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Metal ion-induced water pollution is attracting increasing public attention. Perovskite quantum dots and metal–organic frameworks (MOFs), owing to their outstanding properties, hold promise as ideal probes for detecting metal ions. In this study, a composite material, MAPbBr3@PCN-221(Fe), was prepared by encapsulating MAPbBr3 quantum dots with PCN-221(Fe), demonstrating high chemical stability and good reusability. The composite material shows a sensitive fluorescence turn-on signal in the presence of silver ions. The fluorescence intensity of the composite material exhibits a linear relationship with the concentration of Ag+ in the solution, with a low detection limit of 8.68 µM. Moreover, the fluorescence signal exhibits a strong selectivity for Ag+, enabling the detection of Ag+ concentration. This fluorescence turn-on signal originates from the Ag+-bridged energy transfer from the conductive band of MAPbBr3 to the excited state of the MOF, which is directly proportional to the concentration of silver ions. Simultaneously, this finding may open up a new possibility in artificial controlled energy transfer from perovskite to MOF for future development. [ABSTRACT FROM AUTHOR]

Chiral molecules can exhibit strong spin–orbit coupling, which can result in a large spin polarization. This is due to the fact that the energy levels of the electrons in a chiral molecule are strongly influenced by the chiral structure of the molecule, which can result in the separation of the energy levels for electrons with different spin orientations. We report a controlled spin-selective transmission of electrons through 20 base-paired poly-cytosine molecules functionalized with MoS2 flakes on ITO glass via the quantum mechanical tunneling effect. A reversion in spin polarization was observed after the silver ions interact with poly-cytosine due to the strong coordination of Ag(I) with cytosine–cytosine (C–C) mismatches, indicating the formation of duplex structural motifs, as confirmed by the circular dichroism spectroscopy at room temperature. Manipulating the spin of an electron through such a small molecule merely controlled by special cations could pave the way for major advances in spin-independent charge transport, advanced bioanalytical system design, and related applications. [ABSTRACT FROM AUTHOR]

Chiral molecules can exhibit strong spin–orbit coupling, which can result in a large spin polarization. This is due to the fact that the energy levels of the electrons in a chiral molecule are strongly influenced by the chiral structure of the molecule, which can result in the separation of the energy levels for electrons with different spin orientations. We report a controlled spin-selective transmission of electrons through 20 base-paired poly-cytosine molecules functionalized with MoS2 flakes on ITO glass via the quantum mechanical tunneling effect. A reversion in spin polarization was observed after the silver ions interact with poly-cytosine due to the strong coordination of Ag(I) with cytosine–cytosine (C–C) mismatches, indicating the formation of duplex structural motifs, as confirmed by the circular dichroism spectroscopy at room temperature. Manipulating the spin of an electron through such a small molecule merely controlled by special cations could pave the way for major advances in spin-independent charge transport, advanced bioanalytical system design, and related applications. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a potent neuromodulator in the brain that affects a wide range of motivated behaviors. Abnormal concentration of DA is related to a variety of diseases. Hence, it is imperative to establish a rapid and precise method for quantifying DA. In this work, we integrate orange-yellow emissive carbon dots (CDs) with target-induced silver deposition on gold nanoparticles (Au NPs), forming gold/silver core-shell nanoparticles (Au@Ag NPs), to construct a fluorometric and colorimetric dual-signal sensor for sensitive detection of DA. Au NPs and silver ions (Ag+) have minimal effect on the fluorescence of CDs. DA can reduce the silver ions to Ag(0) on the surface of the Au NPs to form a silver shell, resulting in the blue-shift of the absorbance peak from 520 to 416 nm, which overlaps with the excitation spectrum of CDs. As a result, the system color turns from pink to orange-yellow, and the fluorescence of CDs is quenched due to the strong inner filter effect. The linear range of the colorimetry is 0.5–18 μM with a limit of detection (LOD) of 0.41 μM, while the linear range for the fluorometry method is 0.5–14 μM with a LOD of 0.021 μM. This method demonstrates notable advantages including a low detection limit, rapid response time, and straightforward operation in practical samples, showing great potential in biomedical analysis. [ABSTRACT FROM AUTHOR]

The preparation of scaffolds that are both macroporous and mechanically strong is a significant challenge in the development of bioactive ceramic materials for bone substitution. Furthermore, the introduction of beneficial extra-functionalities such as bacterial inhibition is highly appealing but adds complexity to implant design and production. In this study, we aimed to fabricate highly porous, bioactive and antibacterial glass-ceramic scaffolds with interconnected macropores through the foam replica method. The scaffolds were sintered at two different temperatures (620 and 850 °C), yielding glassy or partially crystallized materials, respectively. The scaffold produced at higher temperature was found to be highly porous (>75 vol%), mechanically stronger and able to induce hydroxyapatite formation after three days of soaking in SBF (in vitro bioactivity). In order to confer antibacterial activity, silver (Ag) ions were introduced onto the scaffold surface through ion exchange in an aqueous solution. Compositional analysis confirmed the successful doping of the scaffold surface with silver, which was continuously released in SBF for at least 28 days, as revealed by ICP-MS. Finally, the antibacterial action of the Ag-doped scaffold was confirmed towards Staphylococcus epidermidis. Overall, the results reported in this work show the potential of foam-like Ag-doped bioactive glass-ceramic scaffolds to be used in applications requiring bone substitution and antibacterial properties. [ABSTRACT FROM AUTHOR]

The simplified local density (SLD) model was employed to analyze the experimental results of the adsorption of dimethyl sulfide (DMS) from a model fuel (n-hexane) on raw and modified walnut shell activated carbon (WSAC) with different impregnated amounts of silver ions (Ag-2, 4, 6, 8, and 10 mass percent). Modified Peng–Robinson equation of state was used in the liquid phase and the 6-12 Lenard Jones (LJ) potential function was implemented to represent the solid-fluid interactions. The LJ parameters for pure DMS and n-hexane were obtained from the Tsonopoulos correlation for the Second Virial coefficient data. Published experimental results of DMS and n-hexane adsorption were used for the physical properties and the molecular parameters needed in SLD model. Excess adsorption amounts of DMS were then calculated and compared with the experimental data. The average absolute deviations (AAD) between the experimental data and calculated results were 0.0072, 0.0727, 0.0377, 0.0601, 0.0605, and 0.0634 mmol/gr adsorbent for WSAC, WSAC-Ag-2, WSAC-Ag-4, WSAC-Ag-6, WSAC-Ag-8, and WSAC-Ag-10, respectively. For the same adsorbents the percent average absolute relative deviation (AARD%) were 14.11, 15.50, 7.70, 15.48, 16.16, and 29.09, respectively. The applicability of the SLD model in liquid-phase adsorption is validated. [ABSTRACT FROM AUTHOR]

