel/enhanced properties or functions. It is directed at both academic researchers and practicing engineers. This journal operates on an open access model and charges an Article Processing Charge (APC) to cover the costs of publication and ensure free and permanent access to published articles. We are committed to supporting researchers worldwide and offer APC waivers for authors from low- and middle-income countries, as well as in cases of financial hardship. Waiver requests are considered on a case-by-case basis and do not influence editorial decisions. For more information on APCs and waiver eligibility, please visit our APC & Waivers Policy page. Journal DOI: 10.57647/inl Journal Abbreviation: Int. Nano Lett. Journal Title Acronym: INL Journal Owner: Islamic Azad University Publisher: Islamic Azad University, Co-publishing, OICC Press, UK Editor-in-Chief: Bijan Ranjbar, PhD Director-in-Charge: Jamshid Sabbaghzadeh, PhD Managing Editor: Atefeh Ghaderi, PhD
Recent Insights into Biodegradable Nanocomposites for Food Packaging Applications: Prospects and Challenges
Biodegradable nanocomposites have emerged as promising alternatives to conventional petroleum-based food packaging materials, offering enhanced mechanical strength, improved barrier performance, and active functionalities such as antimicrobial activity. By combining biopolymer matrices with nanoscale fillers, these materials aim to maintain food quality while reducing environmental impact. Numerous studies demonstrate that biodegradable nanocomposites can satisfy key functional requirements of traditional packaging while providing additional performance advantages. However, despite significant laboratory-scale advancements, several critical challenges continue to limit large-scale implementation. These include scalable manufacturing and nanofiller dispersion control, regulatory compliance, migration safety evaluation, cost competitiveness, and long-term environmental assessment. Addressing these interconnected constraints is essential for translating material innovation into practical packaging solutions. This review aims to bridge the gap between laboratory-scale material development and real-world packaging applications by addressing technical, safety, and commercialization constraints. By examining current limitations and emerging solutions, the review provides a realistic outlook on the future integration of biodegradable nanocomposites into sustainable food packaging systems.
Copyright (c) 2026 Maryam Salehian, Zeinab Salehi, Kianoush Khosravi-Darani (Author) https://creativecommons.org/licenses/by/4.0
Distance-Based Colorimetric µPADs for Nickel Detection: Effect of Cover Materials, Reagent Loading, and Data Normalization
Distance-based microfluidic paper-based analytical devices (pPADs) provide instrument-free quantification for metal ions, yet cross-study comparisons are hindered by differences in geometry, paper type, reagent loading, and sample volume. In this work, transparent-sheet-covered pPADs were fabricated on Whatman Grade 42 using a simple impregnation method, and the selective Ni–dimethylglyoxime (Ni–DMG) reaction at pH 10.2 generated a reddish-pink precipitate whose migration length represented the analyte concentration. Four Ni(II) levels (20 − 80 ppm) and three DMG loadings (20, 40, and 60 mM) were tested (???? = 10, 5 pL per sample). Band length increased with Ni(II) concentration but decreased with higher DMG, revealing a trade-off between signal and reagent excess. To compare with wax-printed pPADs in the literature, a channel-width correction and dimensionless length normalization were applied, while data were expressed in terms of Ni(II) amount (nmol). The normalized curves showed close agreement in the overlapping range despite differences in paper grade and channel width. The Wilairat model fitted the data well (????2 > 0.95), with increasing DMG elevating the reagent parameter and lowering the asymptotic distance. Overall, the reproducible, low-cost platform and the introduced normalization framework offer a practical route to harmonize distance-based colorimetric Ni(II) detection across various pPAD designs.
Microfluidic paper-based analytical devices
Copyright (c) 2026 Elnaz Ghahremani, Leila Vafajoo, Azizollah Shafiekhani (Author) https://creativecommons.org/licenses/by/4.0
Effect of Pulsed Laser Irradiation on Perovskite/TiO2 Nanoparticles
Perovskite layers are key nanoscale absorbers in a wide range of optoelectronic devices, driving intense research into their deposition control, crystallization kinetics, and interfacial nanoengineering. In this work, we investigate the effects of nanosecond-pulsed Nd:YVO4 laser irradiation (355 nm) on the structural and optical properties of perovskite layers integrated with TiO2 nanoparticles. Nanoscale modifications induced by laser processing are systematically analyzed through optical transmission, photoluminescence (PL), surface morphology, and elemental composition measurements. The results reveal laser fluence as a decisive parameter: Low fluence deteriorates optoelectronic performance by forming a defective surface dead layer via increased nanoscale roughness, whereas higher fluence enhances optical transmittance through controlled nanoscale ablation and film thinning. Moreover, the incorporation of a mesoporous TiO2 nanoparticle scaffold plays a critical role in maintaining bandgap stability during laser exposure, underscoring its protective function against localized thermal decomposition. These findings demonstrate that laser-matter interactions at the nanoscale can be precisely tuned to engineer perovskite layers for targeted optoelectronic device applications.
