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This study investigates the fabrication and characterization of electrospun poly (ε-caprolactone)/poly (vinyl pyrrolidone) (PCL/PVP) fibers integrated with a nanocomposite of chitosan, silver nanocrystals, and graphene oxide (ChAgG), aimed at developing advanced wound dressing materials. The ChAgG nanocomposite, recognized for its antimicrobial and biocompatible properties, was incorporated into PCL/PVP fibers through electrospinning techniques. We assessed the resultant fibers' morphological, physicochemical, and mechanical properties, which exhibited significant enhancements in mechanical strength and demonstrated effective antimicrobial activity against common bacterial pathogens. The findings suggest that the PCL/PVP-ChAgG fibers maintain biocompatibility and facilitate controlled therapeutic delivery, positioning them as a promising solution for managing chronic and burn-related wounds. This study underscores the potential of these advanced materials to improve healing outcomes cost-effectively, particularly in settings plagued by high incidences of burn injuries. Further clinical investigations are recommended to explore these innovative fibers' full potential and real-world applicability. [ABSTRACT FROM AUTHOR]

We prepared novel plasmon-coupled silver (Ag) and silver oxide (Ag2O) nanoparticles using green synthesis and a magnetic stirrer device from lemon juice. Firstly, we prepared six Ag samples from green tea and lemon juice, characterized by XRD, FTIR, UV, and HRTEM. We selected just two samples to apply to MDA-MB-231 cells. The samples entered the cell through endocytosis, showed moderate cytotoxicity and ROS levels, caused cell growth arrest at the G2M phase, exhibited higher inhibition of Cyclin D1, and induced early apoptosis. β-Catenin is an abundant protein in triple-negative breast cancer TNBC. Both samples showed inhibition of the β-catenin proteins pathway. Plasmon-coupled nanoparticles effectively inhibited β-catenin, physically capturing β-catenin and its pathway proteins, mimicking the action of a degradation protein complex due to their geometric properties. The prepared materials could be considered a promising treatment for TNBC that has not responded to chemotherapy and radiotherapy. As they have low toxicity to normal cells; this paves the way for new material designs without strict size limitations. [ABSTRACT FROM AUTHOR]

Nanotechnology and nanoscience are due to their numerous uses in medicine, engineering, and water pollution sensors and their expanding research fields. In this study, the essential oil, methanolic extract, and biosynthesized silver/silver oxide nanostructures (Ag/AgO NSs) using the aqueous extract of the plant were prepared. The phytochemical compounds of the extract and essential oil were analyzed using gas chromatography/mass spectrometry (GC/MS), respectively. The GC/MS technique identified 34 compounds in the essential oil of the plant with the major constituents including oleic acid (18.5%), palmitic acid (11.08%), phytone (6.64%), p-vinylguaiacol (6.4%), and phytol (4.23%). After the phytochemical identification, the total flavonoid and polyphenol contents of the extract was determined, too. Prodelphinidin B3 compound in the Malva sylvestris extract was analyzed and detected by high-performance liquid chromatography/ultraviolet detector (HPLC-UV), at a retention time of around 10 min. In addition, M. sylvestris extract was used for green synthesis of Ag/AgO NSs. The as-prepared NPs were characterized using X-ray diffraction (XRD), UV-visible absorption spectroscopy, scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM/EDS), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), and Fourier transform infrared (FT-IR) analyses. Surface plasmon resonance (SPR) absorption at λmax 320 nm in the UV-vis spectra confirms the formation of Ag/AgO NSs. The crystalline structure of Ag/AgO NSs was confirmed by XRD analysis. The nanoparticles were found to have a small size, measuring 64.16 nm, 44.33 nm, and 50 nm using the Williamson-Hall, Scherrer, and SEM/EDS methods, respectively. Besides, that spherical shape of Ag NPs with good size distribution was observed in the SEM/EDS analysis. The small size, around 50 nm, and spherical shape of Ag/AgO NSs with good size distribution were observed in the SEM/EDS analysis. Besides, the antibacterial activity of the extract was evaluated against three pathogenic bacteria, by disk diffusion method. Significant antibacterial activity was observed for the prepared extracts of M. sylvestris against the bacteria (Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa), and the results were compared with the known antibiotics such as amoxicillin, cephalexin, erythromycin, and fluconazole. [ABSTRACT FROM AUTHOR]

Hazardous microorganisms and poisonous pigments found in industrial effluent can have detrimental effects on the environment and human health. This study investigates the synthesis and characterization of graphene oxide (GO), silver oxide (Ag2O) nanoparticles (NPs), and graphene oxide-based silver oxide (GO/Ag2O) nanocomposite, highlighting their enhanced antibacterial and visible light-driven photocatalytic activities. Modified Hummers' method, sol-gel auto-combustion method, and low-cost sonication method were used to prepare GO, Ag2O NPs, and GO/Ag2O nanocomposite with different wt% (1, 5, 10, and 15) of GO, respectively. These synthesized materials were characterized using various characterization techniques such as, UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscope (SEM), and Transmission electron microscope (TEM). Particle size was calculated using Gaussian fitting of XRD, which was found to increase from 20 to 25 nanometres (nm). The optical energy band gap was calculated using a Tauc plot, which decreased from 1.77 to 1.14 electron Volts (eV), respectively. The valence state of Ag (Ag+) for Ag2O, GO-1/Ag2O, and GO-15/Ag2O are confirmed by X-ray photoelectron spectroscopy (XPS). The degradation of methylene blue (MB) dye was done in exposure to sunlight at various time periods using these synthesized materials as photocatalysts to evaluate their photocatalytic activity. GO (15 wt%)/Ag2O nanocomposite showed the best photocatalytic activity among all synthesized materials by the degradation of MB dye to 90% in 120 min under the sun. In addition to excellent photocatalytic activity, GO (15 wt%)/Ag2O nanoparticles exhibited excellent antimicrobial activity. It showed the highest inhibitory range and lowest inhibitory concentration against Staphylococcus aureus and Escherichia coli among all synthetic materials. This demonstrates its potential as a versatile material with excellent photocatalytic and antimicrobial properties, making it promising for many applications in environmental and medical care. [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 nanoparticles (AgONPs) have been revealed to have many applications, including antibacterial behavior. However, the conventional methods for synthesizing AgO NPs often use toxic chemicals that may be detrimental to human health and environmental factors. The crystalline structure and size of obtained AgO NPs were confirmed by Powder X-ray diffraction analysis with 35–70 nm. Functional groups have been identified in Fourier transform infrared spectroscopy. The result of Energy Dispersive X-ray Spectroscopy confirmed the presence of the elements in the synthesized AgO NPs. The energy band gap is determined using UV–visible spectroscopy. Morphological examination of prepared AgO NPs, comprising spherical and rod-like structures, was performed using a Transmission, and scanning electron microscope. The antibacterial activity was evaluated using Gram-negative (Klebsiella pneumonia, Escherichia coli) and Gram-positive (Staphylococcus aureus, Bacillus cereus) bacteria from Agar Well Diffusion Method. The results show that the green synthesis of AgO NPs have better antibacterial activity. The inhibition zone diameter were observedfor all microorganisms. The green synthesis of AgO NPs from herbal plant leaf extracts is a promising method for developing safe and effective antibacterial agents. [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]

