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COVID‐19 the most devastating pandemic of the current millennium, can survive from hours to months in environment, devices, and surface. Its transmission by asymptomatic carriers has significantly strained the existing testing resources. At present, there are no clinically proven therapeutic methods that effectively inhibit the effects of this virus. Nanoparticles (NPs) have been extensively utilized in various medical applications, including biosensing, drug delivery, imaging, and antimicrobial/antiviral treatment. Synthetic NPs can closely resemble the virus and strongly interact with its proteins due to their similar morphology. Therefore, NP‐based strategies for combating this virus hold immense potential and may reduce the survivability of the virus in the environment due to unique physicochemical features and surface modification properties. In this study, antiviral properties of silver (Ag), copper oxide (CuO), cobalt oxide (Co3O4), and cerium oxide (CeO2) NPs besides Ag and Cu sheets against COVID‐19 in nasopharyngeal samples were investigated. All NPs suspensions were prepared in Virus Transporter Media (VTM) in 25, 50, and 100 mg/mL concentrations, additionally, Cu and Ag sheets were added to SARS‐CoV‐2 virus pooled and then incubated at room temperature. Viral RNA was extracted from those suspensions after different incubation times and concentrations and quantitative polymerase chain reaction (qPCR) analysis was performed. For virucidal activity evaluation, the estimated lysed virus copy number was assessed according to the pooled virus sample serial dilution and eventually based on changes in the cycle threshold (CT) of qPCR. According to CT number changing after incubation of NPs with pooled virus sample, CuO NPs had the greatest virus inactivation on virus lysis at all concentrations and times while Co3O4 NPs showed moderate antiviral activity (P<0.05). The antiviral activity of other NPs was less than CuO and Co3O4 and were almost identical at similar concentrations and times. Cu and Ag sheets have shown a direct linear relationship between incubation time and antiviral activity. Cu nanoparticles had significant destructive effects on the SARS‐CoV‐2 virus among all nanoparticles, and the Cu sheet had considerably less antiviral activity than its own Cu NPs. These findings might make it helpful to use CuO NPs in masks, and air/water filters, make coated surfaces with effective NPs, and manufacture disinfectant solutions to combat coronaviruses and other viruses that can cause respiratory infections. [ABSTRACT FROM AUTHOR]

Conventional routes for the production of formaldehyde rely on the use of methanol and air, with the presence of catalysts such as silver or mixed‐metal oxides. These processes are highly energy intensive and therefore raise concerns in terms of cost‐effectiveness and environmental impact. In that respect, sodium or sodium compounds are more favorable as catalysts for the direct dehydrogenation of methanol to water‐free formaldehyde. A method is presented for the coproduction of hydrogen and anhydrous formaldehyde – both valuable products – on the laboratory scale, with a particular focus on the design and testing of a sodium vapor catalyst dosing unit that enables the process to be performed continuously. [ABSTRACT FROM AUTHOR]

Iron silver oxide (AgxFe2−xO3; 0xFe2−xO3 shown in the figure can be indexed to the hexagonal structure of silver oxide and the rhombohedral structure of hematite and new X-ray Diffraction (XRD) peaks of AgxFe2−xO3 structure. The annealing and doping process seems to cause a serious change in the crystal structure of the thin film, it showed a serious change in its electrical properties. The electrical parameters of resistance for thin films were measured using the Hall measurement method at room temperature. With Hall measurements, the n-type carrier concentration of the Fe2O3 structure was calculated, and it was observed that its resistance was 1MΩ. Likewise, it was observed that AgxFe2−xO3 exhibited an n-type carrier concentration, and its resistance was calculated to be 0.5MΩ. The conductivity change is based on silver doping. The doping process seems to cause a change in the bandgap of the thin film, it showed a change in its optical properties. The film’s optical absorption was measured by UV–Vis photo spectroscopy. Subsequently, the structural and topographic properties of AgxFe2−xO3 structures were investigated by high-precision characterization devices. [ABSTRACT FROM AUTHOR]

A novel vapor–solid phase chemical conversion process is reported here to synthesise high-quality films of the conductive coordination polymer (c-CP) Ag5BHT (BHT = benzenehexanothiolate), which has the potential to be applied for the synthesis and processing of c-CP electronic devices. This approach involves reacting a silver oxide precursor and an H6BHT linker in an isopropanol solvent vapor atmosphere to obtain Ag5BHT thin films with controllable thickness (100–300 nm). The as-synthesized Ag5BHT thin films exhibit conductivities as high as 10 S cm−1. Additionally, under field-effect modulation, these nanofilms demonstrate remarkably high charge mobility (38 cm2 v−1 s−1). [ABSTRACT FROM AUTHOR]

[Display omitted] Plasmon-mediated chemical reaction (PMCR) is a highly attractive field of research. Here we report in situ surface-enhanced Raman spectroscopic (SERS) monitoring of plasmonic-mediated S S bond-forming reaction. The reaction is thought to be a self-coupling reaction proceeding by photoinduced aromatic S C bond arylation. Surprisingly, the S C arylation and S S coupling are found to be occurred on both partially oxidized silver and silver nanoparticles. The results demonstrated that silver oxide or hydroxide and small molecule donor sacrifice agent played a crucial role in the reaction. This work facilitates the in-situ manipulation and characterization of the active silver electrode interface in conjunction with electrochemistry, and also establishes a promising new guideline for surface plasmon resonance photocatalytic reactions on metal nanostructures with high efficiency. [ABSTRACT FROM AUTHOR]

We propose silver oxide as a cost‐effective and sustainable alternative to noble metals for the catalytic reduction of nitroaromatics. In the present investigation, we adopt a facile and green synthetic route for the synthesis of silver oxide nanostructures. The prepared nanostructures were found to crystallize in the cuprite phase and exhibit absorbance across the entire visible range of the electromagnetic spectrum. The catalytic potential of the silver oxide was evaluated by following the kinetics of nitrophenol reduction under ambient conditions and is observed to follow pseudo‐first order kinetics with the apparent rate constant kapp=4.24×10-3 ${{k}_{app}=4.24\ \times {10}^{-3}}$ s−1 at minimum concentration of the catalyst. We attribute the observed catalytic activity to the freshly generated catalytic surface featuring a partially reduced form of silver oxide during reaction. The findings highlight the efficacy of silver oxide in mitigating the environmental pollution originating from the recalcitrant nitroarenes. [ABSTRACT FROM AUTHOR]

(1) Background: Angiotensin-converting enzyme 2 (ACE2) is a crucial functional receptor of the SARS-CoV-2 virus. Although the scale of infections is no longer at pandemic levels, there are still fatal cases. The potential of the virus to infect the skin raises questions about new preventive measures. In the context of anti-SARS-CoV-2 applications, the interactions of antimicrobial nanomaterials (silver, Ag; diamond, D; graphene oxide, GO and their complexes) were examined to assess their ability to affect whether ACE2 binds with the virus. (2) Methods: ACE2 inhibition competitive tests and in vitro treatments of primary human adult epidermal keratinocytes (HEKa) and primary human adult dermal fibroblasts (HDFa) were performed to assess the blocking capacity of nanomaterials/nanocomplexes and their toxicity to cells. (3) Results: The nanocomplexes exerted a synergistic effect compared to individual nanomaterials. HEKa cells were more sensitive than HDFa cells to Ag treatments and high concentrations of GO. Cytotoxic effects were not observed with D. In the complexes, both carbonic nanomaterials had a soothing effect against Ag. (4) Conclusions: The Ag5D10 and Ag5GO10 nanocomplexes seem to be most effective and safe for skin applications to combat SARS-CoV-2 infection by blocking ACE2-S binding. These nanocomplexes should be evaluated through prolonged in vivo exposure. The expected low specificity enables wider applications. [ABSTRACT FROM AUTHOR]

Hybrid nanofluid models have the potential to significantly enhance heat transport in many applications, like coolant of electric devices, thermal energy storage, and heat exchangers. Therefore, the existing problem deals with the simulation of heat and mass transport due to the three-dimensional hybrid nanoliquid flow amid two gyrating disks containing silver Ag and titanium oxide TiO2 nanoparticles. Further, a magnetic field is employed normally to flow’s direction. Applications of Darcy–Forchheimer law are discussed in terms of the porous medium. The utilization of the Cattaneo–Christov model is considered for analyzing heat and mass transmission. Additionally, the influence of thermal radiation, non-uniform heat sink/source, and Brownian diffusivity are discussed in the flow analysis. The problem is designed on the basis of the higher-order nonlinear PDEs which are then converted to ODEs using appropriate variables. Using the numerical technique known as the shooting technique in MATLAB, the reduced mathematical structure is solved numerically. From this study, it is analyzed that the axial velocity profile is weakened near the upper disk but the axial velocity profile is amplified near the lower for upsurge in the magnetic factor and porosity parameter. Hybrid nanofluid concentration is lower for higher Schmidt numbers. [ABSTRACT FROM AUTHOR]

