Microscopy Techniques Research Articles

Correlative analysis of advanced microscopy techniques for metallography and corrosion microstructures of bronze phoenician coins

Correlative microscopy stands out for its ability to concurrently acquire and analyze various data types in a multimodal and multiscale environment, enabling precise localization of specific areas within samples and enhancing the accuracy and relevance of analyses. This approach showed promise in revealing the metallurgical history of ancient coins. This article focused on composition, microstructure, and manufacturing process of Phoenician-Punic copper-based alloy coins (5th–4th century BCE). The four coins studied by correlative light and electron microscopy, μ-Raman spectroscopy, and X-ray Microscopy exhibited notable differences in elemental composition and microstructures. These variations are attributed to their origin from casting, followed by striking, and subsequent recrystallization due to a more intricate corrosion process.

Microscopic Characterization of the Infectious Process, ROS Production, and Fungi Cellular Death of Alternaria alternata on Tangerine Resistant to QoIs.

Quinone outside inhibitor (QoI) fungicide resistance in Alternaria alternata populations was reported in Brazil for the first time in 2019, in São Paulo orchards, and the mutation G143A in cytochrome b (cytb) was found in resistant isolates. Our study investigated the infectious process, production of reactive oxygen species (ROS), and fungal cell death in resistant (QoI-R) and sensitive (QoI-S) A. alternata pathotype tangerine (Aapt) isolates. Morphological characterization of Aapt isolates was performed using confocal laser scanning microscopy (CLSM). Alternaria brown spot (ABS) symptoms were produced by Aapt isolates on tangelo cv. BRS Piemonte. Germination of QoI-R conidia and production of germ tubes on tangelo leaflets treated with 100 μg mL-1 of pyraclostrobin 18 h after inoculation (hai) was observed using scanning electron microscopy (SEM). At the same time, QoI-S conidial germination was inhibited on tangelo leaflets treated with pyraclostrobin. ROS production and cell death in Aapt isolates at high fungicide concentrations were observed using CLSM. QoI-S conidia exhibited high ROS production, indicating high oxidative stress. When dyed with propidium iodate (PI), QoI-S conidia emitted red fluorescence, showing cell death and confirming their sensitive phenotype. In contrast, QoI-R conidia neither produced ROS nor exhibited red fluorescence, indicating no cell death and confirming their resistant phenotype. Therefore, our findings evidence that microscopic techniques may help characterize events during fungi-plant interactions, ROS production, cell death, and Aapt phenotypes resistant and sensitive to QoIs using fluorometric protocols.

Operando Spectroelectrochemical Imaging of Concentration Fields and Tafel Kinetics in Microfluidic Electrochemical Devices.

With the development of microtechnologies for energy conversion and storage, mass transfer and micromolar concentration variations need to be measured at the microscale. These advances need to be accompanied by novel imaging techniques with the capability of achieving high spatial resolution while detecting very small signal variations (less than 0.1%). Thus, in this study, a new microscopy technique is proposed based on a combination of electrochemical impedance spectroscopy (EIS) and visible imaging spectroscopy to measure the concentration fields at the micromolar scale in operando microfluidic fuel cells (MFCs). This technique exploits EIS modulation and Fourier analysis to reduce the noise during concentration field imaging. A mass transfer model in the periodic regime is derived to validate the measurements and to estimate the Tafel kinetics and mass diffusivities during potassium permanganate reduction from only one potential measurement. The proposed imaging method and mathematical framework presented in this study can be used to study binary electrochemical reactions without gas production.