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]

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 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]

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]

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]

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]

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]

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]

Nano-PCR is a potential tool for the early detection of plant viruses. In the current study, different concentrations of silver nanoparticles (20 nm) and magnesium oxide nanoparticles (50 nm) were included in the PCR mixture to improve the sensitivity of PCR for the detection of tomato leaf curl virus. The inclusion of nanoparticles in single or combination in PCR mixture has resulted in improvement of PCR sensitivity. Four-fold improvement was exhibited by the inclusion of 3 ng/µL silver nanoparticles, whereas the combination of silver and magnesium oxide nanoparticles (3 ng/µL and 200 ng/µL, respectively), resulted in a 4.5-fold improvement. The inclusion of 200 ng/µL of magnesium oxide nanoparticles in the PCR mixture exhibited a 7.6-fold increase in PCR sensitivity. Replacement of magnesium chloride with a combination of silver and magnesium oxide nanoparticles (3 ng/µL and 275 ng/µL, respectively) resulted in a 12-fold increase. A 13-fold improvement in PCR sensitivity was observed by the replacement of magnesium chloride in PCR buffer with 275 ng/µL of magnesium oxide nanoparticles. This could also produce detectable amplicon in PCR with a minimum of 25 cycles, resulting in a 26.5% reduction in the duration of PCR. This is the first report on the use of magnesium oxide nanoparticles in PCR for the early detection and better management of tomato leaf curl virus. [ABSTRACT FROM AUTHOR]

Samples of reduced graphene oxide aerogels decorated with silver nanoparticles (from 1 to 15 wt %) have been obtained. The reduction of silver ions was performed in the course of the reduction of graphene oxide (GO) and self-assembly of the aerogel with the use of glucose as a green reducing agent. It has been found that all composite graphene aerogel samples GO–Ag have antibacterial properties. The minimum inhibitory concentrations (MICs) of the gram-negative bacteria E. coli and the gram-positive bacteria M. luteus were determined. It was found that the samples GO–Ag10 and GO–Ag15 for E. coli and the samples GO–Ag15 for M. luteus can exhibit both bacteriostatic and bactericidal effects. It was shown that all samples other than GO–Ag15 at MICs effectively inhibited the formation of biofilms of M. luteus bacteria. At the same time, the sample GO–Ag15 at a minimum bactericidal concentration, which is higher than the MIC by a factor of 9.5, effectively destroyed already formed biofilms of M. luteus bacteria. [ABSTRACT FROM AUTHOR]

Ag and ZnO nanoparticles (NPs) were synthesized by a green synthesis from a Pinus latteri tree extraction. Characterizations of the as-prepared Ag and ZnO NPs were determined by DSC/TGA analyses, XRD patterns, and FE-SEM images. The average particles of the as-prepared materials, including Ag NPs and ZnO NPs, are approximately 25 nm and 45 nm, respectively. The XRD patterns confirmed the presence of the Ag metal and ZnO wurtzite crystalline phases. In addition, an agar-well diffusion method was used to evaluate the Escherichia coli (E. coli) antibacterial activity of as-prepared materials. Results show that Ag NPs and ZnO NPs have a high inhibitory ability against E. coli bacteria. Specially, E. coli antibacterial activity of Ag NPs is higher than ZnO NPs under the same conditions. [ABSTRACT FROM AUTHOR]

In this study, undoped tin dioxide (SnO2) thin film and tin dioxide doped with various concentrations of silver oxide (AgO) thin films have been deposited on glass substrates using chemical spray pyrolysis. The developed films were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and UV–visible spectrophotometer to investigate the structural, morphological and optical characteristics. The X-ray analysis showed a polycrystalline nature, and the crystallite size increased from 50.3 to 72.4 nm as the AgO concentration increased. AFM and SEM results showed that the average grain size of SnO2 films increased with the AgO-dopant contents. The topographical analysis of the prepared films showed that the average surface roughness increased from 2.26 to 3.13 nm with an increase in the AgO-dopant material. Optically, the increase in the AgO-dopant content had an optical effect on the tin dioxide films, as the optical transmittance reduced and the refractive index increased. Increase in dopant content reduced the energy gap from 3.75 to 3.6 eV. [ABSTRACT FROM AUTHOR]