Copyright (c) 2025 Nahid Ghazyani, Vahid Kamrani Pouya (Author) https://creativecommons.org/licenses/by/4.0
Nonlinear Dynamical Band Structure Induced by Frequency-Dependent Nonlinearity in Duffing Oscillators
We demonstrate that a nonlinear medium whose nonlinear susceptibility is explicitly frequency-dependent such as graphene-exhibits nonlinear dispersive dynamical states governed by the Duffing equation. These states selectively suppress or support certain frequency components of the driving field, forming a nonlinear band structure without any spatial periodicity. This reveals a new mechanism of nonlinear frequency filtering originating solely from the dynamical response of the nonlinear oscillator. The nonlinear dispersive medium modifies the effective Floquet quasi-energy landscape of the driven Duffing oscillator. The Jacobi elliptic solutions exist only in regions where the nonlinear Floquet modes are stable, forming frequency-selective “nonlinear Floquet bands”. Outside these bands the Floquet multipliers diverge, resulting in forbidden frequencies.
Copyright (c) 2026 Morteza Abdollahi Sharif, Mehdi Borjkhani, Hadi Borjkhani (Author) https://creativecommons.org/licenses/by/4.0
Luminescent ZnWO4:Ag Fibers as Flexible Platforms for Smart Radiation Sensitive Textiles
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 crystallinitydue to lattice distortion. Raman spectroscopy further verified the preservation of characteristic WO24− vibrational modes. FESEM observations revealed the successful formation of continuous microfibers with average diameters of approximately 12 μm for pristine ZnWO4 fibers and 15 μm 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 ∼ 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.
Copyright (c) 2025 Sanaz Alamdari, Amir Hossein Jabbar Sadooni, Somayeh Salmani Shik (Author) https://creativecommons.org/licenses/by/4.0
Structural Tuning of ZnO Nanorods via Seed-Layer Engineering for High Speed n-ZnO/p-Si UV Photodetector
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 μm. 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.
Copyright (c) 2026 Samaneh Jabbarivand, Moahammad Hossein Majles Ara, Soraya Muosavi, Ali Kazempour (Author) https://creativecommons.org/licenses/by/4.0
Optical Route for Testosterone Hormone Sensing Exploiting BlochWaves in One Dimensional Photonic Crystal
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-μL 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°, while the highest concentration (of 200 mM) was spotted at 51.7°. 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.
Copyright (c) 2025 A. Shirshahi, D. Cheraghian, M. Ghasemi, Seyedeh Mehri Hamidi, Pankaj Kumar Choudhury (Author) https://creativecommons.org/licenses/by/4.0
Electrospun PAN/ZnO/CuO Nanofibers: Investigation of Microstructure and Antibacterial Activity
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.
Copyright (c) 2025 Sara Azarakhsh, Mohammad Hossein Majles Ara, Reza Beiranvand (Author) https://creativecommons.org/licenses/by/4.0
Tailoring Electronic and Magnetic Behaviour of ZnS via (Sm, Co) Co-Doping for Spintronics Applications
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.
Copyright (c) 2025 D. Saikia, J. P. Borah (Author) https://creativecommons.org/licenses/by/4.0
Sonneratia caseolaris-Mediated Silver Nanoparticles: Characterisation and Antibacterial Activity Against Edwardsiella tarda from Diseased Freshwater Fish
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 β-haemolytic strain (ET10). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined to be 2.5 μg/mL. This study suggests that SC-AgNPs has the potential as an alternative to antibiotics to reduce the risk of antibioticresistance in aquaculture.
Copyright (c) 2025 Alia Syafiqah Aznan, Kok Leong Lee, Wan Nurhafizah Wan Ibrahim, Nur Azna Saari, Mohamad Tajuddin Abdul Manaf, Norhidayah Mohd Ahyat, Ruhil Hayati Hamdan, Musa Nadirah, Yeong Yik Sung, Alyza Azzura Abd Rahman Azmi, Faizah Shaharom-Harrison, Rossita Shapawi, Houjun Pan, Musa Najiah (Author) https://creativecommons.org/licenses/by/4.0
Nano Herbal Therapeutics: A Dual-Edged Sword – Comprehensive Insights into Advantages, Challenges, and Future Prospects
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 cost-effectiveness. 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.