Billions of disposable thin‐film electronics will be produced annually in the near future, for applications in smart packaging, IoT, and wearable biomonitoring patches. For these cases, traditional rigid batteries are not optimal neither in terms of form and ergonomics nor ecological aspects. There is an urgent need for a new class of energy storage devices that are thin, stretchable, resilient, and recyclable. Herein, a novel architecture of materials and fabrication techniques is presented that permit a fully 3D printed soft‐matter thin‐film battery that is Resilient to mechanical strain, Repairable if cut, Rechargeable, and Recyclable at the end of its life. By taking advantage of a digitally printable ultra‐stretchable liquid metal‐based current collector and a novel Gallium‐Carbon anode electrode, the Ag2O‐Gallium battery is rapidly printed and customized per application. By optimizing the properties of the Gallium‐Carbon composite, a record‐breaking areal capacity of 26.37 mAh cm−2 is obtained, which improves after 10 cycles at 100% strain to 30.32 mAh cm−2, and an unprecedented maximum strain tolerance of ≈200%. Partially damaged batteries heal themselves. Severely damaged batteries are healed through innovative cold‐vapor stimulation. An example of a digitally printed, taylor‐made battery‐on‐the‐board health‐monitoring patch with printed sensors for monitoring the heart, and respiration is demonstrated. [ABSTRACT FROM AUTHOR]

Background: Silver nanoparticles are widely used in various fields such as industry, medicine, biotechnology, and agriculture. However, the inevitable release of these nanoparticles into the environment poses potential risks to ecosystems and may affect plant productivity. Coronatine is one of the newly identified compounds known for its beneficial influence on enhancing plant resilience against various stress factors. To evaluate the effectiveness of coronatine pretreatment in mitigating the stress induced by silver nanoparticles on cress plants, the present study was carried out. Results: Our findings indicated a decrease in multiple growth parameters, proline content, chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in cress plants exposed to silver nanoparticle treatment. This decline could be attributed to the oxidative stress induced by the presence of silver nanoparticles in the plants. Conversely, when coronatine treatment was applied, it effectively mitigated the reduction in growth parameters and pigments induced by the silver nanoparticles. Furthermore, we observed an increase in silver content in both the roots and shoot portions, along with elevated levels of malondialdehyde (MDA) content, hydrogen peroxide (H2O2), anthocyanins, glutathione (GSH), and antioxidant enzyme activities in plants exposed to silver nanoparticles. Concurrently, there was a decrease in total phenolic compounds, ascorbate, anthocyanins, and proline content. Pre-treatment of cress seeds with coronatine resulted in increased levels of GSH, total phenolic compounds, and proline content while reducing the silver content in both the root and shoot parts of the plant. Conclusions: Coronatine pre-treatment appeared to enhance both enzymatic and non-enzymatic antioxidant activities, thereby alleviating oxidative stress and improving the response to stress induced by silver nanoparticles. [ABSTRACT FROM AUTHOR]

Silver oxide (Ag2O) particles are wonderful candidates due to their unique properties, and their use in a wide range of research, industrial and biomedical applications is rapidly increasing. This makes it fundamental to develop simple, environmentally friendly methods with possible scaling. Herein, sodium borohydride and Datura innoxia leaf extract were applied as chemical and biological stabilizing and reducing agents to develop Ag2O particles. The primary aim was to evaluate the anticancer and antiviral activity of Ag2O particles prepared via two methods. XRD, UV-visible and SEM analyses were used to examine the crystallite structure, optical properties and morphology, respectively. The resulting green-synthesized Ag2O particles exhibited small size, spherically agglomerated shape, and high anticancer and antiviral activities compared to chemically synthesized Ag2O particles. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium-bromide) assay of green-synthesized Ag2O particles showed high anticancer activity against MCF-7 cells with IC50 = 17.908 µg/mL compared to chemically synthesized Ag2O particles with IC50 = 23.856 µg/mL. The antiviral activity of green-synthesized Ag2O particles and chemically synthesized Ag2O particles was also evaluated by a plaque-forming assay, and green-synthesized Ag2O particles showed higher antiviral ability with IC50 = 0.618 µg/mL as compared to chemically synthesized Ag2O particles with IC50 = 6.129 µg/mL. We propose the use of green-synthesized Ag2O particles in cancer treatment and drug delivery. [ABSTRACT FROM AUTHOR]

In this work, silver ferric oxide (AgFeO2) nanoparticles have been successfully synthesized using the co-precipitation method and characterized with various techniques. Highly porous, grain-like AgFeO2 nanoparticles were prepared. Furthermore, this work explores and for the first time proposes the possibility of using low-cost AgFeO2 nanoparticles with a delafossite structure for the low-temperature detection of nitrogen dioxide (NO2) gas. AgFeO2 nanoparticle powder was characterized using X-ray diffraction (XRD). It discloses the delafossite structure indicating the presence of both rhombohedral and hexagonal structures having an average crystallite size of 47 nm. The field emission scanning electron microscopy (FE-SEM) and energy-dispersive spectroscopy (EDS) study give the idea about dense distribution nanoparticles and confirm the elemental composition of AgFeO2, respectively. Transmission electron microscopy (TEM) shows that grain-like nanostructures have a particle size in the range of between 50 and 80 nm. The specific surface area was calculated by Brunauer–Emmett–Teller (BET), and it was found to be 31.9353 ± 0.1551 m2/g. It is found that the AgFeO2 gas sensor shows high selectivity to words NO2 gas at 8 ppm gas concentration at an operating temperature of 50 °C. [ABSTRACT FROM AUTHOR]

The immobilization of Aspergillus niger Lipase (E.C.3.1.1.3) via covalent binding on epoxy-activated chitosan-coated silver oxide nanoparticles (Ag2O/Chitosan) under optimized conditions was studied. Ultraviolet–visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectral analysis (XRD), Transmission electron microscopy (TEM), Field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-Ray Microanalysis (EDAX) were employed to characterize the size, structural composition, crystallinity, surface morphologies, & percentage elemental composition of prepared Ag2O NPs & Ag2O/Chitosan nanocomposites. Optimal immobilization conditions (coupling time (16 h), pH (7.8), activating agent concentration (4% v/v), enzyme concentration (0.6 mg/ml)) were evaluated to acquire maximum expressed activity of bound lipases. The optimum catalytic activity of immobilized & solubilized lipases was exhibited at pH 8.5, 60 °C, and pH 7.0, 45 °C respectively. Thermal stability of immobilized lipases (Ag2O/Chitosan-EPI@Lip) preserved 76.47% of catalytic activity at 60 °C after 2 h of incubation while solubilized lipases retained only 40.51% of catalytic activity under similar conditions. Kinetic parameters (Km, Vmax) of immobilized (39.69 µM, 21.32 µM/min) & native lipase (34.12 µM, 21.83 µM/min) were determined, demonstrating the enhanced efficacy of lipase after immobilization. Moreover, bound lipases exhibited remarkable reusability and storage stability. Thus, the present methodology suggests that (Ag2O/Chitosan-EPI@Lip) bioconjugate would be a potential biocatalyst for promoting sustainable productions & advanced technologies. [ABSTRACT FROM AUTHOR]