The distribution and phytochemistry of the non-nitrogen fixing, filamentous cyanobacterium (blue-green alga) Lyngbya sp., and the inherent antimicrobial and anticancer activities of its phycochemicals as well as of the biosynthesized nanoparticles as their pharmaceutical potencies are considered. Several phycocompounds of curio, apramide, apratoxin, benderamide, cocosamides, deoxymajusculamide, flavonoids, lagunamides, lipids, proteins, amino acids, lyngbyabellin, lyngbyastatin, majusculamide, peptides, etc. were isolated from Lyngbya sp., which had a lot of potential pharmaceutical activities; those compounds had antibacterial, antiviral, antifungal, anticancer, antioxidant, anti-inflammatory, ultraviolet protectant, and other activities. Particularly, several Lyngbya phycocompounds had potent antimicrobial potencies, seen through in vitro controlling of several frequently encountered multidrug-resistant (MDR) clinically belligerent strains of pathogenic bacteria isolated from clinical samples. The aqueous extracts of Lyngbya sp. were used for the synthesis of silver and copper oxide nanoparticles, which were used in pharmacological trials too. The nanoparticles biosynthesized with Lyngbya sp. had several uses such as biofuel, agro-based applications, in cosmetics, and industrial uses as biopolymers, and being potent antimicrobial and anticancer agents and in drug-delivery too, as medical applications. It could be concluded that the Lyngbya phycochemicals and the biosynthesized nanoparticles have future uses as antimicrobial namely as bacterial and fungal and anti-cancer agents, with promising medical and industrial uses. [ABSTRACT FROM AUTHOR]

Spectral optical properties of synthesized ceramic nanoporous membranes based on anodic aluminum oxide coated silver in saturated ammonia gas flow have been experimentally investigated. Based on the measured transmission spectra and detected interference part of the spectra in wavelength range from 550 to 900 nm, temporal and spectral dependencies of the effective optical thickness and its changes in non-equilibrium conditions were obtained due to adsorption of ammonia molecules on silver film surface. According to detected and measured interference maximum shifts up to 14 nm in transmission spectra of Al2O3 + Ag membranes in ammonia gas flow, the possibility of constructing a selective interferometric optical sensors with 10–15 min response time is shown. [ABSTRACT FROM AUTHOR]

Periodontal disease is a set of inflammatory conditions affecting the tissues surrounding the teeth, which can be fairly preventable. In this research, antibacterial polymeric nanofibers were prepared for the management of periodontal disease treatment. New hybrid organic/inorganic nanofibers of chitosan/polyethylene oxide (CS/PEO) contains doxycycline hyclate (DOXH) (as an antibacterial drug) and silver/hydroxyapatite/silica (Ag/HA/Si) nanocomposite (CS/PEO-DOXH-Ag/HA/Si) fabricated by electrospinning technique. The nanofibers were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), field emission scanning electron microscope (FE-SEM), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). In vitro release profile, degradation (DE) test, swelling (SW) test, antimicrobial activity and cell viability were also obtained. The DOXH release profile was measured by ultraviolet visible (UV–Vis) spectrophotometer in artificial saliva (pH 6.8) at 37 °C. The application of Ag/HA/Si increased the morphological integrity during the degradation process and decreased the rate of drug delivery. The electrospun nanofibers showed an enhanced antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Streptococcus mutans (S. mutans) bacterium strains with the lowest DOXH amount, which can reduce the high dosage of antibiotics and side effects. Cell viability assays revealed that the prepared nanofibers had no cytotoxicity against the human gingival fibroblast 2 (HGF-2) cell line. The results suggest that the prepared organic/inorganic hybrid nanofibers with drug delivery properties could be a promising candidate for the treatment of periodontal diseases. [ABSTRACT FROM AUTHOR]

Thermomicroscopy, or hot-stage microscopy, is primarily used in the analysis of organic materials such as pharmaceuticals and polymers. However, its potential application to the study of inorganic systems remains largely unexplored. A thermomicroscope was developed utilising red, green, blue (RGB) colour profiles and individual micrographs taken at fixed temperatures to follow temperature programmed reduction processes under a hydrogen atmosphere. The instrument was used for the study of the reduction in the oxides of silver, copper, lead, and cobalt. To the best of the authors' knowledge, this is the first time that temperature programmed reduction processes have been followed using thermomicroscopy and our results suggest the presence of transient intermediate phases within the lead oxide and cobalt oxide systems. [ABSTRACT FROM AUTHOR]

Polyaniline/nanocarbon (PANI/NC) nanocomposites have been prepared by in situ polymerization of aniline monomer in the presence of a stable colloidal solution of nanocarbon NC using ammonium persulfate as an initiator and silver ions (Ag+) as oxidizing agents to produce PANI/NC and PANI/NC/Ag2O nanocomposites, respectively. The morphological studies of the formed nanocomposites have been elucidated via transmission and scanning electron microscopes (TEM and SEM). Further characterization of the prepared nanocomposites has been done via infrared spectroscopy (IR), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), particle size distribution analysis (PSD), fluorescence microscope (FM), UV–VIS spectroscopy, and finally surface analysis. XRD results confirmed the presence of silver oxide Ag2O nanoparticles, and the obtained data is well matched with the JCPDS card number 76–1393 of silver oxide. XPS analyses have shown two prevailing characteristic peaks for Ag 3d5/2 and Ag 3d3/2 at 367.1 and 373 eV, respectively, representing Ag2O nanoparticles, which are matchable with the XRD analysis. The PSD analysis revealed that the sizes of the prepared nanocomposites are in the size range from 60 to 140 nm. The FM measurements showed luminescence from the prepared nanocomposites upon irradiation with different lights. This recommends that the fluorophores present in the prepared nanocomposites have the potential to both absorb and emit light. The AC conductivity and the dielectric permittivity of the obtained nanocomposites at room temperature and at different frequency ranges have been investigated. At higher frequency ranges, the maximum ac conductivity obtained was 1.06 × 10–2 and 2.5 × 10–2 S.Cm-1 for the PANI/NC and PANI/NC/Ag2O, respectively. As far as we know, these new nanocomposites with superior optical and electrical characteristics have not been described yet in the literature. [ABSTRACT FROM AUTHOR]