Copyright (c) 2025 Entesar E. Hassan, Dalia Mamdouh Mabrouk, Sekena H. Abdel-Aziem (Author) https://creativecommons.org/licenses/by/4.0
Structural Investigation of the Graphene TriangularNanostructure Edges and Energy Band Calculation
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.
Copyright (c) 2025 Alireza Dadkhah Tehrani, Babak Efafi, Mohammad Hossein Majles Ara (Author) https://creativecommons.org/licenses/by/4.0
Plasmon–Exciton Coupling in Flexible Ag/Fluorescein Hybrid Nanostructures for Enhanced Fluorescence Applications
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.
Copyright (c) 2025 Zainab Adnan, Zainab Ahmed, Zahraa Musafir Abd, N. S. Shnan (Author) https://creativecommons.org/licenses/by/4.0
Quantum Dot-Integrated Perovskite Solar Cells: A Pathway to Enhanced Light Harvesting and Stability
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 ∼ 26% while improving long-term stability. This review surveys recent progress in QD PSCs 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.
Copyright (c) 2025 Promud Konch, Prerona Singha, Pradip Kumar Kalita, Sagar Bhattarai (Author) https://creativecommons.org/licenses/by/4.0
Formulation and In Vitro Evaluation of Metformin-Loaded Chitosan Nanoparticles Using Ionic Gelation Technique
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.
Copyright (c) 2025 Airemwen Collins Ovenseri, Ahmad Saleh Malkawi, Obarisiagbon A. Johnbull, Uhumwangho U. Michael (Author) https://creativecommons.org/licenses/by/4.0
Enhancing Hyperthermic Oncology: A Computational Approach to Optimize Fe3O4@Au core-shell Configurations for Targeted Tumor Therapy
This work focuses on Near- Infrared region and an incident laser with a wavelength of 808 nm to study the numerical optimization of the Fe3O4@Au core-shell nanostructure for enhanced hyperthermia treatment, specifically targeting skin cancer. Utilizing the simulation capabilities of COMSOL Multiphysics, we meticulously computed the optical properties-absorption, scattering, and extinction coefficients-of these nanostructures across varying incident wavelengths and core-to-shell ratios. Our findings reveal a pivotal dependency of maximum absorption rates on both the core-to-shell ratio and the parameters of the incident laser, marking a significant stride in the customization of hyperthermia therapy. Crucially, the study harnesses local temperature elevation as a therapeutic index for skin cancer treatment. The thermal mapping achieved delineates a stark contrast between the peak temperature of 56 °C within the tumor and a controlled 37 °C in the surrounding healthy tissue, showcasing the potential for targeted thermal ablation with minimal collateral damage. The graphical representations not only corroborate the theoretical model but also serve as a beacon for future clinical applications, promising a new horizon in the minimally invasive treatment of cancer with the utmost precision and minimal undesired effects.
Copyright (c) 2024 Somayeh Salmani, Somayeh Rahbari, Fereshteh Shafiepour (Author) https://creativecommons.org/licenses/by/4.0
Nanomaterials in Diabetic Wound Dressing: A Mini Review
Diabetes is one of the most prevalent worldwide chronic diseases. This disease is result of impaired insulin production or function which leads to the sustainable high blood glucose. Diabetes causes numerous problems including neuropathy, vascular disorders and chronic infections. One of the most known infections are diabetic wounds, particularly foot ulcers. Diabetes delays the healing process leading to a non-healing wound and finally this disease can lead to amputation. Nanotechnology has introduced innovative approaches to treating these wounds. In fact, presence of nanomaterials in diabetic wound dressing can decrease healing time even up to 50%. Different kinds of nanomaterials including inorganic, organic, biological and composite nanostructures, were used in diabetic wound dressings. This review article explores the impact of nanomaterials on diabetic wound treatment in recent decade. In this way, different kinds of implemented nanomaterials in diabetic wound dressings and their mechanism of action, advantages, limitations and challenges are compared. Overall, nanomaterials operate through controlled drug release, stimulation of cell growth, and inflammation reduction.