Sulfur Distribution Analysis in Lithium−Sulfur Cathode via Confined Inverse Vulcanization in Carbon Frameworks

AbstractLithium–Sulfur (Li–S) batteries are promising energy storage devices due to their high theoretical energy density. However, challenges such as the shuttling effect and volume expansion have significantly hindered their cycle life and capacity retention. Furthermore, the complex kinetic pathways in Li–S batteries call for advanced characterization techniques to unravel underlying mechanisms. In this study, a hollow porous carbon (HPC) is used as a microreactor, where inverse vulcanization occurs between 1,3‐diisopropylbenzene (DIB) and sulfur (S8), resulting in the creation of three‐dimensionally interconnected and well‐distributed S‐DIB in carbon frameworks. As a result, the dual confinement strategy imparts Li–S coin cells with remarkable cycling stability and capacity retention, exhibiting an impressive capacity of 866 mAh g−1 when returning to 0.1 C after 100 cycles of rate capability tests. Particularly, the Energy‐selective Backscattered (EsB) assisted Scanning Electron Microscope (SEM) technique as a novel approach is introduced to distinguish different lengths of polysulfides. Their distribution is visualized in the cross‐section view of the electrode in a micrometer range. These EsB images provide concrete indications of the sulfur evolution process and explain the capacity degradation during cycling.

Detection of Babesia spp., and Theileria spp., in sheep across diverse provinces of Iran

This study aimed to identify the diversity of Babesia and Theileria species in sheep across various regions of Iran using microscopic and molecular techniques, including species-specific PCR and enzymatic digestion. A total of 373 blood samples were collected from sheep during the tick vector activity period, from 2018 to 2021, in provinces such as Tehran, Alborz, Qazvin, Hamedan, West Azerbaijan, Kerman, and Fars.Results showed that 101 samples (27 %) exhibited piroplasms including 78 samples of Theileria spp. and 23 samples of Babesia spp. A molecular approach using general primers detected piroplasm parasites in 145 samples (38 %). Theileria ovis was notably present in 91 samples (24.39 %), followed by Theileria lestoquardi in 24 samples (6.43 %). Babesia ovis infection was detected in 30 samples (8.4 %). Despite extensive molecular evaluation, no other Babesia species, including Babesia motasi, were identified. Co-infections involving T. ovis and T. lestoquardi (4 samples; 1.07 %) and T. ovis and B. ovis (6 samples; 1.60 %) were observed. No Babesia spp. were detected in Kerman and Fars provinces, although T. ovis and T. lestoquardi were present.Blast analysis of the sequences indicated 100 % intra-species similarity, with inter-species similarities of 83.3 % (B. ovis and T. lestoquardi), 84.4 % (B. ovis and T. ovis), and 96.44 % (T. ovis and T. lestoquardi). In conclusion, B. ovis was the main cause of Babesiosis, while Theileriosis was predominantly attributed to T. ovis and T. lestoquardi. Molecular diagnostics play a key role in accurately distinguishing between these species, particularly in cases of co-infection involving Babesia spp. and Theileria spp.

Enhancing glycerol dry reforming performance through metal promoters: A study on 10Ni/La.Al catalyst with Mo, Sn, and Cd additions

The effect of metal promoters (Mo, Sn, and Cd) on the performance of the 10Ni/La.Al nanocrystalline catalyst in Glycerol Dry Reforming (GDR) was investigated. 2x.10Ni/La.Al (x = Mo, Sn, and Cd) catalysts were prepared using the solid-state method and 10 wt.% Ni and 2 wt.% Mo, Sn, and Cd were added to the catalyst using the impregnation method. The catalysts were characterized by BET, X-ray diffraction, temperature-programmed reduction (TPR), oxidation (TPO), Raman, and scanning electron microscopies (SEM) techniques. It was found that adding Mo caused an increase in glycerol conversion and improved the long-term stability of the 10Ni/La.Al. Furthermore, catalysts with different amounts of promoter loading (2, 4, and 6 wt%) were synthesized to evaluate the optimum amount of Mo. 4Mo.10Ni/La.Al was selected to achieve 58 % glycerol conversion and the best stability.

Temperature Studies of the LaMn2Si2 Intermetallide by the Raman Spectroscopy and Magnetic Force Microscopy Methods

Raman spectra of the LaMn2Si2 compound were obtained for the first time by Raman spectroscopy. The change of Raman spectral characteristics in the temperature range of 263–553 K was investigated. The high sensitivity of the Raman spectroscopy method to a change in the magnetic state caused by a temperature influence has been determined. A change in the spectral characteristics of the vibration mode of manganese atoms near the Curie and Neel temperatures has been revealed. The magnetic force microscopy technique was used to investigate the surface features of the LaMn2Si2 compound at room temperature. A change in the type of magnetic domain structure in LaMn2Si2 after cooling from 298 to 263 K has been found.