Reinforcement of nanoparticles into existing restorative biomaterials in dentistry is an area of interest. The aim of the current investigation was to incorporate silver nanoparticles (SNP) and zinc oxide nanoparticles (ZnONP) into a commercially available resin-modified glass ionomer cement (RMGIC). Their effects on the fluoride (F-) release from RMGIC were also investigated over a period of 14-days. Nanoparticles were incorporated at a loading concentration of 5 wt%, either individually or in a combination of both. Scanning electron microscopy (SEM), Fourier Transform infrared spectroscopy (FTIR), Nanocomputerized tomography (NanoCT), and the Vickers microhardness tester were used to examine the specimens. The fluoride release was analyzed by high performance liquid chromatography (HPLC). Data were analysed using ANOVA and Tukey's test. RMGIC containing 5% ZnONP and 5% SNP + 5% ZnONP showed significant alterations in the surface ultrastructure with pores being evident in the surface. Fluoride release in parts per million (ppm) was highest in the 5% SNP and 5% ZnO-NP incorporated RMGIC compared to the control group and 5% SNP-incorporated RMGIC. RMGIC, as well as change in color observed in the 5% SNP incorporated RMGIC. [ABSTRACT FROM AUTHOR]

Film-like Ag2O coatings have been obtained using electrochemical method, and their photoelectrochemical and spectral properties have been studied. The photocatalytic behavior of these samples in the process of reduction of carbon dioxide with water vapor has been studied. The possibility of formation of a number of organic compounds (acetaldehyde, acetone, isopropyl and ethyl alcohols, methane) upon irradiation of the systems with visible light has been established. [ABSTRACT FROM AUTHOR]

The present study used physics to synthesize silver nanoparticles using aqueous extract of fresh garlic as reducing and as a stabilizing agent silver nitrate solution. This method has proven to be environmentally friendly and safe for the synthesis of stable silver nanoparticles. The acquisition of silver nanoparticles was confirmed by optical detection, that is, by changing the color of the liquid to transparent orange and then blackish brown. Then, the characterization was confirmed using other assays. In this study, it was found that the absorption peak of silver nanoparticles was at a wavelength of 420 nm and the particle size ranged between [50–350] nm. The surface roughness of silver oxide/silver nanoparticles was 9.32 nm with an average square roughness of 21.19 nm, and the energy dispersive spectra showed that the absorption peak was in the region of 3 keV, indicating that the nanoparticles contained crystalline silver. In this study, the stability of the silver nanoparticles was good, as ZP reached (− 19.5). The results confirm that the conductivity increases with the increase in frequency due to the high energy of the photons, which causes the electrons to vibrate in the energy levels and thus increase the energy in the mitochondria and increase the movement of sperm in the Diabetic mice treated with doses of silver nanoparticles. The toxic effect of silver nanoparticles has been evaluated in other studies, in addition to evaluating antioxidants, antifungals, treating cancer cells, regulating cholesterol levels, the effect of these nanoparticles on sex cells in pregnant female mice, heart tension, and many other tests. In this study, the activities and efficacy of silver nanoparticles on sperms were determined in male mice with diabetes caused by STZ, and the treatment period was long (35 days) so that the evaluation period was a complete life cycle of male sex cells and within a long period of time and at an average nano size. This has not been studied in other previous studies. The results indicate that the biosynthesis of silver nanoparticles using garlic plant led to positive results on sperm treatments by contributing to an increase in the number of sperm with reactivation and a decrease in abnormalities in addition to a decrease in mortality due to diabetes. This is evidence that the synthesis of silver nanoparticles using garlic plant size (50–350 nm) can treat impotence and be used in the future in the treatment of many diseases without side effects. [ABSTRACT FROM AUTHOR]

In this paper, we explore the band gap properties of Ag/Ag2O composites synthesized by oxygen plasma treatment of silver thin films as well as the band gap properties of silver nanostructures formed within these composites. The band gap of silver nanoparticles was calculated based on a previous unique result including that the luminescence spectra of the prepared Ag/Ag2O composites contain only features that characterize the various structures of silver nanoparticles. The results obtained showed the formation of energy bands of silver nanoparticles within the energy band structure of the prepared films. Based on the observed features of the luminescence spectra, distinguished energy gaps were found for both individual silver nanoparticles and larger silver nanoparticles. Moreover, the energy gap of individual silver nanoparticles is not significantly affected by neither the size of the silver oxide particles nor the power of the oxygen plasma. [ABSTRACT FROM AUTHOR]

An exploratory work involving waste printed wiring board (WPWB)–derived inexpensive silver oxide (Ag2O)–grafted silica-alumina composite photocatalyst (SAA) using quartz halogen and UVA irradiations (QHUV) (wavelength: 315 nm–1000 nm) has been revealed. The efficacy of the novel SAA photocatalyst was assessed in the synthesis of fermentable sugar (FS) by photo-hydrolysis of pure crystalline cellulose (PCC) in the QHUV-assisted batch reactor (QHUVBR), and the process parameters (5% AgNO3 doping, 7.5% catalyst concentration, 20 min PH time, and 80 °C PH temperature) were optimized using Taguchi orthogonal array design. The BET analysis of the optimal SAA catalyst possessed high surface area (27.24 m2/g), high pore volume, and pore diameter (0.042 cc/g and 13.1684 nm), respectively, whereas the XRD indicated the presence of significant crystalline phases of Ag2O. EDS mapping displayed the uniform distribution of silver active sites on silica-alumina support of the optimal SAA photocatalyst. The optimized parametric conditions in QHUVBR resulted in a maximum FS yield of 77.53% which was significantly higher compared to that achieved (34.52%) in a conventionally heated batch reactor (CHBR). Besides, the energy consumption was 75% more in CHBR (600 W) in comparison with QHUVBR (150 W), making the process energy-efficient and cost-effective. The environmental sustainability could be ascertained from the life cycle assessment (LCA) study in terms of low climate change, ionizing radiation, metal depletion, human toxicity, and other potential indicator values. [ABSTRACT FROM AUTHOR]