Copyright (c) 2024 Razieh Sanjari, Mohsen Forozanfar, Fatemeh Honarasa, Mohammad Amin Edalatmanesh, Heydar Aqababa (Author) https://creativecommons.org/licenses/by/4.0
Preparation of a New Inexpensive Paper-Based Sensor for the Detection of Nitrite and Nitrate Species in Water
A low-cost, disposable, paper-based microfluidic analytical device (µPAD) has been developed for the measurement of nitrite and nitrate in water, with a color intensity-based response. The µPAD 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 µPAD is suitable for rapid measurement of nitrite/nitrate concentrations at sampling sites of environmental and drinking waters.
Copyright (c) 2024 Zahra Moradi, Parvaneh Ghaderi-Shekhi Abadi, Kambiz Varmira, Mohammad Joshaghani (Author) https://creativecommons.org/licenses/by/4.0
Molecular Docking and Molecular Dynamics Simulations to Introduce New Inhibitors for Ambler Class C of β-lactamase Enzymes
β-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 β-lactamase enzymes, which hydrolyze the β-lactam ring and deactivate the drug. To counter this resistance, β-lactam antibiotics are often administered with β-lactamase inhibitors. In this study, molecular docking and molecular dynamics simulations were used to identify new inhibitors of class C β-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 β-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 β-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 β-lactamase inhibitors and could enhance the efficacy of β-lactam antibiotics in clinical applications by overcoming bacterial resistance.
Copyright (c) 2024 Bahare Noohi, Maedeh Moayed Naseri, Mansour Zahedi (Author) https://creativecommons.org/licenses/by/4.0
Effect of Ni-Doping on the Structural and Optical Properties of ZnO Nanoparticles by Sol-Gel Method
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 SEManalyses 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.
Copyright (c) 2024 Elahe Moeini Sede, Mohammad Hossein Majles Ara, Seyedeh Soraya Mousavi, Fereshteh Rasouli Asl (Author) https://creativecommons.org/licenses/by/4.0
Selenium Chitosan and Selenium Carboxymethyl Chitosan Nanoparticles Combined with Curcumin Chitosan Nanoparticles to Enhance Antibacterial and Antiviral Activities
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 µg/mL) and minimum bactericidal concentrations against E. coli (1.251 µg/mL) and S. aureus (9.251 µg/mL). Furthermore, SeCS@Cur-CS NPs demonstrated potent antiviral activity, exhibiting a two-fold higher efficacy in inhibiting SARS-CoV-2 compared to SeCMCS@Cur-CS NPs. All systems maintained excellent biocompatibility, showing no cytotoxicity to Vero cells at concentrations up to 110 µg/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.
Copyright (c) 2024 Zahra Tavakoli, Reza Aalizadeh, Khosro Khajeh, Bijan Ranjbar (Author) https://creativecommons.org/licenses/by/4.0
Zinc- poly aniline- Palladium core shell for Non-enzymatic electrochemical detection of Acetaminophen
In this work, the electrochemical performance of ZnO-(3-Aminopropyl)triethoxysilane (APTES) was studied, along with poly(2-anilinoethanol)-(M-ZnO-P2AE NC) embedded with Pd nanoparticles for detecting Acetaminophen. The core-shell structure was synthesized in a three-step process: solvothermal synthesis, hydrothermal treatment, and surface decoration with Pd nanoparticles. Physicochemical analysis shows that Pd decoration enhances the optical and electrochemical performance of the composite, with high thermal stability. These results suggest that Pd nanoparticles alter the electronic structure of M-ZnO-P2AE NC, as confirmed by diffuse reflectance spectroscopy analysis. Electrochemical detection of Acetaminophen was conducted in the presence of other biomaterials to evaluate the selectivity of the electrode. The electrochemical analysis indicates that the prepared core-shell can effectively monitor Acetaminophen, with a detection limit of 10 nM.
Copyright (c) 2024 Mohammad Nikfarjam, Hamed Javadi, Javad Shabani Shayeh, Roya Sedghi (Author) https://creativecommons.org/licenses/by/4.0
Emerging Food Analytical Methods: Role of Nanotechnology
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.