The Effects of Marine Fungal Asterripeptides A-C on In Vitro and In Vivo Staphylococcus aureus Skin Infection.

Objectives: This study aimed to investigate the in vitro and in vivo antibacterial and cytoprotective activities of marine fungal tripeptide derivatives with cinnamic acid moiety asterripeptides A-C (1-3). Methods: The antimicrobial and antibiofilm activities of asterripeptides A-C were tested using the Staphylococcus aureus ATCC 21027 strain. Human HaCaT keratinocytes infected with S. aureus were used for the in vitro investigation of the various aspects of the influence of asterripeptides A-C by lumino- and fluorospectrometry, ELISA, flow cytometry, Western blotting, and microscopy techniques. In the in vivo experiments, mice with burns and scalped S. aureus-infected wounds were used according to ethical committee resolution. Results: Asterripeptides A-C (10 µM) inhibited S. aureus growth and biofilm formation. Asterripeptides A-C increased the viability, proliferation, and migration of S. aureus-infected HaCaT cells and reduced the release of reactive oxygen species (ROS), NO, TNF-α, and IL-18. Asterripeptides A-C protected HaCaT cells against TNF-α-induced inflammation, decreased the transcriptional level of NF-κB in JB6 Cl41 cells, and increased the protein levels of Nrf2 and glutathione synthetase in HaCaT cells. More active asterripeptide C was tested in in vivo burn wounds and S. aureus-infected incised wounds. Asterripeptide C significantly enhanced wound healing, normalized cytokine levels and profiles of peripheral blood samples, and decreased S. aureus contamination of wounds and blood in mice with infected incised wounds. Conclusions: Taken together, these results confirm the dual antibacterial and Nrf2-dependent anti-inflammatory activities of asterripeptides A-C in in vitro and in vivo assays.

Morphology of Larger Salivary Glands in Peccaries (Pecari tajacu Linnaeus, 1758).

This work aims to study the major salivary gland morphology of peccaries during their growth. The glands were analyzed using macroscopic description, light microscopy, electron microscopy, histochemistry, and immunohistochemistry. Topographically, the salivary glands resemble other animals, including domestic animals and pigs. During growth, the parotid enlarges and mandibular gland loses weight. Histologically, the parotid has serous production, and sublingual has mucous production, resembles most species, however, mandibular gland produces mucous, unlike other animals, including pigs, which produce seromucous secretion. Histochemically, parotid produces more acidic mucins than pigs and it undergoes maturation during development; mandibular, and especially the sublingual gland, produce more acidic and basic mucopolysaccharides than pigs. The results found with transmission and scanning electron microscopy techniques corroborate the histological and histochemistry findings. The major salivary glands were positive to different lecithins (Com-A, BSA-I-B4, WGA and PNA), which were also more positive than in pigs and sheep. We conclude that collared peccaries have a salivary secretion that facilitates the digestion of carbohydrates, and biometric characteristics and positivity to lecithins that facilitate adaptation to foods with antinutritional factors.

Growth Behavior of Ni on Hydrogen-Etched WS2 Surface.

Transition metal dichalcogenides (TMDs) are 2D materials in which the layers are stacked together by van der Waals forces. Although TMDs are expected to be promising for electronic applications, forming a uniform electrode on them is challenging because of the low adhesion forces between metals and TMDs. This study focuses on improving the quality of metal electrodes by introducing atomic H to create surface defects, using Ni on WS2 as an example. The detailed effects of H etching and subsequent Ni growth were investigated using scanning tunneling microscopy (STM) and synchrotron-based X-ray photoemission (XPS) techniques. Our studies reveal that introducing point defects of ∼3.05 × 1011 cm-2 on the WS2 surface, results in a significant shift in Ni growth from the Volmer-Weber to a near Frank-van der Merwe mode. The origin of the change is the bond formation between the Ni and W atoms, which is expected to realize ohmic contact. The optimization of metal-TMD interfaces offers valuable insights for advanced applications.