A method of template synthesis of nanocrystalline titanium(IV) oxide and its modification with gadolinium(III) and silver oxide nanoparticles have been developed. The composition and structure of the synthesized materials were characterized by X-ray phase analysis and IR spectroscopy. The specific surface area and pore size distribution were determined. The photocatalytic properties of the synthesized TiO2/Gd2O3 and TiO2/Gd2O3/Ag nanomaterials in the degradation reaction of methyl orange aqueous solutions upon irradiation with UV light were estimated. It was found that the introduction of gadolinium(III) oxide increases the photocatalytic activity of the material, and the introduction of silver particles makes the photocatalyst sensitive to light with a shorter wavelength. [ABSTRACT FROM AUTHOR]

Silver oxide nano layers were deposited on SiO2 ‎amorphous substrates by RF reactive magnetron of a silver target (99.999%) in different oxygen gas flow (1, 2 to 3 SCCM) in Ar–O2 reactive gas mixtures. Their crystallography, phase transitions and nanostructures were investigated by X-ray diffraction, SEM, EDAX and AFM analysis. Optical properties ‎were calculated using Kramers-Kronig relations by reflectance spectra. According to X-ray diffraction measurements, at low oxygen flow rate, in addition to cubic phase of Ag, Ag2O phase of silver oxide was observed while, at higher oxygen flow rate only Ag2O crystalline phase was occurred. However, by increasing the oxygen flow to 3 SCCM, target poisoning happened and deposition rate decreased. The SEM images showed that by increasing oxygen flow, dense texture with non-homogenous grains changed to porous morphology. Optical results revealed that the highest optical band gap of 2.7 eV was achieved at highest oxygen flow (3 SCCM) and the highest transmittance of ~ 60% was obtained at same flow. [ABSTRACT FROM AUTHOR]

Currently, nanomaterials with exceptional antibacterial activity have become an emerging domain in research. The optimization of nanomaterials against infection causing agents is the next step in dealing with the present-day problem of antibiotics. In this research work, Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO are prepared by chemical methods. Ag2O was prepared by co-precipitation method, while solvothermal technique was utilized for the synthesis of CoFe2O4. The ternary nanocomposite was synthesized by a simple in situ reduction using a two-step approach. The structural and morphological properties were studied by UV–Vis spectroscopy, X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (SEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR). From the X-ray diffraction analysis, the crystallite size is found to be 14 nm, 5 nm, and 6 nm for Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO respectively. The synthesized nanomaterials were investigated for antibacterial activities against gram-positive strain Staphylococcus aureus (S. aureus) and gram-negative strain Escherichia coli (E. coli) using Agar well diffusion method. Ag2O and CoFe2O4 showed zones of inhibition (ZOI) of 13 mm and 11 mm against gram positive bacteria while 12 mm against gram negative bacteria respectively, while ternary nanocomposite showed 14 mm and 13 mm of ZOI. The antibacterial activity of nanomaterials showed a gradual increment with an increase in the concentration of the materials. Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO showed minimum inhibitory concentration (MIC) values of 4.5, 6.5, and 4.5 μg/mL for S. aureus and 6.5, 7.2, and 4.8 μg/mL for E. coli respectively. Minimum bactericidal concentrations were found to be same as the MIC values. Additionally, a time-kill curve analysis was performed and for ternary nanocomposite; the killing response was most effective as the complete killing was achieved at 3 h of incubation at 3-MIC (9.75 μg/mL). These results demonstrate that all the nanomaterials, as a kind of antibacterial material, have a great potential for a wide range of biomedical applications. [ABSTRACT FROM AUTHOR]

Enhancing stability and antimicrobial properties of nanomaterial and its application in biological field is a burgeoning field of research. In this study, silver nanoparticle decorated graphene oxide (Ag0NP@GO) nanocomposite were synthesized using ecofriendly method. Lantana camara plant extract was selected as a green reducing agent. High phytochemical constituents [Total Phenols—10.44 (TAE) and 9.95 (GAE), Total Tannins—5.98 (TAE) and 5.75 (GAE), Total Flavonoids—8687 mg QE/Kg] in aqueous phytoextract was responsible for the reduction of Ag+ into silver nanoparticles (Ag0NP). The successful formation of nanocomposite was confirmed by the characterization of GO and Ag0NP@GO by UV–VIS, FTIR spectroscopy and XRD. Morphology and size of nanocomposite was confirmed with SEM–EDX and HR-TEM imaging. Results showed that silver nanoparticles (Ag0NPs) with an average size of 51 and 76 nm from Debye-Shrerrer's equation and SEM, respectively were impregnated onto GO sheets. The antibacterial activity of synthesized nanocomposite was tested against bacteria and fungus using Kirby-Bauer test. The zone of inhibition was observed for Bacillus subtilis (21 mm), Staphylococcus aureus (18 mm), Escherichia coli (21 mm), Pseudomonas putida (21 mm) and Candida albicans (31 mm). Complete inhibition of Aspergillus niger was found at 400 mg/L. All results of the present study affirmed the potential applications of Ag0NP@GO as an antimicrobial agent against biological contaminants. [ABSTRACT FROM AUTHOR]

Silver oxide nanoparticles have various biomedical and pharmaceutical applications. However, conventional nanofabrication of Ag2O is associated with the use of toxic chemicals and organic solvents. To circumvent this hurdle, herein silver oxide quantum dots (Ag2O-QDs) were synthesized quickly (3 min) via the use of ultrasonic irradiation and plant-extract. Additionally, due to ultrasonic irradiation's effect on cell-wall destruction and augmentation of extraction efficiency, ultrasonic was also used in the preparation of Mentha pulegium and Ficus carica extracts (10 min, r.t) as natural eco-friendly reducing/capping agents. The UV–Vis result indicated a broad absorption peak at 400–500 nm. TEM/SEM analysis showed that ultrasound introduced a uniform spherical particle and significantly reduced particle size compared to the conventional heating method (∼ 9 nm vs. ∼ 100 nm). Silver and oxygen elements were found in the bio-synthesized Ag2O by EDS. The FTIR and phenol/flavonoid tests revealed the presence of phenol and flavonoid associated with the nanoparticles. Moreover, nanoparticles exhibited antioxidant/antibacterial/antifungal activities. The MIC and MBC results showed the Ag2O QDs synthesized with M. pulegium extract have the highest antibacterial activity against E. coli (MBC = MIC:15.6 ppm), which were significantly different from uncoated nanoparticles (MBC = MIC:500 ppm). The data reflects the role of phyto-synthesized Ag2O-QDs using ultrasonic-irradiation to develop versatile and green biomedical products. [ABSTRACT FROM AUTHOR]