What does a famed literary theorist have to say about the interaction between 'literature' and 'philosophy'? Well, if he's Garrett Stewart, the celebrated agent of pyrotechnic style in the service of durable insights across disparate disciplines and media, then we have much reason to lean in and listen. Stewart is the author of 20 books that range with uncanny competency across Victorian narrative, contemporary American fiction, written auralities, poetics and prose stylistics, cinematic evolution from silver oxide to screen pixel, book art, scenes of reading in painting, and most recently, the vocal drama of Barbra Streisand. The distances between his disciplinary terrains are as vast as his close readings of them are coordinated and trenchant. Here, sitting down before a shared conversational canvas, Stewart fields questions from David LaRocca, who asks how he, if he, thinks about the program of literature and philosophy. LaRocca, editor of the recent Attention Spans: Garrett Stewart, a Reader (Bloomsbury, 2024) and the forthcoming Bandwidths: Reading Across Media with Garrett Stewart (Bloomsbury), tracks the urgency of our moment—in which literature and philosophy are independently besieged and yet may concede little rapprochement. Where does philosophy happen in literature (a philosopher's question) is turned around by Stewart such that we see literature conjuring philosophy at the level of the sentence. We are not peering 'in' so much as looking 'at' the art of literature teaching philosophy through refined reading and the analytical inquest of the syllable and the sayable. Anyone who works at the fraught fissure of these realms will benefit from the ways Stewart makes literature and philosophy sensible to one another—even as he productively unsettles the terms and conditions of their affiliation. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni is a major cause of global foodborne illnesses. To develop alternative antimicrobial strategies against C. jejuni, this study designed and optimized the green synthesis of metallic nanoparticles (NPs) with intracellular components of the medicinal fungus Ganoderma sessile to provide the needed reducing and stabilizing agents. NPs were characterized by transmission electron microscopy and dynamic light scattering, and the quasi-spherical NPs had sizes of 2.9 ± 0.9 nm for the copper oxide NPs and 14.7 ± 0.6 nm for the silver NPs. Surface charge assessment revealed zeta potentials of −21.0 ± 6.5 mV and −24.4 ± 7.9 mV for the copper oxide and silver NPs, respectively. The growth inhibition of C. jejuni by the NPs occurred through attachment to the outer cell membrane and subsequent intracellular internalization and resulted in minimum inhibitory concentrations of the silver NPs at 6 µg/mL and copper oxide NPs at 10 µg/mL. On the other hand, a differential ROS production caused by silver and copper NPs was observed. In summary, this research presents the first demonstration of using green synthesis with the medicinal fungus G. sessile to produce metallic NPs that effectively inhibit C. jejuni growth, providing a sustainable and effective approach to the traditional use of antimicrobials. [ABSTRACT FROM AUTHOR]

Abstract Background Silver nanoparticles are widely used in various fields such as industry, medicine, biotechnology, and agriculture. However, the inevitable release of these nanoparticles into the environment poses potential risks to ecosystems and may affect plant productivity. Coronatine is one of the newly identified compounds known for its beneficial influence on enhancing plant resilience against various stress factors. To evaluate the effectiveness of coronatine pretreatment in mitigating the stress induced by silver nanoparticles on cress plants, the present study was carried out. Results Our findings indicated a decrease in multiple growth parameters, proline content, chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids in cress plants exposed to silver nanoparticle treatment. This decline could be attributed to the oxidative stress induced by the presence of silver nanoparticles in the plants. Conversely, when coronatine treatment was applied, it effectively mitigated the reduction in growth parameters and pigments induced by the silver nanoparticles. Furthermore, we observed an increase in silver content in both the roots and shoot portions, along with elevated levels of malondialdehyde (MDA) content, hydrogen peroxide (H2O2), anthocyanins, glutathione (GSH), and antioxidant enzyme activities in plants exposed to silver nanoparticles. Concurrently, there was a decrease in total phenolic compounds, ascorbate, anthocyanins, and proline content. Pre-treatment of cress seeds with coronatine resulted in increased levels of GSH, total phenolic compounds, and proline content while reducing the silver content in both the root and shoot parts of the plant. Conclusions Coronatine pre-treatment appeared to enhance both enzymatic and non-enzymatic antioxidant activities, thereby alleviating oxidative stress and improving the response to stress induced by silver nanoparticles.

As a sooner or later risk, antimicrobial resistance due to the overuse of antibiotics is considered a nightmare facing humankind. The visible-light mineralization of antibiotic waste over nanoceramic photocatalysts is an innovative expectant method. Concerning this, nanostructured yttrium orthovanadate (YVO 4) is grown via an adapted sol-gel process tracked by loading of 1.0–4.0 wt% of silver oxide (Ag 2 O) to form heterojunction nanocomposite of Ag 2 O/YVO 4. The as-prepared heterostructures were applied for visible-light photoelimination of ciprofloxacin (CF) in water. The presence of Ag 2 O has enhanced both light absorbance and photogenerated carrier separation of YVO 4. The 3.0 to 4.0 wt% loading of Ag 2 O designated the thinnest bandgap of 2.4 eV regardless of the minor decrease in their specific surface areas from 220 in bare YVO 4 to 168 m2 g−1 for 3.0 % Ag 2 O/YVO 4. The complete mineralization of CF over 3.0 % Ag 2 O/YVO 4 was achieved after 60 min of light illumination at an optimized dose of 1.6 mg mL−1 and a reaction rate constant of 5.41 × 10−2 min−1. This improved photocatalyst has also a recyclable ability of ∼95 % of its initial photoactivity after the fifth experimental run. Therefore, the augmented light harvesting, surface texture, as well as superb carrier separation represent a key role in the performance of Ag 2 O/YVO 4. [ABSTRACT FROM AUTHOR]

This study aimed to develop a novel Gelatin silver oxide material for releasing nitric oxide bionanocomposite wound dressing with enhanced mechanical, chemical, and antibacterial properties for the treatment of diabetic wounds. The gelatin- silver oxide nanoparticles (Ag2O-NP) bio nanocomposite was prepared using chitosan and gelatin polymers incorporated with silver oxide nanoparticles through the freeze-drying method. The samples were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Results showed that the Ag2O-NP nanoparticles increased porosity, decreased pore size, and improved elastic modulus. The Ag2O-NP wound dressing exhibited the most effective antibacterial properties against Staphylococcus aureus and Escherichia coli. Among the samples, the wound dressing containing silver oxide nanoparticles demonstrated superior physical and mechanical properties, with 48% porosity, a tensile strength of 3.2 MPa, and an elastic modulus of 51.7 MPa. The fabricated wound dressings had a volume ratio of empty space to total volume ranging from 40% to 60%. In parallel, considering the complications of diabetes and its impact on the vascular system, another aspect of the research focused on developing a per2mediated wound dressing capable of releasing nitric oxide gas to regenerate damaged vessels and accelerate diabetic wound healing. Chitosan, a biocompatible and biodegradable polymer, was selected as the substrate for the wound dressing, and beta-glycerophosphate (GPβ), tripolyphosphate (TPP), and per2mediated alginate (AL) were used as crosslinkers. The chitosan-alginate (CS-AL) wound dressing exhibited optimal characteristics in terms of hole count and uniformity in the scanning electron microscope test. It also demonstrated superior water absorption (3854%) and minimal air permeability. Furthermore, the CS-AL sample exhibited an 80% degradation rate after 14 days, indicating its suitability as a wound dressing. The wound dressing was loaded with S-nitrosoglutathione (GSNO) powder, and the successful release of nitric oxide gas was confirmed through the grease test, showing a peak at a wavelength of 540 nm. Subsequent investigations revealed that the treatment of human umbilical vein endothelial cells (HUVECs) with high glucose led to a decrease in the expression of PER2 and SIRT1, while the expression of PER2 increased, which may subsequently enhance the expression of SIRT1 and promote cell proliferation activity. However, upon treatment of the cells with the modified materials, an increase in the expression of PER2 and SIRT1 was observed, resulting in a partial restoration of cell proliferative activity. This comprehensive study successfully developed per2-mediated bio-nanocomposite wound dressings with improved physical, mechanical, chemical, and antibacterial properties. The incorporation of silver oxide nanoparticles enhanced the antimicrobial activity, while the released nitric oxide gas from the dressing demonstrated the ability to mitigate vascular endothelial cell damage induced by high glucose levels. These advancements show promising potential for facilitating the healing process of diabetic wounds by addressing complications associated with diabetes and enhancing overall wound healing. [ABSTRACT FROM AUTHOR]