Animal models in neuroscience with alternative approaches: Evolutionary, biomedical, and ethical perspectives.

Animal models have been a crucial tool in neuroscience research for decades, providing insights into the biomedical and evolutionary mechanisms of the nervous system, disease, and behavior. However, their use has raised concerns on several ethical, clinical, and scientific considerations. The welfare of animals and the 3R principles (replacement, reduction, refinement) are the focus of the ethical concerns, targeting the importance of reducing the stress and suffering of these models. Several laws and guidelines are applied and developed to protect animal rights during experimenting. Concurrently, in the clinic and biomedical fields, discussions on the relevance of animal model findings on human organisms have increased. Latest data suggest that in a considerable amount of time the animal model results are not translatable in humans, costing time and money. Alternative methods, such as invitro (cell culture, microscopy, organoids, and micro physiological systems) techniques and in silico (computational) modeling, have emerged as potential replacements for animal models, providing more accurate data in a minimized cost. By adopting alternative methods and promoting ethical considerations in research practices, we can achieve the 3R goals while upholding our responsibility to both humans and other animals. Our goal is to present a thorough review of animal models used in neuroscience from the biomedical, evolutionary, and ethical perspectives. The novelty of this research lies in integrating diverse points of views to provide an understanding of the advantages and disadvantages of animal models in neuroscience and in discussing potential alternative methods.

Stable Polymer-Lipid Hybrid Nanoparticles Based on mcl-Polyhydroxyalkanoate and Cationic Liposomes for mRNA Delivery.

Background/Objectives: The development of polymer-lipid hybrid nanoparticles (PLNs) is a promising area of research, as it can help increase the stability of cationic lipid carriers. Hybrid PLNs are core-shell nanoparticle structures that combine the advantages of both polymer nanoparticles and liposomes, especially in terms of their physical stability and biocompatibility. Natural polymers such as polyhydroxyalkanoate (PHA) can be used as a matrix for the PLNs' preparation. Methods: In this study, we first obtained stable cationic hybrid PLNs using a cationic liposome (CL) composed of a polycationic lipid 2X3 (1,26-bis(cholest-5-en-3β-yloxycarbonylamino)-7,11,16,20-tetraazahexacosane tetrahydrochloride), helper lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine), and the hydrophobic polymer mcl-PHA, which was produced by the soil bacterium Pseudomonas helmantisensis P1. Results: The new polymer-lipid carriers effectively encapsulated and delivered model mRNA-eGFP (enhanced green fluorescent protein mRNA) to BHK-21 cells. We then evaluated the role of mcl-PHA in increasing the stability of cationic PLNs in ionic solutions using dynamic light scattering data, electrophoretic mobility, and transmission electron microscopy techniques. Conclusions: The results showed that increasing the concentration of PBS (phosphate buffered saline) led to a decrease in the stability of the CLs. At high concentrations of PBS, the CLs aggregate. In contrast, the presence of isotonic PBS did not result in the aggregation of PLNs, and the particles remained stable for 120 h when stored at +4 °C. The obtained results show that PLNs hold promise for further in vivo studies on nucleic acid delivery.

Phase imaging through a single multimode fiber.

Phase imaging techniques are pivotal for achieving high-contrast visualization of unstained biological specimens in vitro, which is typically not applicable in narrow spaces. Recently, multimode fiber (MMF) has shown promise in enabling high-resolution in vivo endoscopy in biological research. Herein, we introduce a novel, to the best of our knowledge, phase imaging microscopy technique employing a single multimode fiber, showcasing remarkable capabilities in high-contrast imaging and quantitative shape reconstruction through frequency-domain modulation. Our method, validated through comparisons with reflection and phase-contrast results, demonstrates exceptional ability in imaging diverse samples, including microspheres, semiconductor chips, and oral epithelial cells. Notably, the quantitative reconstruction of surface shape achieves a sensitivity of less than 100 nm, enabling the extraction of three-dimensional information from single focal plane images. Moreover, our technique excels in contrast enhancement and defocused background suppression, presenting a promising avenue for minimally invasive, high-contrast, label-free in vivo phase imaging.