Copyright (c) 2024 Hamed Ahari, Sima Moradi, Kianoush Khosravi-Darani (Author) https://creativecommons.org/licenses/by/4.0
Synergistic Effect of Nano-TiO2 and CNTs on the Mechanical and Microstructural Properties of Cement–Silica Fume Stabilized Soils under Freeze–Thaw Cycles
Soft clay soils with high water content and low bearing capacity pose serious challenges for geotechnical infrastructures, particularly in cold regions where repeated freeze-thaw cycles accelerate structural degradation. Although various nano-additives have been utilized to enhance soil stabilization, the synergistic effect of nano titanium dioxide (nano-TiO2) and carbon nanotubes (CNTs) in cement–silica fume systems has not yet been systematically evaluated. In this study, the combined influence of nano-TiO2 and CNTs on the mechanical and durability properties of cement–silica fume stabilized soils was investigated through an extensive experimental program involving 243 specimens prepared with 12% cement and varying silica fume (5−20%), nano-TiO2 (1−5%), and CNT (0.15−0.45%) contents, cured for 7, 28, and 56 days. The specimens were subjected to 25 freeze–thaw cycles at a constant moisture content of 40%, exceeding the liquid limit of the soil.Results indicated that the silica fume–cement mixtures improved unconfined compressive strength (UCS) by an average of 85% compared to cement alone, while the incorporation of nano-TiO2 and CNTs further increased UCS by up to 142%. Water absorption decreased by approximately 85%, and strength loss under freeze–thaw cycles was minimal. These findings highlight the novelty and practical significance of the nano-TiO2–CNT composite in enhancing both the mechanical strength and frost durability of cement-stabilized soils, providing a sustainable approach to subgrade stabilization in cold climates.
Copyright (c) 2024 Hamed Ajorloo, S. Mohammad Mirhosseini, Emadaldin Hezavehi, Ali Hassani Joshaghani (Author) https://creativecommons.org/licenses/by/4.0
Nanotechnology-Enhanced Polymer Scaffolds with Antibacterial and Angiogenic Properties on Diabetic Wound Healing
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.
Copyright (c) 2024 Hayder Sudan Abbas Obaid, Fateme Mirzajani, Amin Hamidi, Iliya Fattahiyan, Meysam Omidi (Author) https://creativecommons.org/licenses/by/4.0
Isotherm Investigation and Assessment of the Adsorption Efficacy of Zinc Ions on Natural Zeolite and Zeolite Modified with Anionic (SDS) and Cationic (CTAB) Surfactants
This investigation examines the efficacy of natural clinoptilolite zeolite and its modified variants, utilizing the cationic surfactant hexadecyltrimethylammonium bromide (CTAB) and the anionic surfactant sodium dodecyl sulfate (SDS), for the removal of zinc ions from aqueous solutions. Solutions containing zinc at varying concentrations were formulated, and the residual ion concentrations post-adsorption were assessed utilizing atomic absorption spectroscopy. The findings demonstrate that surface modification with anionic SDS surfactant dramatically enhances adsorption performance, achieving an exceptional capacity of 18.56 mg/g at 200 mg/L initial concentration. This represents a substantial threefold enhancement compared to natural zeolite (5.57 mg/g) and a notable fivefold superiority over CTAB-modified zeolite (3.85 mg/g), highlighting the crucial influence of surfactant charge characteristics. The adsorption isotherm analyses suggested that the adsorption process conformed to a monolayer model. Nonlinear regression analysis of the empirical data against various isotherm models indicated that the Fritz-Schlunder model offered the most accurate representation for the natural zeolite, while the Weber-van Vliet model exhibited optimal conformity for both surfactant-modified systems. In summary, the results of this study indicate that the modification of clinoptilolite zeolite with the anionic surfactant SDS constitutes a promising approach for augmenting the efficiency of zinc ion removal from aqueous systems.
Copyright (c) 2024 Rashid Zandlashani, Abbas Kasaei (Author) https://creativecommons.org/licenses/by/4.0
The Effect of Applied Electric Field on Hydrogen Incorporation During the Formation of Au Nanoparticles Fabricated by Laser Ablation
In the present study, gold nanoparticles (NPs) were fabricated by pulsed laser ablation (PLA) method in distilled water environment under different external electric field strengths. The effect of the electric field on the characteristics of produced NPs was traced through X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) and transmission electron microscopy (TEM). Optical properties were studied by UV-visible spectroscopy. The XRD results showed an orthorhombic lattice, alongside the typical cubic structure of Au, which was attributed to the hydrogen incorporation in the crystalline structure of Au nanoparticles. The interaction between hydrogen and gold did not vary linearly with the increased of applied electric field. At an electric field of 20 V/cm, this interaction was almost negligible. Furthermore, the peak observed at around 2000 cm−1 in the FT-IR spectrum provided additional evidence for possible Au-H interactions. Based on the TEM images, some non-spherical shapes such as nanorods were successfully synthesized under higher electric field strengths. Moreover, the interaction between hydrogen and gold likely induced a slight blue shift in the UV-Vis spectrum. The formation of Au hydride makes our sample a promising candidate for use as anoptical hydrogen sensor; however, further research is needed.