Background: Acinetobacter baumannii resistant strains lead to increased mortality, treatment costs, and an increase in the length of hospitalization. Nowadays, nanoparticles are considered a substitute for antibiotics. This study aimed to determine the MIC of Silver (Ag) and Zinc Oxide (ZnO) Nanoparticles (NPs) on Biofilm-Producing Acinetobacter baumannii and determine the relationship between MIC and frequency of efflux pump genes in cutaneous specimens in Shiraz, Southwest Iran in 2021–2022. Methods: In this study, specimens were collected from April 2021 to June 2022 at Namazi and Faqihi Hospitals in Shiraz. Investigation of biofilm production in multidrug resistance (MDR) isolates was done by the microtiter plate method. Synthesized nanoparticles were characterized by UV–vis spectrum, X-ray diffraction (XRD), and electron microscopy. The MIC of AgNPs and ZnONPs for isolates was done using the method described in the CLSI guideline (2018). The antibacterial effect of MIC of NPs on inanimate objects was done by colony counts. The prevalence of efflux pump genes (adeR, adeC, adeA, abeM, adeK, adeI) was also investigated by PCR technique. Results: The highest ceftriaxone resistance (68%) and lowest colistin resistance (7%) were identified. 57% of isolates were MDR. In addition, 71.9% could produce biofilm and 28.1% of isolates could not produce biofilm. The average size of AgNPs and ZnONPs in the present study is 48 and < 70 nm, respectively. The nanoparticles were spherical. The MIC and the MBC of the ZnONPs were in the range of 125 to 250 µg/mL respectively. Also, for AgNPs, the MIC and the MBC were in the range of 62.5 to 250 µg/ml, respectively. AbeM gene had the highest frequency and the AdeK gene had the lowest frequency. Statistical analysis showed that there is a relationship between the frequency of adeA, adeC, and adeM genes with the MIC of AgNPs and ZnONPs. Conclusion: According to the results of the present study, inanimate objects such as scalpels in contact with AgNPs (6000 µg/ml for 240 min) or ZnONPs (5000 µg/ml for 120 min) can be free of biofilm producing Acinetobacter baumannii with efflux pump genes. [ABSTRACT FROM AUTHOR]

Excessive reliance on fossil fuels causes a variety of difficulties and the use of efficient electrocatalysts material has exhibited significant attention for high electrocatalytic activity. Most transition metal oxide materials performance can be enhanced by the incorporation of metals for OER activity. This work presents the synthesis of samarium (Sm) doped silver niobium oxide (AgNbO 3) was achieved using sonication techniques. An electrocatalyst, Sm-doped AgNbO 3 , has shown promising results for oxygen evolution reaction (OER) in alkaline medium with a significant increase in active sites, enhanced electrical conductivity and improved stability. The Sm-doped AgNbO 3 electrocatalyst exhibits overpotential of 203 mV and Tafel slope of 35.22 mV dec−1 for OER activity at current densities of 10 mA cm−2. By utilizing, electrochemical surface area (ECSA), the Sm-doped AgNbO 3 electrocatalyst exhibited higher ECSA values of 1009 cm−2 with a higher roughness factor of 2008.60. Further, observations of low charge transfer resistance value (R ct = 0.17 Ω) along with a durability of 50 h, indicate that this material is highly efficient and long-lasting as an electrocatalyst for energy conversion systems. [Display omitted] • The sonication technique was employed to synthesized Sm-doped AgNbO 3 electrocatalyst. • BET confirmed larger catalytic surface area of Sm-doped AgNbO 3 electrocatalyst was responsible for higher catalytic efficiency for OER. • Electrocatalytic consequences show Sm-doped AgNbO 3 electrocatalyst exhibits the lower Tafel slope (35.22 mV dec−1) with overpotential 203 mV at current density of 10 mA cm−2. • Sm-doped AgNbO 3 electrocatalyst shows the higher stability for 50 h. • Sm-doped AgNbO 3 electrocatalyst exhibited conductive nature with lower value of R s (0.65 Ω) and R ct (0.17 Ω). [ABSTRACT FROM AUTHOR]

In presented communication, the hybrid nanomaterial (Ethylene Glycol + Ag + CuO) flow by a stretched cylinder is numerically analyzed. Thermal characteristics are explored by thermal radiation and Newtonian heating. Flow analysis is performed via consideration of slip boundary and stagnation-point. Heat transport and flow expressions (PDEs) are converted into ODEs. In order to employ bvp4c (shooting method), the resulting ODEs are then reduced into first-order system of ODEs. Flow, heat transport rate, temperature and surface friction coefficient are examined graphically under influences of involved sundry parameters. Comparison is made among hybrid nanofluid (Ethylene Glycol + Ag + CuO), nanofluid (Ethylene Glycol + Ag) and basefluid (Ethylene Glycol) for physical quantities of interest. Velocity shows increasing behavior towards the higher value of nanoparticles volume fraction for silver and copper oxide, curvature, velocity ratio and velocity slip parameters. Higher estimations of nanoparticles volume fraction for silver and copper oxide, curvature, radiation and conjugate parameters cause intensification in fluid temperature. Skin friction is controlled against a higher velocity ratio parameter. Nusselt number decays with an increment in velocity ratio parameter while it boosts via higher nanoparticles volume fraction for silver and copper oxide and curvature parameter. Best performance is noticed for hybrid nanomaterial. [ABSTRACT FROM AUTHOR]

This article describes benefits of the application of zinc oxide submicron particles (ZnO SMPs), zinc oxide nanoparticles (ZnO NPs) and ZnO NPs combined with silver NPs (ZnO + Ag NPs) in chrysanthemum micropropagation. Single node explants of Chrysanthemum × morifolium (Ramat.) Hemsl. 'UTP Burgundy Gold (UBG)' and 'UTP Pinky Gold (UPG)' were inoculated on the Murashige and Skoog (MS) medium and treated with 100 mg · L−1, 200 mg · L−1, or 400 mg · L−1 ZnO SMPs, ZnO NPs (1.5% H2O), ZnO NPs (6% H2O), ZnO + 0.1% Ag NPs (1.5% H2O), ZnO + 0.1% Ag NPs (6% H2O), ZnO + 1% Ag NPs (1.5% H2O) and ZnO + 1% Ag NPs (6% H2O). Generally, the tested materials stimulated the growth and development of plantlets. In 'UBG', the most prominent treatments affecting increases in the number of leaves, micropropagation coefficient, shoot length and shoot FW/DW weight included 400 mg · L−1 ZnO SMPs and 100 mg · L−1 ZnO NPs (6% H2O). In 'UPG', the treatments with 200 mg · L−1 ZnO + 0.1% Ag NPs (6% H2O) and 200 mg · L−1 ZnO + 1% Ag NPs (6% H2O) were the most successful. The latter treatment stimulated an intensive development of root systems in the two studied cultivars. High values of leaf area, perimeter and width were reported in both cultivars for 400 mg · L−1 ZnO + 1% Ag NPs (6% H2O). As compared to the control, the treated plants were characterised by a similar or, most often, lower content of chlorophylls and carotenoids. The randomly amplified polymorphic DNA (RAPD) and start codon targeted polymorphism (SCoT) marker system analyses of the 400 mg · L−1 ZnO SMPs/ZnO NPs/ZnO + Ag NPs-treated chrysanthemums confirmed their genetic fidelity with the control plants. The obtained results can be implemented in the commercial large-scale production of chrysanthemums. [ABSTRACT FROM AUTHOR]

Silver(I) oxide is considered as one of the promising materials for photoelectrochemical technologies because it has an optimal band gap, relatively low cost, and a wide variety of production methods. However, its characteristics such as quantum efficiency, morphology, and crystal structure parameters require optimization, which can be achieved by applying the most suitable method for the obtaining of the material. One of the fairly simple methods is the anodic oxidation of silver or its alloys in alkaline media, which allows obtaining oxide phases with a controlled composition and predictable properties by varying the concentration of the alloy components and electrolysis mode. The purpose of this work is to reveal the features of anodic formation and to determine the photoelectrochemical characteristics of silver(I) oxide on silver–palladium alloys in deaerated 0.1 M KOH solution. The regularities of the anodic formation of Ag(I) oxide on alloys of the Ag–Pd-system with the palladium atomic fraction from 0.05 to 0.20 in deaerated 0.1 M KOH solution were studied by non-stationary electrochemical methods of cyclic voltammetry, chronoamperometry with synchronous recording of photocurrent, and photopotential measurements. The phase composition of the alloys (alpha phase) was determined from the results of X-ray diffractometry. Chemical composition was determined by energy dispersive microanalysis. Photoelectrochemical parameters were calculated from the results of the photocurrent and photopotential measurements. It was established that the Ag(I) oxide anodically formed on silver–palladium alloys is characterized by n-type conductivity and the predominance of donor defects. On the alloys with a relatively low palladium concentration (5 and 10 at %), Ag(I) oxide with a higher concentration of defects is formed, while on alloys with a relatively high palladium concentration (15 and 20 at %), with a lower concentration of defects than on pure silver. [ABSTRACT FROM AUTHOR]

In this research, the explosive wire method is used to prepare silver nanoparticles and study their effect on two types of bacteria, E. coli and Staphylococcus aureus. The X-ray diffraction pattern of silver nanoparticles after deposition on glass pieces shows a peak of silver and silver oxide. The FE-SEM morphology of silver oxide particles shows small spherical-like clusters of irregular flower-shaped particles. Meanwhile, the AFM analysis of the silver nanoparticles shows that the average roughness of the aggregates is 57 nm and the average size of the nanoparticles is 20.92 nm. The study of the effect of silver nanoparticles on two types of bacteria, namely E. coli and Staphylococcus aureus, has shown that these nanoparticles have achieved a killing rate of 99% for both types of bacteria. [ABSTRACT FROM AUTHOR]