Effects of liquid accelerators on long-term mechanical strength development and microstructural changes of wet-mixed shotcrete

The significant long-term strength loss of shotcrete can greatly affect the safety and stability of underground shotcrete structures. Developing high-quality liquid accelerators remains an indispensable research direction and a viable approach to mitigate challenge. This study synthesizes three distinct kinds of liquid accelerators - alkali-free fluorine-free (GJ), alkali-free fluorine-containing (MJ), and low-alkaline (JJ) and investigates their effects on the long-term mechanical strength of wet-mixed shotcrete. Moreover, changes in the phase composition and microstructure of accelerated shotcrete were explored utilizing X-ray diffraction, thermogravimetric analysis, mercury intrusion porosimetry, and scanning electron microscopy techniques to reveal underlying mechanisms. Results indicate that accelerated cement paste and mortar with a 6 wt% fixed dosage of liquid accelerators exceeded the prescribed basic performance indices (setting time and 28-day compressive strength ratio) for shotcrete applications. Among the accelerators, the alkali-free fluorine-containing type exhibited the most beneficial effect on long-term strength, attributed to increased C-(A)-S-H formation from added Al and Si into the system. Morphological and crystal composition changes in hydrate phases, notably the transformation of ettringite to AFm and additional formation of monosulfate and hemicarbonate, increased the solid volume, refined pore structure and reduced total porosity, thus enhancing long-term strength. This study offers valuable insights into the synthesis and optimization of main accelerator components to mitigate long-term strength loss in shotcrete for practical engineering applications.

Aerodynamic and acoustic evaluation of a cylinder covered by stretched grooved fabric near critical Reynolds numbers

This study investigates aerodynamic drag and acoustic noise generated from a circular cylinder by wrapping longitudinally grooved fabrics. The fabrics are stretched to different levels to explore their potential for flow and acoustic control near critical Reynolds numbers. To analyze the fabrics' surface characteristics, 3D scanning and several microscopic techniques were employed. The parallel-mounted load cells and an array of microphones were used to measure the drag and noise at Reynolds numbers, based on cylinder diameter, ranging from \num{3.3e4} to \num{1.1e5} in an anechoic wind tunnel. Additionally, hotwire anemometry was used to examine the wake structures in the vicinity of the cylinder. The surface scanning results revealed that stretching the fabric transversely to twice its original size reduced the groove depth by approximately $54\%$ and increased the width by around $25\%$, resulting in an overall reduction of the arithmetic surface roughness $S_a$ by $18.6\%$. Based on the wind tunnel data, it was observed that a grooved fabric with higher stretch, and thus lower surface roughness exhibited a minimum drag coefficient at a higher Reynolds number, along with reduced acoustic tonal noise levels.

Liposomal AZD5363 Displays Antiproliferation Activities and Induces Apoptosis on Y79 Retinoblastoma Cancer Cells