Nanotherapeutic agents play a crucial role in medicine and the bio-nanotechnology field. Because of its cost-effectiveness, plant-based nanoparticle production has sparked a lot of attention, sustainable way, eco-friendly nature, and a plethora of applications. In the present study, the antioxidant and antimicrobial potential of silver nanoparticles (AgNPs) of aqueous extract of Nigella Sativa seeds have been investigated. AgNPs synthesized using N. Sativa extract, characterized by UV-Vis spectroscopy, FTIR, X-ray diffraction (XRD), SEM, and energy dispersive spectroscopy (EDX) techniques showed a peak at 430 nm, with size ranging between 12.97 and 16.37 nm with a spherical shape. Three assays were used to test the antioxidant activity of biosynthesized silver nanoparticles: DPPH, FRAP, and TAC radical scavenging assays, all of which showed strong antioxidant capacity. The disk diffusion method was used for determining the antimicrobial activity of AgNPs. Evaluation of the antimicrobial potential of biosynthesized AgNPs registered the highest inhibitory activity against S. aureus (17.38 mm) followed by E. coli (16.45 mm), B. subtilis (15.5 mm), P. aeruginosa (14.6 mm), and S. Typhimurium (14.35 mm). It was noted that the increased extract concentration in biosynthesized AgNPs leads to a higher zone of inhibition. These results indicated that AgNPs have an effective and strong antimicrobial activity that provides a marvelous source for the development of a new antibacterial drug that can be used for solving the problem of microbial resistance. [ABSTRACT FROM AUTHOR]

A ternary oxide of silver, copper, and manganese (Ag2CuMnO4) is prepared by hydrothermal synthesis in an alkaline medium in the presence of sodium peroxodisulfate. The obtained product with the delafossite structure has no admixtures of other crystallized phases and is tested as an ethylene oxidation catalyst. The catalytic properties of the ternary oxide are modified by pretreatments in inert (He, T = 400-600 °C) and reducing (1% CO/He, T = 200 °C) media resulting in partial or complete destruction of the pristine structure. It is established that pre-treatment of the ternary oxide diminishes its catalytic activity in the ethylene oxidation reaction. The main reaction products are ethylene oxide, acetaldehyde, carbon dioxide, and water; their yields depend on the pretreatment type and the changes during the heating–cooling cycle. [ABSTRACT FROM AUTHOR]

This study illustrates the usage of as-synthesized rGO with different Ag doping ratios as a new designed nanocomposite for enhancing the photodegradation of 2,4 dinitrophenol in aqueous solution under UV-light irradiation. The Ag@rGO nanocomposite was successfully fabricated by a simple and eco-friendly method without deploying any hazardous agent. The synthesized nanocomposite was characterized by SEM, EDX, TEM and XRD to demonstrate the morphological, size distribution, elemental compositions, phase structure and crystalline nature of as-synthesized nanocomposites. The results showed that, the optimum condition for high removal efficiency of 2,4 DNP wad achieved at pH 4–5, 60 min contact time, 0.4 g/L photocatalyst dose and 50 mg/L 2,4 DNP concentration. Furthermore, Ag@rGO 7% showed high degradation efficiency than other prepared nanocomposites. The adsorption isotherm obeyed both Langmuir and Freundlich models with R2 almost > 0.99, while it follows the pseudo-second order kinetics model with Ce values ranging between 11.44 and 25.84 mg/L and corresponding R2 > 0.99. [ABSTRACT FROM AUTHOR]

Ag2V4O11 (silver vanadium oxide, SVO) is the positive electrode in primary lithium/SVO batteries that had known an extraordinary success as a power source in implantable cardiac defibrillators (ICD). However, its use in rechargeable batteries is questioned due to the need of the negative lithium metal electrode that acts as the lithium source and that cannot be safely recharged in standard liquid electrolytes. In this study, a proof of concept of rechargeable graphite/SVO battery is demonstrated. The introduction of 3,4-dihydroxybenzonitrile dilithium salt (Li2DHBN) as a sacrificial lithium source in the positive electrode allows in situ lithiation of the graphite electrode. The cell can further be cycled as a secondary battery. Different parameters have been investigated such as the particle size of Ag2V4O11 synthesized by solid state and hydrothermal processes, especially with regard to peak power delivery. In situ XRD was used to investigate the link between irreversible silver reduction, which allows high electronic conductivity, and amorphization of the SVO structure. [ABSTRACT FROM AUTHOR]

In this work, a low power microcontroller-based near field communication (NFC) interfaced with a flexible abiotic glucose hybrid fuel cell is designed to function as a battery-less glucose sensor. The abiotic glucose fuel cell is fabricated by depositing colloidal platinum (co–Pt) on the anodic region and silver oxide nanoparticles-multiwalled carbon nanotubes (Ag2O-MWCNTs) composite on the cathodic region. The electrochemical behavior is characterized using cyclic voltammetry and chronoamperometry. This glucose hybrid fuel cell generated an open circuit voltage of 0.46 V, short circuit current density of 0.444 mA/cm2, and maximum power density of 0.062 mW/cm2 at 0.26 V in the presence of 7 mM physiologic glucose. Upon device integration of the abiotic glucose hybrid fuel cell with the NFC module, the data from the glucose monitoring system is successfully transmitted to an android application for visualization at the user interface. The cell voltage correlated (r2 = 0.989) with glucose concentration (up to 19 mM) with a sensitivity of 13.9 mV/mM•cm2. [ABSTRACT FROM AUTHOR]