Organic pollutant detection has caused widespread concern regarding due to their potential environmental and human health risks. In this work, a nitrogen-doped titanium dioxide/silver oxide (N-TiO2/Ag2O) composite has been designed as a sensitive photoelectrochemical (PEC) monitoring platform of organic dyes. Sensitive determination relies on the outstanding PEC performance of N-TiO2/Ag2O. The improved PEC performance stems from the effective separation of photocarriers and the extended light response range provided by the narrowing bandgap and a p–n junction with N-TiO2/Ag2O. The N-TiO2/Ag2O electrode exhibits a photocurrent density of up to 2.2 mA/cm2, demonstrating three times increase compared with the photocurrent density observed with the pure TiO2 film. The linear detection range for rhodamine B (RhB), methylene blue (MB), and methyl orange (MO) is 0.2 ng/mL to 10 μg/mL with an ultrasensitive detection limit of 0.2 ng/mL without bias voltage. Due to the outstanding photocurrent density and sensitive response to organic pollutants, the N-TiO2/Ag2O PEC sensor provided a promising analytical method to detect environmental organic dyes. [ABSTRACT FROM AUTHOR]

The integration of nanoparticles (NPs) holds promising potential to bring substantial advancements to plant cryopreservation, a crucial technique in biodiversity conservation. To date, little attention has been focused on using nanoparticles in cryobiology research. This study aimed to assess the effectiveness of NPs in enhancing the efficiency of plant cryopreservation. In-vitro-derived shoot tips of bleeding heart (Lamprocapnos spectabilis (L.) Fukuhara) 'Gold Heart' and 'Valentine' were used as the plant material. The encapsulation-vitrification cryopreservation protocol included preculture, encapsulation, dehydration, storage in liquid nitrogen, rewarming, and recovery steps. Gold (AuNPs), silver (AgNPs), or zinc oxide (ZnONPs) nanoparticles were added at various concentrations either into the preculture medium or the protective bead matrix during encapsulation. The explant survival and further morphogenic and biochemical events were studied. Results showed that the impact of NPs on cryopreservation outcomes was cultivar-specific. In the 'Valentine' cultivar, incorporating 5 ppm AgNPs within the alginate bead matrix significantly improved cryopreservation efficiency by up to 12%. On the other hand, the 'Gold Heart' cultivar benefited from alginate supplementation with 5 ppm AgNPs and 5–15 ppm ZnONPs, leading to an over 28% increase in the survival rate of shoot tips. Interestingly, adding NPs to the preculture medium was less effective and sometimes counterproductive, despite promoting greater shoot proliferation and elongation in 'Valentine' explants compared to the control. Moreover, nanoparticles often induced oxidative stress (and enhanced the activity of APX, GPOX, and SOD enzymes), which in turn affected the biosynthesis of plant primary and secondary metabolites. It was found that supplementation of preculture medium with higher concentration (15 ppm) of gold, silver and zinc oxide nanoparticles stimulated the production of plant pigments, but in a cultivar-dependent matter. Our study confirmed the beneficial action of nanoparticles during cryopreservation of plant tissues. [ABSTRACT FROM AUTHOR]

The current research aimed to study the green synthesis of silver oxide nanoparticles (AgONPs) using Rhynchosia capitata (RC) aqueous extract as a potent reducing and stabilizing agent. The obtained RC-AgONPs were characterized using UV, FT-IR, XRD, DLS, SEM, and EDX to investigate the morphology, size, and elemental composition. The size of the RC-AgONPs was found to be ~ 21.66 nm and an almost uniform distribution was executed by XRD analysis. In vitro studies were performed to reveal biological potential. The AgONPs exhibited efficient DPPH free radical scavenging potential (71.3%), reducing power (63.8 ± 1.77%), and total antioxidant capacity (88.5 ± 4.8%) to estimate their antioxidative power. Antibacterial and antifungal potentials were evaluated using the disc diffusion method against various bacterial and fungal strains, and the zones of inhibition (ZOI) were determined. A brine shrimp cytotoxicity assay was conducted to measure the cytotoxicity potential (LC50: 2.26 μg/mL). In addition, biocompatibility tests were performed to evaluate the biocompatible nature of RC-AgONPs using red blood cells, HEK, and VERO cell lines (< 200 μg/mL). An alpha-amylase inhibition assay was carried out with 67.6% inhibition. Moreover, In vitro, anticancer activity was performed against Hep-2 liver cancer cell lines, and an LC50 value of 45.94 μg/mL was achieved. Overall, the present study has demonstrated that the utilization of R. capitata extract for the biosynthesis of AgONPs offers a cost-effective, eco-friendly, and forthright alternative to traditional approaches for silver nanoparticle synthesis. The RC-AgONPs obtained exhibited significant bioactive properties, positioning them as promising candidates for diverse applications in the spheres of medicine and beyond. [ABSTRACT FROM AUTHOR]

This study presents a green, novel, one-pot, and single-step method for synthesizing reduced graphene oxide/silver nanocomposites (RGO/Ags) with different Ag ratios using Roselle extract and 80kGy of γ-ray for symmetric supercapacitor applications. As a natural antioxidant, Roselle extract served as a scavenger of oxidative free radicals to inhibit the oxidation of graphene oxide/silver nitrate suspensions (GO/AgO3), which were undergoing radiolysis under γ irradiation. An additional sample of GO/AgO3 was irradiated with the same dose in the absence of Roselle for comparability. The efficient reduction of GO/AgO3 has been assessed by several analytical techniques, including XRD, FTIR, TEM, and Raman spectroscopy. The presence of Roselle hindered the formation of the AgO phase while concurrently promoting the construction of the Ag phase. Furthermore, using Roselle extract results in a more homogeneous dispersion of spherical silver nanoparticles on reduced graphene oxide (RGO) sheets. Symmetric supercapacitor has been assembled from arbitrary samples amongst RGO/Ags, which showed good performance like low internal resistance and suitable specific capacitance (96 F/g at current density 0.2 A/g). The findings point to the merit of RGO/Ag nanocomposites prepared by the synergetic effect of γ-ray and Roselle extract as an efficient supercapacitor material. [ABSTRACT FROM AUTHOR]

The paper breaks the general concepts and shows that pore formation is possible in anodic aluminum barrier oxide by anodizing of pure Al, and also presents the results of electrochemical anodizing in boric acid and citrate buffer aqueous solutions of homogeneous binary alloys AlCu (4 wt.%), AlZn (3 wt.%) and AlAg (5.2 wt.% and 16.2 wt.%). Barrier anodizing allowed obtaining Al2O3 thin films doped with copper, zinc and silver. The anodizing behavior and the effect of anodic current density on the charge were studied, and scanning electron microscopy, X-ray photoelectron spectroscopy and Auger electron spectroscopy analyses were performed. The doped alumina thin films, which are a mixture of Al2O3, Cu2O, ZnO, Ag2O, AgO and promising double metal oxides CuAlO2, AgAlO2 and ZnAl2O4, are promising for use as resistive switching, photoelectron, mechanical, photo-thermoelectric and fluorescence materials; sensors; and transparent conductive and photocatalyst films. [ABSTRACT FROM AUTHOR]

In the context of advancing flexible electronic technologies, conductive ink has garnered significant scholarly interest. Wherein, metal-organic decomposition (MOD) ink composed of silver precursors, complexing agents, and volatile organic solvents, has been widely studied due to its advantages such as simple preparation, long shelf life, high jetting stability, and low-temperature processing. However, the volumetric reduction of MOD ink frequently surpasses 80%, which typically could lead to multiple voids and breaks in the conductive film, resulting in poor conductivity. Meanwhile, a high temperature of above 180 °C is usually required for the MOD ink to be converted into conductive film. Nevertheless, it is imperative for the ink to be deposited onto substrates at low temperatures. Herein, a low temperature conducting ink with multiple silver source precursors has been developed. The results show that after sintering at 100 °C for 40 min on a polyimide (PI) substrate, the resistivity of the silver film was 16.8 µ Ω cm, which is only ten times higher than that of bulk silver, and the silver film with good uniformity and conductivity can be formed. Defects, such as voids and cracks, are significantly reduced through the gradient decomposition of different silver source during the sintering process. The formula of ink and the effects of sintering temperature on the microstructure and electrical properties of silver ink thin films have been studied in details using XRD, SEM, EDX, and four-probe techniques. [ABSTRACT FROM AUTHOR]

The extracted ash from common water reeds locally available in Iraq was used as a cost-effective silica source for single-step synthesis of a heterojunction photocatalyst (Ag2O@CRA) combining 9.75 % Ag2O and a surface area of 99.849 m2/g. The Ag2O@CRA photocatalyst was used to investigate methylene blue (MB) degradation which was eliminated at an initial MB concentration of 20 mg/L, Ag2O@CRA dose of 0.1g/100 mL, pH of 7 after 60 min at visible light. This photocatalyst displayed excellent stability after five cycles with more than 91 % removal of MB dye. The ⦁OH was the main radical involved in the MB degradation.