Copyright (c) 2024 Parisa Ojaroody, Mohammadreza Hantehzadeh, Elham Darabi (Author) https://creativecommons.org/licenses/by/4.0
Water Chemical Treatment by Photocatalytic Activity of Graphene Oxide–Decorated Titanium Dioxide/Ag Nanocomposite
In the present study, gold nanoparticles (NPs) were fabricated by pulsed laser ablation (PLA) method in distilled water environment under different external electric field strengths. The effect of the electric field on the characteristics of produced NPs was traced through X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) and transmission electron microscopy (TEM). Optical properties were studied by UV-visible spectroscopy. The XRD results showed an orthorhombic lattice, alongside the typical cubic structure of Au, which was attributed to the hydrogen incorporation in the crystalline structure of Au nanoparticles. The interaction between hydrogen and gold did not vary linearly with the increased of applied electric field. At an electric field of 20 V/cm, this interaction was almost negligible. Furthermore, the peak observed at around 2000 cm−1 in the FT-IR spectrum provided additional evidence for possible Au-H interactions. Based on the TEM images, some non-spherical shapes such as nanorods were successfully synthesized under higher electric field strengths. Moreover, the interaction between hydrogen and gold likely induced a slight blue shift in the UV-Vis spectrum. The formation of Au hydride makes our sample a promising candidate for use as an optical hydrogen sensor; however, further research is needed.
Copyright (c) 2024 Pegah Mosayebi, Davoud Dorranian, Kourosh Behzad, Amir Hossein Sari (Author) https://creativecommons.org/licenses/by/4.0
Multilayer Propylenidene for Optoelectronic Applications: A First-Principles Study of Electronic and Optical Characteristics
This study investigates a novel two-dimensional carbon allotrope, propylenidene (PPD). The electronic and optical properties of monolayer, bilayer, and trilayer configurations of PPD were explored using den sity functional theory (DFT). The results reveal metallic behavior in all layered forms, accompanied by highly anisotropic optical responses. Notably, the in-plane polarization of incident light induces strong optical absorption, high dielectric constants, and exceptional optical conductivity. The layers also exhibit significant transparency due to high transmission coefficients. Furthermore, these properties exhibit clear layered-dependent tuning. The findings facilitate the rational design of carbon-based materials with tailored optical properties, paving the way for high-efficiency optoelectronic devices and emerging electro-optical technologies.
Copyright (c) 2024 Roya Majidi, Hamid Eftekhari, Ahmad. I. Ayesh (Author) https://creativecommons.org/licenses/by/4.0
Designing and Optimizing Bioactive Bone Dressing for Tooth Socket Preservation and Regenerative Dentistry Application: In Vitro Study
To address the challenge of preserving sufficient alveolar bone volume and quality following tooth extraction, this in vitro study presents the design and optimization of a bioactive scaffold composed of carboxymethyl cellulose (CMC), alginate (Alg), and tricalcium phosphate (TCP). This composite aims to facilitate post extraction socket healing and promote osteogenesis. The scaffold was fabricated using freeze-drying to achieve a porous, sponge-like structure. Sodium alginate and CMC were mixed at a 30:70 ratio, with TCP incorporated at 3% wt% and crosslinked using a 0.5 M calcium chloride solution. The formulation was subjected to controlled freezing and lyophilization steps to enhance porosity and mechanical integrity. Characterization studies confirmed a highly porous structure (79% porosity) with interconnected pores, as visualized by SEM. Mechanical testing revealed improved compressive strength due to TCP incorporation, while FTIR and XRDanalyses confirmed polymer bonding and the presence of TCP, respectively. Degradation testing showed a slow initial breakdown followed by accelerated degradation, leading to complete scaffold resorption by day 28. Biological assays, including MTT, Alizarin Red staining, and ALP activity, demonstrated the scaffold’s excellent biocompatibility and ability to support cell proliferation, migration, and enhanced calcium deposition. These findings suggest that the scaffold has potential for promoting osteogenesis in vitro, warranting further investigation for its possible application in alveolar bone regeneration.
Copyright (c) 2024 Elahe Houshmand, Sadaf Javadpour, Mohammadhossein Ehsani, Mike Sabeti, Javad Mehrani Sabet, Seyyed Behnam Abdollahi Boraei, Sattar Yousef, Behzad Houshmand (Author) https://creativecommons.org/licenses/by/4.0