In this work, new pH‐sensitive and antibacterial drug carrier systems based on silver nanoparticles (AgNPs) embedded in the interlayer of laponite (Lap) in the presence of chitosan (CTS) for the controllable release of sunitinib maleate (STM) were developed. Silver ions and sunitinib maleate were first loaded into Lap, and the CTS‐based hybrid bionanocomposite carrier (Lap@CTS@AgNPs@STM) was obtained in the presence of citric acid as a cross‐linker agent. The successful preparation of nanocarrier and Ag NPs formation was thoroughly confirmed using techniques such as FTIR, XRD, TGA, SEM, and TEM. TEM images illustrated the excellent distribution of Ag NPs in the structure of Lap@CTS@AgNPs. The as‐prepared samples showed a pH‐sensitive anticancer drug release behavior. The STM release mechanism was studied using Korsmeyer–Peppas and Higuchi kinetic models. Furthermore, the in vitro cytotoxicity and antibacterial tests were carried out against both bacteria S. aureus and E. coli and MCF‐7 cell lines, respectively, to prove the effectiveness of synthesized samples as multifunctional carrier systems for biomedical applications. [ABSTRACT FROM AUTHOR]

This study is aimed at the synthesis of nanoparticles (NPs) and nanocomposite (NC) using maize leave as precursor. Silver NPs (AgNPs) and AgNCs were synthesized from silver nitrate and maize leave extract using green approach. The maize leave NPs (AgNPs) and the maize leave NCs (AgNCs) were characterized using Fourier Transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersion x-ray (EDX), Brunauer–Emmett–Teller (BET) surface area measurement, and dynamic light scattering (DLS) particle size analysis. The phytochemical analysis revealed the presence of tannin, oxalate, and flavonoids in appreciable quantity, which have proven to be a powerful reducing agent that facilitates the reduction of silver ions for the synthesis of silver NPs and silver nano composites. FTIR revealed that all the peaks identified in AgNPs and AgNCs belong to the characteristic bands of reducing compounds such as flavonoid compounds. The SEM-EDX results showed that the peaks observed from 2.9 to 3.1 Kev in the spectra indicate the presence of elemental silver as it is reduced from Ag+ to Ag. DLS analysis results showed that the average size and polydispersity index (PdI) of the synthesized AgNPs and AgNCs were 42.30 and 68.29 nm, 0.691 and 0.270, respectively. The single point BET surface area (m2/g) obtained for AgNPs and AgNCs were 223.3 and 209.5, respectively. The results showed maize leave as a potential precursor for the preparation of NPs and NCs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mesoporous‐nanostructured silica‐Prussian blue composite is a highly potential material for silver ions removal and recovery from wastewater. Intense interest has been shown in the use of Prussian blue (PB), one of the important coordinated materials and its analogues in removal of toxic and valuable ions. METHODS: The micro‐emulsion template method enables the synthesis of Prussian blue (PB) within silica pores, yielding a nanostructured mesoporous silica‐PB composite. This rapid synthesis technique allows for the direct fabrication of the composite from mixed precursor solutions within minutes. The resulting material is effective for selectively extracting silver ions from wastewater at a specific pH level. RESULTS AND DISCUSSION: In summary, the synthesized SiO2‐Prussian blue composite was extensively analyzed using various techniques including XPS, HR‐TEM, SEM, STEM‐EDX elemental maps, TGA/TDA, and N2 adsorption/desorption measurements. The composite exhibited a BET surface area of 203 m2 g−1 and a total pore volume of approximately 0.283 cm3 g−1with mesopores centered around 20 nm. This mesoporous SiO2‐Prussian blue demonstrated significant effectiveness in removing silver ions, with a maximum adsorption capacity of 107.5 mg g−1. The Langmuir and Sips isotherms showed the best fit among various adsorption isotherm types, with R2 values exceeding 0.984. Additionally, kinetic analyses revealed that the pseudo‐second‐order model accurately described the adsorption of silver ions onto the synthesized adsorbent. The nano‐particles exhibit remarkable long‐term stability, maintaining good reproducibility even after five regeneration cycles. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Silver ions possess inherent antioxidant properties, whereas hydroxyapatite (HAP) is a structural support within the body. The research methodology involves synthesizing HAP and 3% silver‐doped hydroxyapatite (Ag‐HAP) via the sol–gel method, followed by comprehensive characterization using X‐ray diffraction, Fourier transform infrared, Raman spectroscopy, and field emission scanning electron microscopy, antioxidant, thrombogenicity, and cell viability. The investigation reveals that Ag‐HAP exhibits superior antioxidant properties and thrombogenicity compared to other metals doped so far. Remarkably, Ag‐HAP demonstrates moderate clotting behavior compared to HAP. Additionally, the (3‐(4, 5‐dimethythiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide) MTT assay evaluates cellular viability, shedding light on the biocompatibility of the materials. The study uncovers the potential of silver doping to enhance the antioxidant capabilities of HAP significantly, offering promising prospects for orthopaedic implants. The antioxidant activity of the materials is evaluated through a 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging assay, whereas the thrombogenicity is assessed using a whole blood clotting method. The improvement indicates that incorporating silver ions influences HAP crystalline structure and increased grain size, contributing to enhanced antioxidant efficacy and favorable cellular responses, thus underlining the potential of Ag‐HAP for advanced implant materials in orthopaedic surgery. The results also discuss that how Ag‐HAP is better than Co‐HAP. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were biosynthesized from a crude leaf extract of Rhizophora mucronata. The initial phytochemical analysis of the sample revealed the presence of tannins, steroids, terpenoids, saponins and flavonoids which contribute to the reduction and stabilization of silver ions during the synthesis process. Characterization techniques, including FTIR, UV–Vis spectroscopy, SEM and EDS, confirmed the successful synthesis of AgNPs with distinctive properties. The UV–Vis spectra exhibited an absorption peak around 420 nm, characteristic of AgNPs. SEM images revealed the crystal nature of the nanoparticles, indicating structural stability. The agar well-diffusion method was employed to determine the zone of inhibition against different pathogens. The leaf extract demonstrated the highest antibacterial potential, with substantial zones of inhibition observed against all tested pathogens. The potent anti-inflammatory activity showed the minimum and maximum inhibition of protein denaturation at concentration of 25 μg/mL and 100 μg/mL are 28% and 69%, respectively. The silver nanoparticles demonstrated anti-inflammatory properties by inhibiting protein denaturation, suggesting their potential therapeutic applications. The mangrove R. mucronata leaf extract decided to be a favorable reducing agent for the biological synthesis of silver nanoparticles with potent antimicrobial activity. [ABSTRACT FROM AUTHOR]

This study investigates the effect of Ag-doping on the (001) surface of SrTiO 3 (STO) to enhance hydrogen production via water-splitting employing density functional theory (DFT) simulations. It was found that the heterolytic water dissociation on Ag-doped (001)-STO occurs via a first-order reaction with an energy barrier of 5.74 kJ/mol, representing a reduction of 94% compared to undoped (001)-STO. The Gibbs free energy of H 2 formation catalyzed by Ag-doped (001)-STO is approximately −302 kJ/mol, indicating the spontaneity of this process. Additionally, the surface band gap energy decreases by ∼2 eV after water-splitting, suggesting charge transfer from the Ag-doped STO to the water and leading to new electron-hole recombination states. This research underscores the potential of Ag-doping in enhancing the efficiency of hydrogen production through water-splitting, contributing to the development of greener and more efficient energy technologies. • Ag-(001)-STO catalyzes H 2 formation spontaneously, indicating potential for hydrogen production. • Ag-doped (001)-STO reduces water dissociation energy barrier by 94%, enhancing catalytic activity. • Water interaction induces resonance states in Ag-doped (001)-STO, lowering band gap by 0.95 eV. • Electronic analysis reveals midgap and low electron mobility bands in transition state, crucial for water-splitting. • The study contributes to photocatalysis by elucidating Ag-doping impact in perovskite semiconductors. [ABSTRACT FROM AUTHOR]