AbstractIn this work, we studied the effect of silver nanoparticles on the IR absorption mechanism in Ag/Ag2O composites. Ag/Ag2O composites were prepared by exposing silver films prepared by thermal evaporation to oxygen plasma afterglow. The infrared spectra of these samples were analysed. The results obtained showed that, the individual silver nanoparticles affect the vibrations of chemical bonds in Ag/Ag2O composites, and this is inferred from the gradual decrease in intensity when moving towards lower wavenumbers. In addition, it was found that the effect of individual silver nanoparticles is greatest in the frequency range of Ag–O bond vibrations and becomes weaker in the case of bonds with higher vibration energies.

Vat polymerization technology allows filler particles to be incorporated into photosensitive 3D printing resin to improve the properties of the printed material. This method can be used to produce medical devices with an antimicrobial effect that can reduce biofilm formation and reduce infections due to indwelling devices. Metal oxides have the potential to combat antibiotic‐resistant bacteria, further lowering the risk of hospital‐acquired infections. The antimicrobial agent in this study, silver oxide, was evaluated for its antimicrobial effect against gram‐positive bacteria (Staphylococcus epidermidis) as these are the main cause of biofilm formation. The 3D printed samples demonstrated a strong antimicrobial effect at low concentrations of 1 wt.%. Two vat polymerization technologies, stereolithography (SLA) and digital light processing (DLP), were compared for their suitability for producing 3D printed samples with an antimicrobial effect. DLP successfully produced samples with mechanical properties comparable to the base resin, whereas SLA samples had reduced mechanical strength at higher concentrations of silver oxide filler. Neither printing technology nor silver oxide concentration had a statistically significant effect on the mechanical properties of the printed materials. [ABSTRACT FROM AUTHOR]

Anhydrous dimolybdenum perfluorotetrabenzoate Мо2(ООСС6F5)4 (I) and silver perfluorocyclohexanoate AgOOCC6F11 (II) are synthesized for the first time. Complex I is synthesized by the transcarboxylation of dimolybdenum tetraacetate with pentafluorobenzoic acid. Compound II is synthesized from freshly prepared silver oxide and perfluorocyclohexanoic acid. The evaporation of the complexes is studied by the Knudsen method with mass spectral analysis of the gas phase. The sublimation of Мо2(ООСС6F5)4 is congruent. The enthalpy of sublimation and the equation of the temperature dependence of the vapor pressure are found. The evaporation of AgOOCC6F11 is accompanied by the complete thermal decomposition with the formation of Ag(s) and mainly С6F12, С6F10, and CO2 molecules. The standard enthalpies of thermal decomposition ( (5) = 439.5 ± 16.4 kJ/mol, (6) = 325.2 ± 14.0 kJ/mol) and formation of the silver complex ( (AgOOCC6F11, c) = –2751.0 ± 24.4 kJ/mol) are determined. [ABSTRACT FROM AUTHOR]

This paper addresses the polymer conductive paste formulation based on modified silver oxide (Ag2O) particles. This paste is distinguished by the self-reduction of Ag2O particles to conductive Ag through a thermal process. It is suitable for the fabrication of conductive flexible structures. In addition to detailing the paste's recipe, the paper provides a comparison and assesses the effect of modifying Ag2O particles through 5 hours of milling, comparing them with large-grain particles in their original state, focusing on screen printing technology. The investigation delves into the impact of milling on particle size and distribution using as well as to verify the purity of the homogeneously created powder. Samples are manufactured using an Ag2O -based paste, screen-printed on a flexible PET Mylar® A substrate, 50 µm thick. The printed patterns are cured at 120°C to 160°C for 10 minutes while monitoring the effect of vacuum and number of printed layers on sheet resistance. Sheet resistance measurements are conducted using a 4-point probe test method. The results suggest that wet planetary ball milling is a suitable technique for modifying Ag2O particles, rendering them suitable to produce polymer conductive paste. In addition, milling produces only silver oxide fine powder particles, according to XRD patterns. [ABSTRACT FROM AUTHOR]

In this study, Nanocomposites (NCs) of silver oxide (Ag2O) and Titanium dioxide (TiO2) of various combinations Ag2O/TiO2 (5 mM: 1 mM), Ag2O/TiO2 (1 mM: 5 mM) and Ag2O/TiO2 (1 mM: 1 mM) were prepared by the microemulsion method. Batch adsorption experiments were conducted to evaluate the adsorption of hazardous dyes such as crystal violet (CV), methyl orange (MO), and methylene blue (MB) in various combinations. The selective adsorption of dyes under the influence of both concentration and temperature was monitored and observed that up to 90–93% of CV, MO, and MB were removed, when the maximum concentrations of CV: MO: MB were (10: 10: 50), (10: 50: 10) and (50: 10: 10) respectively. The adsorption data were fitted to Langmuir, Freundlich and Temkin isotherms, however, based on R2 value, Freundlich model was found suitable indicating that maximum adsorption of dyes was taken place at lower temperature which exhibited the exothermic nature of the process. Prior to the sorption study, the prepared nanostructures were characterized by X-ray diffraction (XRD), Zeta potential, Fourier transforms infrared (FTIR) spectroscopy, UV–Visible spectroscopy, field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS). The diffraction patterns confirmed the structural formation of Nanocomposites and the average crystallite sizes for Ag2O/TiO2 (5 mM: 1 mM), Ag2O/TiO2 (1 mM: 5 mM) and Ag2O/TiO2 (1 mM: 1 mM) were calculated to be 23, 27, and 50 nm respectively. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) are metal oxide nanomaterials, which are important for several applications: antibacterial, anthelmintic, antiprotozoal and antitumoral, among others. These applications are mainly related to the ability to spontaneously produce and induce the production of reactive oxygen species that are important components for the destruction of pathogens and tumor cells. While trying to potentiate ZnO NPs, studies have associated these NPs with silver oxide (AgO) or silver (Ag) NPs. It has already been reported that this combination (Ag-ZnO/AgO NPs) is able to enhance the microbicidal potential. Although possessing much potential for several purposes, it is important to evaluate whether this association also poses the risk of toxicity to cells and experimental models. Therefore, this work aimed to evaluate the toxicity of various Ag-ZnO/AgO NP nanocomposites, in vitro and in vivo. Accordingly, ZnO nanocrystals and nanocomposites with various concentrations of AgO (ZnO:5Ag, ZnO:9Ag or ZnO:11Ag) were used in different cytotoxicity models: Galleria mellonella (G. mellonella), cell lines (VERO and RAW 264.7) and C57BL/6 mice. In the G. mellonella model, four concentrations were used in a single dose, with subsequent evaluation of mortality. In the case of cells, serial concentrations starting at 125 µg/mL were used, with subsequent cytotoxicity assessment. Based on the safe doses obtained in G. mellonella and cell models, the best doses were used in mice, with subsequent evaluations of weight, biochemistry as also renal and liver histopathology. It was observed that the toxicity, although low, of the nanocomposites was dependent upon the concentration of AgO used in association with ZnO NPs, both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

The objective of this research was to develop a surface modification for the NiTi shape memory alloy, thereby enabling its long-term application in implant medicine. This was achieved through the creation of innovative multifunctional hybrid layers comprising a nanometric molecular system of silver-rutile (Ag-TiO2), known for its antibacterial properties, in conjunction with bioactive submicro- and nanosized hydroxyapatite (HAp). The multifunctional, continuous, crack-free coatings were produced using the electrophoretic deposition method (EPD) at 20 V/1 min. Structural and morphological analyses through Raman spectrometry and scanning electron microscopy (SEM) provided comprehensive insights into the obtained coating. The silver within the layer existed in the form of nanometric silver carbonates (Ag2CO3) and metallic nanosilver. Based on DTA/TG results, dilatometric measurements, and high-temperature microscopy, the heat treatment temperature for the deposited layers was set at 800 °C for 2 h. The procedures applied resulted in the creation of a new generation of materials with a distinct structure compared with the initial nanopowders. The resulting composite layer, measuring 2 μm in thickness, comprised hydroxyapatite (HAp), apatite carbonate (CHAp), metallic silver, silver oxides, Ag@C, and rutile exhibiting a defective structure. This structural characteristic contributes significantly to its heightened activity, influencing both bioactivity and biocompatibility properties. [ABSTRACT FROM AUTHOR]