The advancement in conservationist strategies for development of nanoparticles is elemental to the subject of nanotechnology. Green protocols are highly preferred over conventional methods as they are environmentally benign. Certain phytochemicals in plant extracts exhibit natural tendencies of bio-reduction of salts. They also possess the ability of stabilizing these reduced particles by capping them. In present study leaf extract of Catharanthus roseus, an evergreen subshrub has been utilized for production of AgNPs and CuO-NPs. Synthesized nanoparticles were evaluated for their cadmium, chromium removal and antibacterial potential against S. aureus. AgNPs and CuO-NPs were optimized by varying salt concentration, leaf extract concentration and time interval to obtain better yield. UV–Vis spectroscopy was used to detect biogenic AgNPs and CuO-NPs. Wavelength range used for AgNPs and CuO-NPs was 300–700 and 200–700 nm successively. The morphology of nanoparticles was determined to be spherical and within 100 nm using SEM images. FT-IR investigation confirmed the presence of amines and alcohols in AgNPs. IR spectra of CuO-NPs revealed the ubiety of aldehydes/ ketones and carboxylic acids. The average distribution for silver was 602.9 nm and for copper was1066 nm as confirmed by DLS analysis. Further zeta-potential for AgNPs and CuO-NPs was recorded -16.4 mV and -6.18 mV. Kirby Bauer test for S.aureus show maximum ZOI i.e. 16 mm in case of AgNP (50 µl) and 10 mm in case of CuO-NP (50 µl). Highest chromium and cadmium removal was observed in case of biogenic silver nanoparticles i.e. 47.84% and 5.68% respectively. This is the first work that presents a comparative study of biogenic AgNPs and CuO-NPs from the leaf extract of Catharanthus roseus. Our findings can also help in improving the current scenario of metalloid pollution in soil and water environments. Hence, proper scaling up can make biogenic AgNPs and CuO-NPs a noteworthy tool in industries as well. [ABSTRACT FROM AUTHOR]

The study focuses on a non-stringent, rapid and sustainable way for the synthesis of silver oxide nanoparticles (Ag2ONPs) using aqueous rhizome extract of Curcuma zanthorrhiza Roxb. (Cz). High resolution liquid chromatography mass spectroscopy (HR-LCMS) was used for the simultaneous identification of bioactive molecules in the aqueous rhizome extract and its biosynthesized nanoparticles. The presence of eleven bioactive molecules in the rhizome extract acts as reducing and capping agents during the synthesis of Ag2ONPs. The molecules coated to Ag2ONPs were identified to be majorly sesquiterpenoids and lipid molecules. The analytical techniques used for the nanoparticle characterization included UV–Visible spectrum, which showed SPR band at 409 nm; FTIR spectrum depicted the bioactive molecules involved in capping and reduction of silver ions to silver oxide nanoparticles; XRD pattern attributed to fcc structure of CzAg2ONPs with an average size of 39.7 nm; HR-TEM and FESEM confirmed the size and morphology of CzAg2ONPs. The chemical nature of the bioactive molecules bound to Ag2ONPs revealed by HR-LCMS was in agreement with FTIR spectral data. The CzAg2ONPs exhibited efficient photocatalytic activity in the degradation of the toxic dye malachite green (MG) as revealed by the absorption spectra. The degraded product was subjected to HR-LCMS and found to be non-toxic. The results revealed the promising potential of bioactive molecules coated Ag2ONPs for environmental cleanup. [ABSTRACT FROM AUTHOR]

Foam-like binary Cu2O/Ag2O nanoheterostructures have been obtained by an electrochemical method. Their photoelectrochemical and spectral properties have been studied. The photocatalytic properties of these composites in the process of gas-phase reduction of carbon dioxide with water vapor have been studied. The formation of binary nanoheterostructures leads to an increase in methane yield and an increase in the amount of other organic products (acetaldehyde, ethylene, and ethanol) while the system is irradiated with visible light when compared to Cu2O. This effect can be explained by the formation of a nanostructured Cu2O/Ag2O binary composite with a mutually consistent energy profile. [ABSTRACT FROM AUTHOR]

In this study, silver oxide nanoparticles (Ag2O-NPs) were synthesized from silver nitrate using green amaranth leaf extract as a reducing agent. The degradation of caffeine and inactivation of Escherichia coli (E. coli) by Ag2O-NPs was studied under compact fluorescent lamp illumination irradiation. Apart from that, the antibacterial and antioxidant activities of Ag2O-NPs were also examined. Synthesized Ag2O-NPs were shaped like monodispersed husk, and cubic structured with surface area, and average particle size was detected to be 100.21 (m2/g) and 81 nm, respectively. Antioxidant efficacy of the Ag2O-NPs was evaluated using 1, 1-diphenyl-2-picrylhydrazyl, and 91% inhibition was achieved with 100 µg Ag2O-NPs. Cell viability assay demonstrated that Ag2O-NPs showed less cytotoxicity for human embryonic kidney (HEK 293) cells. The bacteriocidic propensity of Ag2O-NPs was examined against the S. aureus and P. aeruginosa by disk diffusion, minimum inhibitory concentration (MIC), live and dead assay. It was observed that the NPs have a higher bactericidal effect on Gram-negative as compared to Gram-positive bacteria. Up to 96%, photocatalytic inactivation of E. coli was achieved using 30 µg/mL of NPs. Photocatalytic degradation of caffeine (50 ppm initial concentration) was observed to be 99% at pH 9 in 15 h using 50 mg/L of Ag2O NPs. These results indicate that Ag2O NPs can be employed in environmental applications like harmful bacteria inactivation and organic pollutants degradation. [ABSTRACT FROM AUTHOR]