In this work, silver nanoparticles (AgNPs) were synthesized from cashew nutshell liquid (CNSL) by varying the concentration of silver ions and the pH of the CNSL extract. The synthesized AgNPs were further characterized to study their surface, structural, and morphological properties and tested for the removal of methylene blue (MB) dye. The results of this study showed that depending on the conditions, particles of various sizes, ranging from 1 to 60 nm, and different degrees of stabilization and agglomeration were produced. The concentration of silver ions equal to 3 mM and the pH of the extract of ~4.5 (AgNP3) resulted in the most efficient synthesis, where particles appeared to be highly stabilized and homogeneously distributed on the surface, exhibiting a small average particle size and a narrow particle size distribution (6.7 ± 6.5 nm). Such particles further showed the highest percent removal of MB, where up to 80% removal was recorded within the first 20 min. Higher concentrations of silver ions and higher pH of the extract resulted in substantial particle agglomeration and particles being over-capped by the CNSL biomolecules, respectively, which further negatively affected the ability of particles to remove MB. Finally, the fact that visible light showed no significant effect on the removal of MB, with the average removal rates found to be about the same as in the dark, suggests the strong catalytic nature of AgNPs, which facilitates the electron transfer reactions leading to MB reduction. [ABSTRACT FROM AUTHOR]

Objective: This systematic review aims to evaluate the potential benefits and underlying mechanisms of combining SDF with light curing, based on available studies. Materials and methods: A systematic search of publications was conducted with the keywords "silver diamine fluoride" or "silver fluoride" and "dental light curing," "LED curing," "dental laser," and "dental polymerization" in 4 databases: PubMed, EBSCO, Scopus, and Google Scholar to identify English-language articles published up to March 2023. Duplicate publications were deleted. Two reviewers screened the titles and abstracts and excluded irrelevant publications. The full text of the remaining publications was retrieved. Studies investigating the effect of light-curing on SDF-treated carious lesions were included. Results: The 175 publications initially found included 5 laboratory studies investigating the effects of light curing on 38% SDF-treated dentine carious lesions, but no clinical study was found. Four of these studies were conducted on extracted primary teeth, and one was on extracted permanent teeth. SDF with light curing increased microhardness (n = 3, p <.05) showed a higher mineral density (n = 1, p <.041) and had more silver ion precipitation in infected dentine (n = 1, p <.016) compared to SDF without light curing. Moreover, no significant differences in the antibacterial activity were observed between SDF with light curing and SDF alone (n = 1, p >.05). Conclusion: Drawing from the limited number of laboratory studies, incorporating light curing subsequent to the SDF application yields potential favorable outcomes that include augmented microhardness, elevated mineral density, and heightened silver ion precipitation within infected dentine. Future clinical research is required to confirm or refute the benefit of light curing on SDF-treated carious lesions. [ABSTRACT FROM AUTHOR]

In situ metallization of Ag+ conductive glass was successfully achieved by applying electric and temperature fields to the glass to ensure the controlled migration of ions inside the glass. The transport and kinetic characteristics of Ag+ under the combined effect of electric field and temperature field were investigated by calculating and analyzing Ag+ diffusion coefficient. The correlations between ion transport and current were characterized with potential energy equations. The simulations and experiments of ion transport in the conducting glass were implemented, which revealed the mechanisms of ion transport and interfacial precipitation within the conducting glass. Further more, the existence of Ag+ deprivation layer was confirmed and it was clarified that the depth of the deprivation layer reached 30 µm under thermal polarization conditions of 60 V and 300°C. The microscopic morphology of in situ silver deposition layer was observed using SEM and TOF–SIMS. In addition, It was determined that the in situ metallization of conductive glass under the polarization condition of 60 V at 250°C was the best, and the thickness of deposited silver dendrites reached 1000 nm in the side of cathodically. This paper provides theoretical and experimental references for the optimization of the in situ metallization process for the ion conductive glass. [ABSTRACT FROM AUTHOR]

Implant infections are a major challenge for the healthcare system. Biofilm formation and increasing antibiotic resistance of common bacteria cause implant infections, leading to an urgent need for alternative antibacterial agents. In this study, the antibiofilm behaviour of a coating consisting of a silver (Ag)/gold (Au) nanoalloy is investigated. This alloy is crucial to reduce uncontrolled potentially toxic Ag+ ion release. In neutral pH environments this release is minimal, but the Ag+ ion release increases in acidic microenvironments caused by bacterial biofilms. We perform a detailed physicochemical characterization of the nanoalloys and compare their Ag+ ion release with that of pure Ag nanoparticles. Despite a lower released Ag+ ion concentration at pH 7.4, the antibiofilm activity against Escherichia coli (a bacterium known to produce acidic pH environments) is comparable to a pure nanosilver sample with a similar Ag-content. Finally, biocompatibility studies with mouse pre-osteoblasts reveal a decreased cytotoxicity for the alloy coatings and nanoparticles. [ABSTRACT FROM AUTHOR]

Film heterostructures of compositions Ag/Au/Ti and Ag/Au/CFR-PEEK are obtained by thermal evaporation with subsequent deposition of metallic gold sublayers and silver nanostructures on modern biomaterials (Ti-6Al-4V alloy, polyether ether ketone CFR-PEEK). Silver concentration is varied within 2.1-20.8 µg/cm2 by changing the initial metal portion (1.2-5 mg) and the number of successive depositions (1–3). According to SEM data, Ag nanofilms with a thickness up to 10-15 nm are formed on the surface of gold sublayers. According to XPS results, gold is present in the metallic state on the surface of biomaterials whereas along with metal, the Ag2O oxide phase is detected for silver. The dynamics of silver dissolution from the Ag/Au surface is analyzed by ICP-AES (2-48 h). It is found that regardless of the silver concentration, the samples demonstrate moderate dynamics of releasing metal ions; some amount of gold is detected together with silver in the solution. The absence of cytotoxicity of the synthesized film heterostructures in vitro (L-929 cells, viability >95-98%) is shown. Heterostructures completely suppress the growth of colonies of Gram-negative (P. aeruginosa) and Gram-positive (S. aureus) bacteria after 6 h and 24 h action respectively. [ABSTRACT FROM AUTHOR]