Propionibacterium acnes plays a critical role in the development of acne vulgaris. There has been a rise in the number of patients carrying P. acnes strains that are resistant to antibiotics. Thus, alternative anti-microbial agents are required. Zinc oxide (ZnO-NPs) and silver (Ag-NPs) nanoparticles can be used against several antibiotic-resistant bacteria. The impact of Ag-NPs and ZnO-NPs against two clinical strains of P. acnes, P1 and P2, and a reference strain, NCTC747, were investigated in this research. A chemical approach for the green synthesis of Ag-NPs and ZnO-NPs from Peganum harmala was employed. The microtiter plate method was used to examine the effects of NPs on bacterial growth, biofilm development, and biofilm eradication. A broth microdilution process was performed in order to determine minimal inhibitory (MIC) concentrations. Ag-NPs and ZnO-NPs had a spherical shape and average dimensions of 10 and 50 nm, respectively. MIC values for all P. acnes strains for Ag-NPs and ZnO-NPs were 125 µg/mL and 250 µg/mL, respectively. Ag-NP and ZnO-NP concentrations of 3.9- 62.5 µg/mL and 15–62.5 µg/mL significantly inhibited the growth and biofilm formation of all P. acnes strains, respectively. ZnO-NP concentrations of 15–62.5 μg/mL significantly inhibited the growth of NCTC747 and P2 strains. The growth of P1 was impacted by concentrations of 31.25 μg/mL and 62.5 μg/mL. Biofilm formation in the NCTC747 strain was diminished by a ZnO-NP concentration of 15 μg/mL. The clinical strains of P. acnes were only affected by ZnO-NP titres of more than 31.25 μg/mL. Established P. acne biofilm biomass was significantly reduced in all strains at a Ag-NP and ZnO-NP concentration of 62.5 µg/mL. The findings demonstrated that Ag-NPs and ZnO-NPs exert an anti-bacterial effect against P. acnes. Further research is required to determine their potential utility as a treatment option for acne. [ABSTRACT FROM AUTHOR]

Simple Summary: The increasing presence or contamination of various everyday-life products (including foodstuffs) by graphene oxides and silver nanoparticles (GOs and AgNPs, respectively) raises a risk of their possibly deleterious effects on digestive functions and, consequently, nutrient and energy intake by an organism. The study addresses this issue by considering various NP concentrations and exposure times. The scarcity of relevant data makes such studies necessary for the reliable assessment of NP effects. This study on a model insect species—adult house crickets—revealed a changed profile of digestive enzymes' activities in the gut, mainly when a high content of NPs was present in the food: stimulated digestion of carbohydrates and lipids but inhibited digestion of proteins. These changes were more pronounced in AgNP-treated than in GO-treated insects and increased with exposure time. Disturbed digestion led to decreased food consumption with exposure time in AgNP-treated crickets. Food assimilation was also affected—the cumulative food assimilation (CFA) was higher and lower compared with the control in crickets exposed to the lowest and moderate concentrations of AgNPs, respectively. These findings confirmed weak or no effects of low amounts of NPs in food and revealed that their higher concentrations may adversely influence digestive processes and resulting nutrient and energy intakes, particularly during prolonged exposure of an organism. The advancement of nanotechnology poses a real risk of insect exposure to nanoparticles (NPs) that can enter the digestive system through contaminated food or nanopesticides. This study examines whether the exposure of model insect species—Acheta domesticus—to increasing graphene oxide (GO) and silver nanoparticle (AgNP) concentrations (2, 20, and 200 ppm and 4, 40, and 400 ppm, respectively) could change its digestive functions: enzymes' activities, food consumption, and assimilation. We noticed more pronounced alterations following exposure to AgNPs than to GO. They included increased activity of α-amylase, α-glucosidase, and lipase but inhibited protease activity. Prolonged exposure to higher concentrations of AgNPs resulted in a significantly decreased food consumption and changed assimilation compared with the control in adult crickets. A increase in body weight was observed in the insects from the Ag4 group and a decrease in body weight or no effects were observed in crickets from the Ag40 and Ag400 groups (i.e., 4, 40, or 400 ppm of AgNPs, respectively), suggesting that even a moderate disturbance in nutrient and energy availability may affect the body weight of an organism and its overall condition. This study underscores the intricate interplay between NPs and digestive enzymes, emphasizing the need for further investigation to comprehend the underlying mechanisms and consequences of these interactions. [ABSTRACT FROM AUTHOR]

Background: Metallic nano-oxide has been influenced the environment in the past two decades. Their consequences are dreadfully uncertain. The increased graph of their interference suggested many extensive studies in various fields of the environment. The Gossypium hirsutum one of the prime harvest plants in India has been chosen for studying the impacts of metallic nano-oxide on their morphological characters as well as their fresh shoot and root weights. Methods: Study has been done in July 2020 as a randomized triplet. The need for the study was fulfilled by the four different metallic nano-oxides with their five specific concentrations. The metallic nano-oxides were titanium oxide, silver oxide, copper oxide and zinc oxide. The five concentrations 00 ppm, 40 ppm, 60 ppm, 80 ppm and 100 ppm were taken from each one of metallic nano-oxide. Result: The zinc oxides treatment gave noteworthy positive growth and development in Gossypium hirsutum from germination to the blossoming time. Conversely, the concentrations of silver oxides were found little toxic for the growth of species. The copper and titanium oxides indicated little diversity in their growth patterns. The germination studies calculated best with titanium oxide treatment. The 80 ppm concentration of copper oxide also reported better results at germination in comparison to control. [ABSTRACT FROM AUTHOR]

The evolution of parasite resistance to antiparasitic agents has become a serious health issue indicating a critical and pressing need to develop new therapeutics that can conquer drug resistance. Nanoparticles are novel, promising emerging drug carriers that have demonstrated efficiency in treating many parasitic diseases. Lately, attention has been drawn to a broad-spectrum nanoparticle capable of converting absorbed light into heat via the photothermal effect phenomenon. The present study is the first to assess the effect of silver nanoparticles (Ag NPs) and iron oxide nanoparticles (Fe3O4 NPs) as sole agents and with the combined action of the light-emitting diode (LED) on Blastocystis hominins (B. hominis) in vitro. Initially, the aqueous synthesized nanoparticles were characterized by UV-Vis spectroscopy, zeta potential, and transmission electron microscopy (TEM). The anti-blastocyst efficiency of these NPs was tested separately in dark conditions. As these NPs have a wide absorption spectrum in the visible regions, they were also excited by a continuous wave LED of wavelength band (400–700 nm) to test the photothermal effect. The sensitivity of B. hominis cysts was evaluated using scanning laser confocal microscopy whereas the live and dead cells were accurately segmented based on superpixels and the k-mean clustering algorithm. Our findings showed that this excitation led to hyperthermia that induced a significant reduction in the number of cysts treated with photothermally active NPs. The results of this study elucidate the potential role of photothermally active NPs as an effective anti-blastocystis agent. By using this approach, new therapeutic antiparasitic agents can be developed. [ABSTRACT FROM AUTHOR]

Among the different available methods, hydrogen production by electrocatalytic water splitting is the most attractive method. Here, Ag 2 O/NiO hybrid nanostructures with different molar ratios of silver and nickel ions were synthesized by co-precipitation method. Nickel oxide and silver oxide nanostructures was also prepared to compare with Ag 2 O/NiO nanocomposites. Investigations indicated that the as-prepared Ag 2 O/NiO nanocomposite with an equal molar ratio of metal ions shows high water splitting activity in 1 M KOH solution and only 430 and 140 mV are needed as overpotentials under a current density of 10 mA cm−2 for oxygen and hydrogen evolution reactions (OER and HER), respectively. Ag 2 O/NiO has the largest electrochemically active surface area, the lowest Tafel slope, the smallest semicircle diameter in the Nyquist plots, and the lowest charge transfer resistance for both OER and HER among all tested nanomaterials. Furthermore, Ag 2 O/NiO showed excellent stability for OER and HER for at least 30 h. [Display omitted] • Ag2O/NiO hybrid nanostructures were synthesized by co-precipitation method. • The Ag2O/NiO (0.5:0.5) nanocomposite showed high activity and durability for OER and HER. • The overpotential for HER and OER was 140 and 430 mV under constant j of 10 mA cm-2. • This nanocomposite showed excellent stability for OER and HER for at least 30 h. [ABSTRACT FROM AUTHOR]