Objectives Retinoblastoma (RB) is an aggressive intraocular cancer that usually develops during infancy and childhood. As an Akt kinase inhibitor, AZD5363 is a novel drug whose encapsulation into liposomes enhances its bioavailability and biomedical potential. In the present study, a liposomal membrane was created around AZD5363 to assess its efficacy on the Y79 cancer cell line. Materials and Methods AZD5363 nanoparticles were synthesized by the thin film hydration method. Dynamic light scattering (DLS) and field emission scanning electron microscopy (FESEM) techniques were applied to evaluate the particle size, and the morphology of the liposomal AZD5363 (Lipo-AZD5363). The MTT test was used to assess the half maximal inhibitory concentration (IC50) of Lipo-AZD5363, and the cytotoxic effects of Lipo-AZD5363 and doxorubicin (Dox) were investigated on the Y79 cell line. Flow cytometry was used to study apoptotic induction in selected groups. Also, the PTEN/AKT/FOXO1 gene expression level was measured using quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Results Treatment with Lipo-AZD5363 inhibited the proliferation of Y79 RB cancer cell line in a dose-dependent manner. Lipo-AZD5363, at a lower concentration, was significantly more cytotoxic than Dox in terms of enhanced cell death (p < 0.05).Furthermore, flow cytometry showed that Lipo-AZD5363 and Dox induce apoptosis in these cells. However, the number of apoptotic cells in the Lipo-AZD5363 group was clearly higher than that in the Dox group (p < 0.001). Real-time PCR analysis indicated that Lipo-AZD5363 treatment resulted in an increase in PTEN and FOXO1 gene expression and a decrease in AKT gene expression. Our study revealed that all results were statistically more significant in the Lipo-AZD5363 group than in the Dox group (p < 0.01, <0.01, and <0.001, respectively). Conclusion Lipo-AZD5363 inhibits proliferation and promotes apoptosis of RB cells by inhibiting the PI3K/AKT signaling pathway. Thus, Lipo-AZD5363 may be a promising candidate for cancer therapy. However, more experimental evidence is needed for its use in the pharmacological treatment of RB.

Biogenic Silver Nanoparticles (AgNPs) Ameliorates Oxidative Biomarkers in Type-2 Diabetic Rats: In vitro and In vivo Report

Objective: Nanoparticles (NPs) are reliable biological tools for curative purposes through their application in nanomedicine. The present study synthesized and characterized silver nanoparticles (AgNPs) from Tetrapetra tetrapleura fruit. The investigation aims to examine the antidiabetic effect of the AgNPs using in vitro and in vivo models. Methods: Briefly, the synthesized AgNPs were confirmed by the application of ultraviolet-visible (UV-Vis) spectroscopy, and five other techniques, viz; transmission electron microscopy (TEM) techniques, Fourier transform infrared (FTIR) spectroscopy, energy dispersive X-ray spectroscopy (EDX), X-ray diffraction analysis (XRD) and scanning electron microscope (SEM). The in vitro model assay investigated the scavenging effect of AgNPS on 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion (O2ˉ), hydroxyl anion (-OH), ferric reducing antioxidant power (FRAP), and α-amylase/α-glucosidase inhibitory activity. The in vivo model involving rats-induced type-2 diabetes with streptozotocin (STZ) was divided into six (6) groups of seven (7) rats each to assess antioxidative parameters. Results: The AgNPs scavenged free radicals (DPPH) and moderately inhibited (O2ˉ), hydroxyl anion (-OH), reduced ferric to ferrous ions, and inhibited both α-amylase and α-glucosidase activity with increasing concentrations. Similarly, AgNPs ameliorated oxidative stress imposed by type 2 diabetes on the rats’ tissues significantly (p < 0.05), depleting total cholesterol, low-density lipoprotein (LDL), and increased total protein composite and high-density lipoprotein (HDL) contents. The AgNPs enhanced catalase and superoxide dismutase, reduced glutathione (GSH), and, concomitantly, decreased malondialdehyde (MDA) levels in the tissue homogenate. Conclusion: These findings provide scientific evidence for the first time, finding the application of a biogenic compound synthesized from T. tetrapleura fruit in the treatment of type 2 diabetes.