Bacterial infections account for countless deaths globally. Antibiotics are the primary countermeasure; however, the alarming spread of antibiotic‐resistant strains necessitates alternative solutions. Silver and silver compounds have emerged as promising antibacterial agents. However, issues related to cytotoxicity and genotoxicity of silver remain concern. To overcome these challenges, this proposes an easy‐to‐control and straightforward method to synthesize novel Silver─gallium (Ag─Ga) nano‐amalgamated particles. Gallium liquid metal (GaLM) is used to facilitate the galvanic deposition of silver nanocrystals (Ag) on oxide layer. The GaLM not only serves as a carrier for silver through the galvanic replacement process, but also provides a controlled‐release mechanism for silver, in this way improving biocompatibility, reducing inflammation, and stimulating bone growth. Notably, Ag─Ga suspensions can be conveniently deposited by spray‐coating on a range of devices and material surfaces, effectively eliminating pathogenic bacteria with efficacy comparable to that of silver ions. In vivo studies in rat models affirm the antibacterial capabilities, especially against methicillin‐resistant Staphylococcus aureus and Escherichia coli, when placed on implants such as titanium rods and magnesium discs. Furthermore, Ag─Ga promotes bone matrix formation and collagen growth without eliciting an inflammatory response, indicating a major promise for coatings on a wide variety of biomedical devices and materials. [ABSTRACT FROM AUTHOR]

Aloe perryi has been studied and possesses several activities, including antibacterial, antiparasitic, and anticancer properties. In this study, A. perryi was used as a reducing agent of silver ions into silver nanoparticles. Aloe perryi–silver nanoparticles (APS‐NPs) were characterized and evaluated using characterization techniques. However, the antioxidative, antibacterial, and anticancer assays were studied to evaluate the pharmacological activities of APS‐NPs. APS‐NPs were developed and changed to dark brown and the maximum absorption was 442 nm. SEM (5–583 nm), TEM (4–110 nm), XRD (21.84 nm), and zeta potential analysis (63.39 nm) revealed that the APS‐NPs were nano‐sized, and the APS‐NPs had a cubic crystalline structure, according to the XRD results. FTIR analysis suggested that functional groups of A. perryi metabolites were involved in forming APS‐NPs. The zeta potential indicated that the APS‐NPs were negatively charged (−32 mV), suggesting good stability. APS‐NPs showed significant antioxidative stress activity by reducing DPPH‐free radicles in a dose‐dependent manner. APS‐NPs‐induced antibacterial effect against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Acinetobacter baumannii (A. baumannii). APS‐NPs reduced the cell viability and cell migration of the human colon tumor cell line (HCT 116) compared with controls, indicating that APS‐NPs could play a role in reducing metastasis and inducing cell apoptosis against colon cancer. In conclusion, the nanoparticle synthesis from A. perryi extract demonstrated excellent antioxidant, antibacterial, and anticancer activities, thus suggesting that our APS‐NPs have the potential to be used as antioxidative and antibacterial in food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Prosthetic joint infection represents a problem that worsens the patient's quality of life and produces an economic impact on health systems. We report the anodization of Ti6Al4V coupons obtained by electron beam melting to produce a nanostructured surface. Anodization at 10 V produced TiO2 nanopores with a diameter in the range of 15–20 nm. Thereafter, Ag nanoparticles (AgNPs) were deposited in three different ways to provide antibacterial functionality to the coatings: electrochemically, thermally, and chemically. The electrochemical method did not provide good coverage of AgNPs. At 0.1 V of synthesis potential, cubic, octahedral, and truncated octahedral Ag crystals were obtained. The thermal method provided a good distribution of AgNPs but it damaged the TiO2 nanostructure. The chemical method showed the best distribution of AgNPs over the anodized surface and preserved the anodized nanostructure. For this reason, the chemical method was selected to perform further studies. Ag+ release was monitored in simulated body fluid at 37 °C, reaching 1.86 mg Ag+/L after 42 days. The antibacterial coating showed excellent antibacterial activity and inhibited biofilm formation for Staphylococcus epidermidis RP62A and Staphylococcus aureus V329 strains (lethality > 99.9% for both bacteria and assays). [ABSTRACT FROM AUTHOR]

Magnetic solid-phase extraction (MSPE) is a highly effective method for separating metal ions from aquatic solutions, making it a popular choice for metal ion separation. This study investigated the behavior of Fe3O4@SiO2-SH core–shell composites for the adsorption and recovery of silver ions. The quality of the synthesized adsorbent was verified using XRD, FT-IR, EDS, FE-SEM, and EDAX-map analyses. Magnetic properties and surface charge changes were assessed using VSM and Zeta potential analyses. By implementing the classic OFAT method, the study evaluated the effect of various parameters on silver adsorption, such as pH, composite dosage, initial Ag+ concentration, temperature, and secondary metal ions. Results showed that the proposed composite had a high maximum adsorption capacity (112 mg/g) at pH = 6, ambient temperature, 0.1 g/L adsorbent dosage, and silver concentrations greater than 25 mg/L. The composite demonstrated good selectivity in Ag+ separation from a bimetallic solution containing silver and mercury ions. The results also showed that 1M HNO3 and 1M HCl solutions released over 78% and 70% of absorbed ions from the composite surface, respectively. However, the HCl solution enabled the precipitation of almost all desorbed Ag+, providing a selective recovery of silver ions. [ABSTRACT FROM AUTHOR]

In this work, a new two‐step process is developed by exchanging Na+ and Ag+ to create a radial GRIN infrared lens. The first step consists in introducing a high amount of silver by solid‐state ion exchange in the surrounding of the glass sample when the second one allows for controllable diffusion of Ag+ within the center of the sample by single heat treatment. Evolution of the refractive index and ∆n between the two extreme compositions of the GRIN are determined as function of the wavelength, predicting a ∆n of 1.42 × 10−1 at 10 µm. Qualitative characterization of the sample reveals the formation of a GRIN chalcogenide glass transparent in the MWIR and LWIR, presenting no detrimental crystallization of residual metallic silver on the edge of the sample. Wavefront measurement allows to quantitatively characterize the 10 mm diameter IR GRIN as a polynomial profile with a ∆n of 1.8 × 10−1 at 10.6 µm. [ABSTRACT FROM AUTHOR]

With the expansion of nanomaterials (NMs) usage, concerns about their toxicity are increasing, and the wide variety of NMs makes it difficult to assess their toxicity. Therefore, the development of a high-throughput, accurate, and certified method to evaluate the immunotoxicity of NMs is required. In this study, we assessed the immunotoxicity potential of various NMs, such as nanoparticles of silver, silica, and titanium dioxide, using the human Cell Line Activation Test (h-CLAT) at the cellular level. After exposure to silver nanoparticle dispersions, the expression levels of CD86 and CD54 increased, suggesting the activation of antigen-presenting cells (APCs) by silver nanoparticles. Quantification of silver ions eluted from silver nanoparticles and the activation of APCs by silver ions suggested that it was due to the release of silver ions. Silica nanoparticles also increased the expression of CD86 and/or CD54, and their activation ability correlated with the synthesis methods and hydrodynamic diameters. The ability of titanium dioxide to activate APCs differed depending on the crystal type and hydrodynamic diameter. These results suggest a potential method to evaluate the immunotoxicity potential of various NMs based on their ability to activate APCs using human monocytic THP-1 cells. This method will be valuable in assessing the immunotoxicity potential and elucidating the immunotoxic mechanisms of NMs. [ABSTRACT FROM AUTHOR]