The present work shows the synthesis of Ag nanoparticles in a two-phase system (organic/aqueous), in which the amphiphilic properties of naphthenic acid are used for the formation of reverse micelles that act as micro reactors. Therefore, the appropriate energy conditions are given for the precipitation of metallic Ag nanoparticles, using AgNO3 as a precursor. Likewise, the effect of the synthesis reaction time was studied to know its relationship with the final morphology of the material. X-Ray Diffraction and Scanning Electron Microscopy, coupled with Energy Dispersive Spectroscopy, were used to characterize the solids. The results show that in the Ag+-Ag° reduction reaction carried out at t = 1.5 h and T = 200 °C, metallic silver nanoparticles precipitate of FCC structure, with homogeneous globular morphology and average diameter of 50 nm. By prolonging the residence time of the system at 200 °C (artificial aging), the material undergoes a series of transformations both in size and morphology, causing partial oxidation of the silver. At TEA of 0.5 h, the particles grow without evident structural change; by increasing TEA to 1 h, the transformation in solid state is observed, obtaining a mixture of phases, AgO, Ag3O4 and Ag2O, coming from the partial oxidation of silver, with monoclinic and hexagonal structures and the dimensions nano and micrometric. Finally, increasing the aging time to 1.5 h only causes an increase in particle size, without modification in the structures obtained at shorter times. [ABSTRACT FROM AUTHOR]

Objective(s): Cognizant of the harsh chemical method of nanoparticles synthesis, researchers are shifting towards the green phyto-mediated synthetic approaches. We herein report the green synthesis of Ag NPs and Co3O4 NPs using silver nitrate solution and cobalt nitrate solution as precursors added to aqueous extract of Croton Macrostachyus leaf extract to evaluate their antibacterial activity. Materials and Methods: The Characterization of the biosynthesized NPs were carried out by using spectroscopic techniques as X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), and scanning electron microscopy (SEM). Results: The average crystallite size of Ag NPs was found to be 12.62 nm from the XRD data, indicating a cubic crystal structure whereas that of Co3O4 NPs was found to be 12.75 nm, indicating a cubic spinel crystal structure. The energy band gap for Ag NPs and Co3O4 NPs were 3.38 eV, and 3.34 eV respectively. The SEM images showed non-homogeneity of particles distribution with irregular geometries attributable to their shape and size for Ag NPs whereas spherical as well as irregular geometries attributed to non-homogeneity of the particles for Co3O4 NPs. The FTIR identifies the functional groups of the bioactive molecules that were actively involved as stabilizing and capping agents to prevent agglomeration of Ag NPs and Co3O4 NPs. The agar-well diffusion method was employed to evaluate the antibacterial activities of the produced nanoparticles against gram-positive (S. aureus and E. faecalis) and gram-negative (E. coli, S. typhimrium) bacterial strains. Conclusion: The biosynthesized nanoparticles showed promising antibacterial activities with Ag NPs exhibiting the best inhibition activities towards all bacteria species. [ABSTRACT FROM AUTHOR]

Biodiesel has been defined as an alternative fuel that has the potential to be used instead of diesel fuel for years. In case of complete combustion reaction in engines, the products released do not directly threaten human health. Compared to diesel fuel, biodiesel has worse combustion performance due to some fuel properties. Therefore, incomplete combustion products such as hydrocarbon (HC), carbon monoxide (CO), nitrogen oxide (NOx), smoke emission and complete combustion products such as CO2 are thrown into the atmosphere. In this study, the changes in exhaust emissions of 50 ppm and 75 ppm Ag2O NPs were experimentally examined to improve the adverse combustion performance and emission characteristics of cottonseed oil methyl ester. In experiments, nano additive improved the thermal conductivity, mass dissipation and heat transfer of the test fuels, and resulted in reducing of CO emissions as it provided a higher oxidation rate of hydrocarbon molecules. Due to the improvement in the combustion reaction, CO2 emission increased with product of complete combustion. The increase in CO2 emissions was 3.17% and 3.97% for CAg-50 and CAg-75 fuels, respectively, when compared to C0 fuel at 40 Nm load. The NPs additive increased the lower calorific value of the fuel and cylinder temperature. This situation caused increase of NOx emissions by 3.69% and 7.47% CAg-50 and CAg-75 fuels 40 Nm load. Adding of NPs in base fuel reduced to viscosity and density provided better atomization. So a reduction in smoke emission was obtained with NPs addition by 35.09% and 47.32% in CAg-50 and CAg-75 fuels, respectively, compared to C0 fuel at 10 Nm load, while 7.45% and 19.43% at 40 Nm load. [ABSTRACT FROM AUTHOR]

Aim: The current study aimed to compare and evaluate the antimicrobial efficacy of graphene oxide (GO) silver nanoparticle (AgNp) as root canal irrigant (RCI) with other RCIs in maxillary anterior teeth with necrotic pulp. Methods: The GO AgNp RCI was synthesized following modified Turkevich method and subsequent physicochemical characterization was carried out. Sample size was calculated to be 44 and divided into four groups. Following initiation of root canal treatment, preirrigation aerobic and anaerobic samples were collected in suitable medium and the same was done after completion of irrigation adapting the proposed protocol. Further, culture of aerobic and anaerobic samples was done accompanied by determination of bacterial viability count. From the obtained results, statistical analysis was performed and analysis of variance with post hoc was used to compare the antibacterial efficacy between the four irrigants. Results: The statistical analysis ended up with a significant difference in antibacterial properties between GO AgNps and normal saline, 2% chlorhexidine (P < 0.01) against both aerobic and anaerobic organisms. 2.5% sodium hypochlorite and GO AgNp irrigant showed a similar result against aerobic organisms (P = 1.00) while 2.5% sodium hypochlorite was slightly effective against anaerobic organisms (P = 0.83). The bacterial viability counts also showed results in accordance with culture results. Conclusion: From the above results, it can be concluded that the GO AgNp irrigant is an effective biocompatible antimicrobial agent, comparable to that of 2.5% sodium hypochlorite and superior to 2% chlorhexidine and normal saline. [ABSTRACT FROM AUTHOR]

Antimicrobial coatings can inhibit the transmission of infectious diseases when they provide a quick kill that is achieved long after the coating application. Here, we describe the fabrication and testing of a glass coating containing Ag2O microparticles that was prepared from sodium silicate at room temperature. The half-lives of both methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa on this coating are only 2–4 min. The half-life of Clostridioides difficile spores is about 9–12 min, which is extremely short for a spore. Additional tests on MRSA demonstrate that the coating retains its antimicrobial activity after abrasion and that an increased loading of Ag2O leads to a shorter half-life. This coating combines the properties of optical transparency, robustness, fast kill, and room temperature preparation that are highly desirable for an antimicrobial coating. [ABSTRACT FROM AUTHOR]

Herein, the structural, optical, dielectric, and catalytic properties of silver(I) oxide nanoparticles are reported. Fourier transform infrared spectroscopy was used to confirm the main characteristic peaks of silver oxide. X-ray diffraction and high-resolution transmission electron microscopy were used to determine the crystal structure and the particle size of silver oxide. Ag2O has cubic space group P n 3 ¯ m symmetry with crystallite size of 115 nm. After annealing at 423 K for 12 h, the crystallite size increased to 156 nm. The electrical properties of silver oxide nanoparticles are reported over a frequency range from 100 Hz to 7.9 × 105 Hz and at selected temperatures in the range of 298–448 K. It was found that the relaxation process is associated with an activation energy (ΔE = 0.23 eV). Using the Kubelka-Munk function, direct optical band transition values of 1.8 eV and 2.2 eV were found for Ag2O at room temperature (298 K), which decreased to 1.78 eV and 2.18 eV for powder annealed at 423 K for 12 h, respectively. The electrical behavior and conduction mechanism of the silver oxide nanoparticles were studied by Jonscher's law and then the correlated barrier hopping model. The catalytic properties of silver oxide nanoparticles were successfully achieved. Finally, we believe that our study has value for energy applications and environmental remediation. [ABSTRACT FROM AUTHOR]