A connected ground 4-port wideband transparent antenna is proposed. The structure attains optical transparency due to AgHT-8 (Silver Tin Oxide) and Plexiglass. The geometry of a single radiating element consists of a U-shaped patch connected with a semicircular arc and an inverted L that is fed through a microstrip line. The antenna has a full ground plane along the vertical direction and is truncated along the horizontal directions. The antenna geometry is replicated to form three different 4-port MIMO structures where the first one has a separate ground profile while the latter comprises 2 different (O and H shaped) connected ground profiles. The proposed structure is decided after evaluating the isolation levels while achieving the required frequency bands of operation. At the lowest frequency, the antenna size is 0.092λ × 0.165λ. Impedance bandwidth of (121.36%) 0.69–2.82 GHz over a − 10 dB band with isolation better than 20 dB amid all elements is achieved. The antenna is assessed in terms of MIMO diversity, scattering, and transmission parameters by simulating the antenna followed by experimental results which depict a decent correlation. The average gain and efficiency above 0.5 dBi and 40%, respectively with optical transparency, connected ground, satisfactory isolation, and diversity parameters make the transparent 4-port MIMO antenna suitable for GSM (850/900/1800/1900), LTE (700/2300/2500), UMTS (2100), Bluetooth (2400) and WLAN (2400) applications where device aesthetics, location issues, and visual clutter need to be mitigated. [ABSTRACT FROM AUTHOR]

Biosynthesis of nanoparticles is the preferred route for the fabrication of biocompatible and cheaper drugs. In this study, the extract and major secondary metabolite from Helichrysum aureonitens, 3,5-dihydroxy-6,7,8-trimethoxyflavone, were used to synthesize silver and zinc oxide nanoparticles. Spectroscopic and microscopic techniques confirmed the formation of the nanoparticles. The flavone alone showed higher DPPH radical scavenging ability (IC50 = 487.1 μg mL−1) relative to the control, butylated hydroxytoluene. In addition, silver nanoparticles synthesized using the flavone had higher ferric reducing potential (Fe3+ to Fe2+) compared to the other test samples. The cytotoxic activity of the plant extract, the flavone, and their biosynthesized nanoparticles was also investigated using the MTT assay against the cancerous MCF-7 (breast adenocarcinoma) and A549 (human lung adenocarcinoma)), and non-cancerous HEK293 (human embryonic kidney) cell lines. The plant extract decreased the cell viability of A549 (IC50 = 68.6 μg mL−1) without being cytotoxic against HEK293, even at high concentrations. Silver nanoparticles significantly decreased cell viability of A549 and moderately decreased cell viability of MCF-7 but induced cell death of HEK293 even at low concentrations. This study provides a green synthesis route for silver and zinc oxide nanoparticles and confirms the therapeutic effectiveness of H. aureonitens, thereby validating its use in ethnomedicine. [ABSTRACT FROM AUTHOR]

We present the results of investigations of the influence of a filtering layer of silver and magnesium-oxide (MgO–Ag) nanoparticles on the hardness of water and admissible contents of iron and phosphorus. It is shown that, by using a layer of this kind, it is possible to decrease the contents of iron and phosphorus. It is also established that, in view of the saturation of water with particles of silver and magnesium oxide, the hardness of water decreases and we get a better chemical composition of tap water. [ABSTRACT FROM AUTHOR]

Nanoparticles today have the upper hand in its manufacturing desirability in more or less every aspect of the working areas, from industrial and commercial to self-care products. In this paper, the applicational prospects of varistors for the composite mixture of rGO and Ag-nanopowders were studied via samples with varying compositions. Hummers modified method and burst method were employed for the synthetisation of GO, rGO, and Ag-nanopowders, respectively. The structural nature and electrical behaviour were understood by the means of variegated characterisations. The purity of GO and rGO were confirmed via Raman analysis. XRD and FTIR exhibited the attributed peak values for GO and rGO, Ag-nanopowders. The topographical and elemental details were acquired through FESEM and EDX studies, which talked about the wrinkled paper-like structure for GO and rGO and spherical structural nature of Ag. Current–voltage plot was studied for the better understanding of the electrical inhabitation. It was observed that rGO + Ag, being two constituent networks, gave small values but still showed an increase, which means if used with complex arrangement, they have the possibility to be considered in the material fabrication for high-voltage varistors domains. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are rapidly adopted in agriculture to improve plant growth and development. Nano-priming is one such strategy that utilizes NPs to enhance seed germination, seedling vigor, and improve crop resilience. This study is the first attempt to compare the effects of silver and titanium oxide NPs (TcAgNPs and TcTiO2NPs) myco-synthesized using Trichoderma citrinoviride extract as seed priming agents. Different concentrations of TcAgNPs and TcTiO2NPs (25, 50, 100, 200, and 400 µg/mL) were tested for priming Solanum lycopersicum seeds, and the effect on seed germination, seedling growth, chlorophyll, antioxidant mechanism, and carotenoid content were evaluated. The study revealed that lower concentrations of TcTiONPs (25 and 50 µg/mL) had a positive effect on seed germination and seedling vigor. However, unlike TcTiONPs, lower concentrations of TcAgNPs reduced the seed germination, seedling vigor, and showed an increase in the activities of antioxidant enzymes such as catalase, superoxide dismutase, and peroxidase. The differences in the response for both NPs can be attributes to their surface charge, and concentration used. Overall, myco-synthesis of TcAgNPs and TcTiONPs can work as a green route to reduce the dependence on chemical mediated production of NPs for seed priming with the potential to improve the germination and development of tomato. [ABSTRACT FROM AUTHOR]

Nickel oxide and silver oxide nanoparticles have wonderful properties that could be employed in numerous applications. Thus, synthesis of nickel silver oxide nanostructures with different characteristics is of great interest. In this review, many synthesis methods were reported such as: electrodeposition, electrochemical method, simple immersion process and subsequent RF-sputtering deposition, chemical oxidative polymerization, followed by acidic sol–gel process, flame-based process, liquid-phase reduction technique, sol–gel, hydrothermal method, co-precipitation method, simple precipitation method, thermal decomposition, chemical wet synthesis, low and high-temperature reduction, high-pressure autoclave, thermal treatment method, and laser-liquid–solid interaction technique. Reporting all methods employed for the fabrication of NiO and Ag2O nanostructures is useful to produce and develop novel nanomaterials with enhanced properties and applications. Studying the factors that tuned their properties: particle size, shape, and capping agents as well as solution pH is highly recommended in future works. Also, further research studies should be conducted for finding another/other facile and effective synthesis method/methods. [ABSTRACT FROM AUTHOR]