Atomically precise low‐nuclearity (n<10) silver nanoclusters (AgNCs) have garnered significant interest due to their size‐dependent optical properties and diverse applications. However, their synthesis has remained challenging, primarily due to their inherent instability. The present study introduces a new feasible approach for clustering silver ions utilizing highly negative and redox‐inert polyoxoniobates (PONbs) as all‐inorganic ligands. This strategy not only enables the creation of novel Ag‐PONb composite nanoclusters but also facilitates the synthesis of stable low‐nuclearity AgNCs. Using this method, we have successfully synthesized a small octanuclear rhombic [Ag8]6+ AgNC stabilized by six highly negative [LiNb27O75]14− polyoxoanions. This marks the first PONb‐protected superatomic AgNC, designated as {Ag8@(LiNb27O75)6} (Ag8@Nb162), with an aesthetically spherical core–shell structure. The crystalline Ag8@Nb162 is stable under ambient conditions, What's more, it is water‐soluble and able to maintain its molecular cluster structure intact in water. Further, the stable small [Ag8]6+ AgNC has interesting temperature‐ and pH‐dependent reversible fluorescence response, based on which a multiple optical encryption mode for anti‐counterfeit technology was demonstrated. This work offers a promising avenue for the synthesis of fascinating and stable PONb‐protected AgNCs and sheds light on the development of new‐type optical functional materials. [ABSTRACT FROM AUTHOR]

Hydrotalcite–silver (HT−Ag) nanoparticles have been involved in various daily crucial applications, such as antibacterial, photocatalytic, adsorption, etc. There are many approaches to synthesizing silver nanoparticles (AgNPs) decorated on hydrotalcite (HT) surface and the most used approach is using a strong reducing agent. Thus, affordable but effective "green" reducing agents – Syzygium nervosum leaf extract, are taken into account in this work to solve several issues related to chemical reducing agents. This work aimed to assess the effect of Syzygium nervosum leaf extract as a reducing agent for green synthesis of AgNPs on HT through an optimizing process using response surface methodology (RSM) and the Box‐Benken model. The optimal conditions for the synthesis of AgNPs on HT include a reaction time of 6.15 hours, a reaction temperature of 50 °C, and the ratio of diluted Syzygium nervosum leaf extract to reduce AgNO3 of 50.37 mL/mg. Under the optimal conditions, the yield of the reduction reaction reached 77.54 %, close to the theoretical value of 76.97 %. The optimization model was suitable for the experiment data. Besides, the morphology, density, and characteristics of AgNPs on the surface of HT layers have been determined by using Ultraviolet‐visible spectroscopy, Field emission scanning electron microscopy (FESEM), High‐resolution transmission electron microscopy (HR‐TEM), selected area diffraction, X‐ray diffraction, Dynamic light scattering (DLS), Infrared (IR) spectroscopy, Fluorescence emission spectroscopy (FE), Brunauer‐Emmett‐Teller (BET) methods. The spherical AgNPs were synthesized successfully on the surface of HT with the average particle size of 13.0±1.1 nm. Interestingly, HT−Ag hybrid materials can inhibit strongly the growth of E. coli, S. aureus as well as two antibiotic resistance bacterial strains, P. stutzeri B27, and antibiotic resistance E. coli. Especially, the antibacterial activity quantification and durability of the HT−Ag hybrid materials were also tested. Overall, the HT−Ag hybrid materials are very promising for application in material science and biomedicine fields. [ABSTRACT FROM AUTHOR]

Silver(I) complexes with proline and hydroxyproline were synthesized and structurally characterized and crystal structure analysis shows that the formulas of the compounds are {[Ag2(Pro)2(NO3)]NO3}n (AgPro) (Pro = L -proline) and {[Ag2(Hyp)2(NO3)]NO3}n (AgHyp) (Hyp = trans-4-hydroxy- L -proline). Both complexes crystallize in the monoclinic lattice with space group P21 with a carboxylate bidentate-bridging coordination mode of the organic ligands Pro and Hyp (with NH2+ and COO− groups in zwitterionic form). Both complexes have a distorted seesaw (C2v) geometry around one silver(I) ion with τ4 values of 58% (AgPro) and 51% (AgHyp). Moreover, the results of spectral and thermal analyses correlate with the structural ones. 1H and 13C NMR spectra confirm the complexes species' presence in the DMSO biological testing medium and their stability in the time range of the bioassays. In addition, molar conductivity measurements indicate complexes' behaviour like 1 : 1 electrolytes. Both complexes showed higher or the same antibacterial activity against Bacillus cereus, Pseudomonas aeruginosa and Staphylococcus aureus as AgNO3 (MIC = 0.063 mM) and higher than silver(I) sulfadiazine (AgSD) (MIC > 0.5 mM) against Pseudomonas aeruginosa. In addition, complex AgPro exerted a strong cytotoxic effect against the tested MDA-MB-231 and Jurkat cancer cell lines (IC50 values equal to 3.7 and 3.0 μM, respectively) compared with AgNO3 (IC50 = 6.1 (5.7) μM) and even significantly higher selectivity than cisplatin (cisPt) against MDA-MB-231 cancer cell lines (SI = 3.05 (AgPro); 1.16 (cisPt), SI – selectivity index). The binding constants and the number of binding sites (n) of AgPro and AgHyp complexes with bovine serum albumin (BSA) were determined at four different temperatures, and the zeta potential of BSA in the presence of silver(I) complexes was also measured. The in ovo method shows the safety of the topical and intravenous application of AgPro and AgHyp. Moreover, the complexes' bioavailability was verified by lipophilicity evaluation from the experimental and theoretical points of view. [ABSTRACT FROM AUTHOR]

There has been increasing interest in the use of squaraines with different physicochemical properties. However, their applications in nanoplasmonics are limited. For that, detailed information on the interactions of squaraines with plasmonic nanostructures is required. In this work, we have studied the adsorption of the squaraine cis‐dicyanomethylene squarate (CDSQ) on the surface of Ag nanoparticles (AgNP). We have combined normal Raman, surface‐enhanced Raman scattering (SERS), and DFT calculations to get insights into the configuration of its adsorption. DFT calculations have been carried out using simplified models of different adsorption geometries for comparison with the results of the SERS experiments. A comparison between the relative intensities of the normal Raman and SERS spectra indicates that CDSQ is adsorbed perpendicular to the AgNP surface. The predicted spectra suggest that CDSQ is chemically adsorbed on the silver surface through one of its N atoms. [ABSTRACT FROM AUTHOR]