The benthic and epiphytic marine dinoflagellates of Aotearoa New Zealand and Rangitāhua Kermadec Islands, an updated checklist from 2018 to 2024

ABSTRACT A checklist collating records of New Zealand’s benthic and epiphytic dinoflagellate species was published on-line in 2018 [Rhodes L, Smith KF. 2019. A checklist of the benthic and epiphytic marine dinoflagellates of New Zealand, including Rangitāhua/Kermadec Islands. N Z J Mar Freshw Res. 53:258–277. doi:10.1080/00288330.2018.1492425]. Over the last six years, seventeen species from nine genera (three newly reported genera) have been documented, including sand-dwelling species. Isolation and identification of species using traditional microscopic techniques combined with analysis of DNA sequencing data has been supplemented by high-throughput sequencing techniques (i.e. metabarcoding). Toxin data, based on liquid chromatography mass spectrometry (LC-MS/MS), and toxicity of isolates are included where applicable. Forty-two benthic and epiphytic dinoflagellate genera, including genera having benthic life stages, have now been recorded in Aotearoa New Zealand coastal waters including Rangitāhua Kermadec Islands (new record genera in bold): Adenoides , Alexandrium, Amphidinium, Archaeperidinium, Azadinium, Biecheleria, Blastodinium, Bysmatrum, Cachonina, Coolia, Crypthecodinium, Cryptoperidiniopsis, Dinophysis, Durinskia, Ensiculifera, Fukuyoa, Fragilidium, Gambierdiscus, Gonyaulax, Gymnodinium, Gyrodinium, Heterocapsa, Karenia, Karlodinium, Kryptoperidinium, Lepidodinium, Ostreopsis, Pelagodinium, Pentapharsodinium, Pfiesteria, Polarella, Prorocentrum, Protodinium, Protoperidinium, Pseudadenoides , Pseudopfiesteria, Scrippsiella, Symbiodinium, Thecadinium , Togula, Vulcanodinium and Woloszynskia.

Green synthesis of Oscimum Sanctum mediated silver nanoparticles to fabricate sensors for hydrogen peroxide detection

In this study, silver nanoparticles (Ag NPs) of an average size of ∼15 nm have been produced using the green synthesis technique with Oscimum Sanctum leaf extract. Further, these nanoparticles have been used to prepare electrodes for electrochemical sensors to monitor hydrogen peroxide. Hydrogen peroxide sensors have many applications in different sectors, such as medical, agriculture, and industry. The optical and structural characteristics of the Ag NPs have been investigated by UV–visible absorption spectroscopy and XRD patterns. Particle size, shape, and morphology of as-synthesized Ag NPs have been analyzed using transmission and scanning electron microscopic techniques. These nanoparticles were deposited onto an indium-tin-oxide glass substrate using the electrophoretic technique, which was used as an electrode to assess the electro-oxidation of Ag NPs by cyclic voltammetry. The sensitivity of the sensor has been estimated to be 4.16 µA/mM-cm2. The limit of detection of the sensor is estimated to be 40 µM within the linear range of 5–28 mM. The lattice parameter, interplanar spacing, and crystallite size of Ag NPs have been quantified and estimated against pH variation.

Explore the effect of magnesium oxide nanoparticles decorated graphene oxide hybrid nanofillers reinforced polyaniline ternary nanocomposites on optical, thermal, and dielectric properties

The Neem (Azadirachta indica) leaves utilized for the synthesis of magnesium oxide nanoparticles (MgONPs) are readily available and pose little risk of harm. The MgONPs@GO hybrid nanofillers are synthesized through in situ method and is reinforced with polyaniline (PANI) to enhance its electrical characteristics and thermal stability. The UV-visible spectroscopy demonstrates the formation of a charge transfer complex in the PANI/MgONPs@GO ternary nanocomposites. The presence of functional groups in the PANI/MgONPs@GO ternary nanocomposites was detected using Fourier transform infrared (FTIR) spectroscopy. The crystalline phases of the PANI/MgONPs@GO ternary nanocomposites were validated using x-ray diffraction (XRD) investigation. The scanning electron microscopy (SEM) technique was used to investigate the nanostructured morphology of the PANI/MgONPs@GO ternary nanocomposites. The thermogravimetric analysis (TGA) revealed that the PANI/MgONPs@GO ternary nanocomposites exhibited greater thermal stability compared to the pure PANI. The AC conductivity (σ ac), dielectric permittivity (ε′), and dielectric loss (tanδ) of PANI/MgONPs@GO ternary nanocomposites exhibit a substantial increase compared to pure PANI.