To develop a novel glass ionomer cement (NGIC) with enhanced mechanical and chemical properties and assess its biocompatibility, mechanical strength, and ion release. Nanosilver doped bioactive glass (NanoAg BAG) was synthesized by sol-gel method and characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy and transmission electron microscopy. The NanoAg BAG, together with poly(vinylphosphonic acid) (PVPA), alumino-fluorosilicate glass and poly-acrylic acid were used to synthesize NGIC. The optimal PVPA concentration for NGIC was determined by PVPA modified GIC's biocompatibility and mechanical properties and used to prepare NGIC specimens. NGIC specimens with NanoAg BAG at 0%, 1%, 2%, and 5% were allocated into Groups NGIC0, NGIC1, NGIC2, and NGIC5, respectively. The biocompatibility, surface morphology, elemental composition, surface topography, chemical properties, compressive strength, diametral tensile strength, and ion release of the NGIC were assessed. A conventional glass ionomer cement (GIC) was used as a control. A granular BAG with nano silver particles attached on its surface were found, indicating the successful synthesis of NanoAg BAG. PVPA at 10% presented the best effect in enhancing the biocompatibility and mechanical properties of PVPA modified GIC and was used to prepare NGIC specimens. NGIC1 showed similar biocompatibility, surface morphology and topography to GIC. Chemical properties results showed that NGICs showed the same adsorption peaks to GIC. The compressive strength (mean±SD in MPa) was 168.1 ± 29.7, 205.5 ± 29.5, 221.8 ± 46.8, 216.6 ± 59.3 and 167.7 ± 36.4, and the diametral tensile strength (mean±SD in MPa) was 14.1 ± 1.7, 18.3 ± 4.9, 21.2 ± 2.2, 17.2 ± 3.8 and 13.3 ± 3.3 for GIC, NGIC0, NGIC1, NGIC2 and NGIC5 respectively. NIGC0, NGIC1 and NGIC2 showed higher compressive and diametral tensile strength than GIC (p < 0.01). NGIC2 and NGIC5 showed higher release of fluoride, calcium, phosphate and silver ion than GIC and NGIC0 (p < 0.05). A biocompatible NGIC with enhanced mechanical properties were developed. It presented enhanced fluoride, calcium, phosphate and silver ion release compared to conventional GIC. [ABSTRACT FROM AUTHOR]

In this work, AgNPs were synthesized using an anthocyanin extract from Peruvian purple potato INIA 328—Kulli papa. The anthocyanin extract was obtained through a conventional extraction with acidified ethanolic aqueous solvent. This extract acted as both a reducing and stabilizing agent for the reduction of silver ions. Optimization of synthesis parameters, including pH, reaction time, and silver nitrate (AgNO3) concentration, led to the optimal formation of AgNPs at pH 10, with a reaction time of 30 min and an AgNO3 concentration of 5 mM. Characterization techniques such as X-ray diffraction (XRD) and dynamic light scattering (DLS) revealed that the AgNPs had a crystallite size of 9.42 nm and a hydrodynamic diameter of 21.6 nm, with a zeta potential of −42.03 mV, indicating favorable colloidal stability. Fourier Transform Infrared (FTIR) analysis confirmed the presence of anthocyanin functional groups on the surface of the AgNPs, contributing to their stability. Furthermore, the bacterial activity of the AgNPs was evaluated by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). For E. coli, the MIC was 0.5 mM (0.05 mg/mL) and the MBC was 4.5 mM (0.49 mg/mL). Similarly, for S. aureus, the MIC was 0.5 mM (0.05 mg/mL) and the MBC was 4.0 mM (0.43 mg/mL). These results highlight the potential benefits of AgNPs synthesized from Peruvian purple potato anthocyanin extract, both in biomedical and environmental contexts. [ABSTRACT FROM AUTHOR]

As a new structural motif, an interesting 3D energetic metal – framework of silver ions and 3,4-diaminofurazan, [Ag+(daf)NO3−]n, is successfully synthesized and the structure is determined by single-crystal X-ray diffraction. The effects of hydrogen bond, coordination bond, adsorption and filling interactions make this compound have a high density (2.694 g·cm−3 at 293 K). The calculated detonation velocity and the sensitivities are all comparable with trinitrotoluene (TNT). The onset decomposition temperature is equal to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), state-of-the-art explosive. This framework provides a potential superiority of E-MOFs for energetic materials. [ABSTRACT FROM AUTHOR]

Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-C3N4 nanosheets, silver ion (Ag+) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag+ generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-C3N4 nanosheets and oxOPD emit fluorescence at 440 nm (F440) and 560 nm (F560), respectively. Additionally, oxOPD exhibits quenching ability towards g-C3N4 nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag+ intensively, and consequently diminish the amount of free Ag+ in the testing system. Less amount of free Ag+ leads to less production of oxOPD, resulting in less fluorescence quenching towards g-C3N4 nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-C3N4 nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F440/F560) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA420) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L−1 for ratiometric fluorescence mode and 0.7 U L−1 for colorimetric mode. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of Triton X-100 (TX-100) reducing the Ag+-resistance of Enterococcus faecalis (E. faecalis), and evaluate the antibacterial effect of TX-100 + Ag+ against the induced Ag+-resistant E. faecalis (AREf). The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of AgNO3 against E. faecalis with/without TX-100 were determined to verify the enhanced antibacterial activity. Transmission electron microscopy (TEM) was used to observe the morphological changes of E. faecalis after treatment. The intra- and extracellular concentration of Ag+ in treated E. faecalis was evaluated using inductively coupled plasma mass spectrometer (ICP-MS). The changes in cell membrane potential and integrity of treated E. faecalis were also observed using the flow cytometer. Moreover, AREf was induced through continuous exposure to sub-MIC of Ag+ and the antibacterial effect of TX-100 + Ag+ on AREf was further evaluated. The addition of 0.04% TX-100 showed maximal enhanced antibacterial effect of Ag+ against E. faecalis. The TEM and ICP-MS results demonstrated that TX-100 could facilitate Ag+ to enter E. faecalis through changing the membrane structure and integrity. Flow cytometry further showed the effect of TX-100 on membrane potential and permeability of E. faecalis. In addition, the enhanced antibacterial effect of TX-100 + Ag+ was also confirmed on induced AREf. TX-100 can facilitate Ag+ to enter E. faecalis through disrupting the membrane structure and changing the membrane potential and permeability, thus reducing the Ag+-resistance of E. faecalis and enhancing the antibacterial effect against either normal E. faecalis or induced AREf. [ABSTRACT FROM AUTHOR]

Metal-mediated base pairs in DNA double helix molecules open up broad opportunities for biosensors based on DNA clusters with silver due to their low toxicity and applicability in drug design. Despite intensive experimental and computational research, molecular mechanisms of stabilization of a double helix by silver-mediated base pairs are mainly unknown. We conducted all-atom molecular dynamics simulations of a dodecameric DNA double helix (sequence 5′-TAGGTCAATACT-3′-3′ATCCACTTATGA-5′) with either cytosine–cytosine or cytosine–Ag+–cytosine mismatch in the center of the duplex. We extended the previously proposed set of interaction parameters for a silver ion in the silver-mediated pair in order to allow for its dissociation. With this new potential, we studied how the addition of a silver ion could stabilize a DNA double helix containing a single cytosine–cytosine mismatch. In particular, we found out that the helix with cytosine–Ag+–cytosine mismatch has a greater melting temperature than the helix with cytosine–cytosine one. This stabilization effect of the silver ion is in qualitative agreement with experimental data. The central region of the duplex with cytosine–Ag+–cytosine mismatch (unlike with cytosine–cytosine mismatch) is stable enough to prevent bubble formation at moderate temperatures during melting. The results of this simulation can be used to devise novel metal-mediated DNA structures. [ABSTRACT FROM AUTHOR]

Background: Over the past two decades, Silver Nanoparticles (AgNPs) have demonstrated a wide range of antioxidant and anticancer properties. Vinca alkaloid exhibits the anticancer efficacy by direct metaphase arrest of cell division. Aim: The present study is to develop a green synthesis method for producing silver nanoparticles using vinca, the antioxidant and anticancer potential was assessed using A549 cells. Materials and Methods: The synthesized AgNPs were analyzed using Fourier Transform Infrared (FTIR) analysis, UV-visible spectrophotometer (UV), Scanning Electron Microscope (SEM) and Spectra Max i3X energy-dispersive X-ray (XRD) Spectroscopy to determine their physico-chemical and morphological characteristics. Results and Discussion: The FTIR spectrum of vinca AgNPs exhibited absorption bands at 692 cm-1, 684 cm-1, 611 cm-1, 592 cm-1, 578 cm-1, 554 cm-1, 548 cm-1, 539 cm-1 and 526 cm-1, indicating the presence of silver ion bounded nanoparticles derived from Vinca leaf. These findings suggest that vinca-coated AgNPs possess multiple functions that contribute to their stability. XRD data analysis revealed Bragg's reflections in the XRD pattern (2θ) at 24.75, 31.59, 37.56, 53.01, 64.93 and 76.27, confirming the crystalline nature of the green synthesized AgNPs. Elemental analysis was conducted to determine the elemental composition of the sample, which indicated that approximately 60% of the prepared nanoparticles were bound with silver ions, supporting the formulation. Antioxidant studies were performed using the DPPH assay at different concentrations of AgNPs, while cell-based cytotoxic assays were conducted using different concentrations of AgNO3. Conclusion: The results demonstrated that the nanoparticles inhibited the proliferation of A549 cells and reduced cellular motility, indicating their promising anticancer efficacy. [ABSTRACT FROM AUTHOR]

By using dielectric spectroscopy in a broad range of temperatures and frequencies, we have investigated dipolar relaxations, the dc conductivity, and the possible occurrence of polar order in AgCN. The conductivity contributions dominate the dielectric response at elevated temperatures and low frequencies, most likely arising from the mobility of the small silver ions. In addition, we observe the dipolar relaxation dynamics of the dumbbell-shaped CN− ions, whose temperature dependence follows the Arrhenius behavior with a hindering barrier of 0.59 eV (57 kJ/mol). It correlates well with a systematic development of the relaxation dynamics with the cation radius, previously observed in various alkali cyanides. By comparison with the latter, we conclude that AgCN does not exhibit a plastic high-temperature phase with free rotation of the cyanide ions. Instead, our results indicate that a phase with quadrupolar order, revealing dipolar head-to-tail disorder of the CN− ions, exists at elevated temperatures up to the decomposition temperature, which crosses over to long-range polar order of the CN dipole moments below about 475 K. Dipole ordering was also reported for NaCN and KCN, and a comparison with these systems suggests a critical relaxation rate of 105–107 Hz, marking the onset of dipolar order in the cyanides. The detected relaxation dynamics in this order–disorder type polar state points to glasslike freezing below about 195 K of a fraction of non-ordered CN dipoles. [ABSTRACT FROM AUTHOR]

Herein, silver ions modified α-Fe2O3 (Ag: α-Fe2O3) nanoparticles were synthesized using a sol-gel auto-combustion method comprising of dual phase i.e. trigonal structure of α-Fe2O3 and FCC structure of Ag. The refinement results verified the existence of both the phase with R-3c: R s and Fm-3 m space group. Transmission Electron Microscopy (TEM) showed the crystallite size around 34.24 ± 2.00 nm. The percentage of Ag0 and Ag+ verified through X-ray Photoelectron Spectroscopy (XPS) clearly indicate that around 74% of the Ag present is in the metallic form. The cyclic voltammetry showed that the Csp of the Ag: α-Fe2O3 NPs modified electrode is 132 Fg − 1 and 100 Fg − 1 when recorded at a scan rate of 50 mVs− 1 and 75 mVs− 1, respectively. The Zones of Inhibition (ZOI) against bacterial strains generated by utilizing Ag: α-Fe2O3 NPs are clearly showed the ZOI of 19 ± 1 mm against Bacillus subtilis. The synthesized nanoparticles exhibited higher inhibition against the bacterial strains in comparison to the standard antibiotic ampicillin. Further, cell viability analysis suggested to use a concentration of 9 to 12 µg/ml for Ag: α-Fe2O3in invitro experiments. [ABSTRACT FROM AUTHOR]

In this paper the silver ions in a silver nitrate solution were reduced to the Ag element by silk sericin (SS); then, N-isopropylacrylamide (NIPAAm) was added into the mixed solution of SS and silver nitrate to form the bifunctional SS/NIPAAm-Ag3 hydrogel with interpenetrating network structure with N,N-methylenebisacrylamide (BIS) as a cross-linking agent, ammonium persulfate (APS) as a initiator and N, N, N', N-tetramethylethylenediamine (TEMED) as a co-initiator. SEM showed that the SS/NIPAAm-Ag3 hydrogel had a regular honeycomb structure and high porosity. It was confirmed by DSC that the SS/NIPAAm-Ag3 hydrogel exhibited temperature sensitivity, and its Lower Critical Solution Temperature (LCST) was about 35 °C. The swelling degree of the SS/NIPAAm-Ag3 hydrogel was obviously higher than that of SS/NIPAAm hydrogel at 25 °C and 37 °C. The time required for deswelling equilibrium was shortened by 2 h compared with SS/NIPAAm hydrogel, showing that the introduction of a certain amount of nano-Ag could give hydrogel excellent swelling and deswelling properties. The bacteriostatic rates against Esherichia coli (E.coli) and Staphylococcus aureus (S. aureus) reached 99.8% and 93.38%, respectively. A cytotoxicity test proved that SS/NIPAAm-Ag3 hydrogel had no adverse effects on the human cell health. The development of this temperature-sensitive and antibacterial hydrogel provides a new possibility for the preparation of hydrogel medical dressing. [ABSTRACT FROM AUTHOR]

This report demonstrates the synthesis of a trihybrid system (PBI-NP-GO) consisting of perylene bisimide appended peptide (PBI-UW) nanofibers, silver nanoparticles (PBI-AgNP), and graphene oxide (GO) nanosheet. Tryptophan-containing PBI molecules in an aqueous medium can reduce silver ions into silver nanoparticles in the presence of sunlight to form a dihybrid system consisting of nanofibers and nanoparticles; the addition of GO into the dihybrid system ultimately leads to the formation of the trihybrid system. The trihybrid system was thoroughly characterized by various spectroscopic and microscopic techniques, such as ultraviolet-visible (UV-vis), Fourier transform-infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), RAMAN, and field emission transmission electron microscopy (FEG-TEM). The so-formed trihybrid system was successfully utilized as a potential photocatalyst for the reduction of carcinogenic Cr(VI) to non-toxic Cr(III) under irradiation with blue LED light. An almost complete reduction of Cr(VI) was achieved within 30 minutes of irradiation. Moreover, good photo-switching behaviour was observed with the highest photocurrent gain of 5.11 (Ion/Ioff) compared to PBI-AgNP (dihybrid) and PBI-UW, where Ion/Ioff values of 3.92 and 2.31, respectively, were obtained. The photocatalytic activity and photo-switching behaviour of the trihybrid system are due to efficient photo-induced charge separation. [ABSTRACT FROM AUTHOR]

Gallium ion incorporation into silver indium gallium sulfide nanocrystals is investigated by various methods, including photoluminescence (PL) and X-ray photoelectron spectroscopy. The ZnS shell-growth enhances a PL quantum yield of up to 16%, with which the quantum dot light-emitting diode was successfully fabricated. [ABSTRACT FROM AUTHOR]

This study ventures into unexplored realms by investigating the combined efficacy of aminoglycosides (amikacin (AMI), gentamicin (GEN), kanamycin (KAN), streptomycin (STR), and tobramycin (TOB)) and silver nanoparticles (AgNPs) against pathogenic E. coli, offering a novel approach to combating antibiotic resistance. A noticeable transformation in color from a soft yellow to a rich brown marked the transition of silver ions to AgNPs, a process visually captured over 42 h. Morphological investigations showcased untreated E. coli cells retaining their natural rod shape, contrasted by AgNP treated cells that displayed considerable structural damage, signifying compromised cellular integrity. Antibacterial experiments, involving MIC and MBC tests, unveiled an increased effectiveness of antibiotics when paired with AgNPs, demonstrating a remarkable synergistic relationship. Time-kill assays provided a bacterial reductions, highlighting the boosted antibacterial action resulting from the combined application of AgNPs and antibiotics. The combination of TOB with AgNPs displayed the most substantial biofilm reduction, reaching at 19.87%. Fascinatingly, the armA gene was observed in bacterial cultures exposed to a TOB (2MIC), but its non-detection in cultures treated with a mix of 2MIC TOB and AgNP stood out as particularly noteworthy. This research unveiled a crucial finding where the antibacterial effectiveness of aminoglycosides consistently improved when combined with AgNPs. The findings suggested a promising direction for further research into the synergistic effects of antibiotics and nanoparticle adjuncts. Understanding the underlying mechanisms of this interaction could provide valuable insights into combating bacterial resistance, particularly in strains that are resistant to conventional antibiotic treatments. [ABSTRACT FROM AUTHOR]

Precious metal nanoparticles, especially Ag-based nanoparticles due to their strong surface plasma effect and excellent catalytic performance, have been widely applied in environmental remediation and detection of heavy metal ions in aqueous solution. In this study, first, bimetallic Ag/Co nanoparticles (Ag/Co NPs) modified by sodium citrate were synthesized by chemical reduction method. Second, bimetallic Ag/Co NPs were used as colorimetric probe for detecting Cr 3 + and Fe 3 + in aqueous solution simultaneously for the first time. The results showed that the probe had high specificity towards Cr 3 + and Fe 3 + among the tested metal ions. When Cr 3 + was mixed with Ag/Co NPs, the solution quickly changed from yellow to pink, meanwhile, the UV–Vis absorption intensity declined at 400 nm and a new prominent absorption band was formed at 530 nm. While Fe 3 + was mixed with Ag/Co NPs, the solution quickly changed from yellow to nearly colorless. The linear relationship between absorbance of bimetallic Ag/Co NPs at 400 nm and −log of Cr 3 + concentration is 1 nM to 10 μ M, which y = 0. 0 0 8 4 x + 1. 5 0 1 2 and R 2 = 0. 9 8 5 5. The limit of detection (LOD) for this study was 1.14 nM. Similar to Cr 3 + , the LOD for Fe 3 + was calculated 16.3 μ M. In addition, the catalytic performance of bimetallic Ag/Co NPs was evaluated by methylene blue (MB) in the presence of H2O2. The catalytic degradation efficiency of bimetallic Ag/Co NPs was about 4.8 times greater than monometallic Ag NPs, confirming Ag and Co NPs had obviously synergistic effect. Therefore, this result made bimetallic Ag/Co NPs had potential application in the field of environmental remediation. Bimetallic Ag/Co nanoparticles (NPs) modified by sodium citrate were synthesized by chemical reduction method. The prepared Ag/Co NPs were used as a colorimetric probe for detecting Cr3+ and Fe3+ in aqueous solution simultaneously for the first time. Furthermore, the catalytic performance of bimetallic Ag/Co NPs was evaluated by methylene blue in the presence of H2O2. The catalytic degradation efficency of bimetallic Ag/Co NPs was 4.8 times greater than monometallic Ag NPs, confirming that Ag and Co NPs have a synergistic effect. [ABSTRACT FROM AUTHOR]

Background: Zeolite can release antimicrobial silver ions in a targeted and controlled manner for an extended time, selectively inhibiting the growth of pathogenic oral bacteria when added to dental materials. The objective of this study was to investigate the effect of the addition of zeolite to silver-reinforced glass ionomer cement on the release of silver ions over time. Methods: Five concentrations of silver–zeolite (0%, 0.5%, 1%, 2%, 4% wt) were incorporated into silver-reinforced GIC in the form of 10 mm × 2 mm circular disks (n = 5). The disks were incubated in deionized water at 37 °C and ion release from the samples was measured at 1, 2, 7, and 30 days after immersion by inductively coupled atomic emission spectroscopy. Results: Incorporating silver–zeolite increased silver ion release from silver-reinforced GIC disks compared to the control disks (p < 0.05), while incorporating zeolite alone had no effect. Higher concentrations of added silver–zeolite resulted in increased silver ion release. Sustained silver ion release was observed for up to 30 days. Conclusion: Adding silver–zeolite to silver-reinforced GIC may enhance its extended antibacterial effect in the oral cavity. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic resistance, caused by the improper use of antibiotics, is a significant challenge in combating infectious diseases, leading to millions of annual fatalities. The occurrence of antimicrobial side effects catalyzes the investigation of novel antimicrobial compounds and sources of drugs. Consequently, the research on biological activity that is conducted on plants, plant extracts, and compounds that are produced from plant components is of utmost significance. In this study, CtAC/MNPs were obtained by the reaction of activated carbon (AC) obtained from the fruits of the Celtis tournefortii (Ct) plant and magnetic nanoparticles (MNPs), and a CtAC/MNPs-Ag nanocomposite was synthesized by the reduction in silver ions added to the reaction. The synthesized CtAC/MNPs and CtAC/MNPs-Ag nanocomposites were analyzed spectroscopically (FTIR, XRD), microscopically (SEM, EDX), optically (DLS), electrochemically (zeta potential) and magnetically (VSM). The antibacterial activities of CtAC/MNPs and CtAC/MNPs-Ag nanocomposites against S. aureus and E. coli were investigated by microdilution method using minimal inhibitory concentration (MIC) and disk diffusion methods. Antioxidant activity study, including total phenolic content and DPPH and cuprac assays, revealed the remarkable effect of the CtAC/MNPs-Ag nanocomposite. This study has the advantages of obtaining CtAC/MNPs and CtAC/MNPs-Ag nanocomposites in a short time without requiring energy, and most importantly, the reaction takes place without using any toxic substances. In addition, according to the data obtained in the study, the CtAC/MNPs-Ag nanocomposite is thought to shed light on biomedical research. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic-resistant bacteria necessitates the development of novel, sustainable, and biocompatible antibacterial agents. This study addresses cytotoxicity and environmental concerns associated with traditional silver nanoparticles (AgNPs) by exploring lignin, a readily available and renewable biopolymer, as a platform for AgNPs. We present a novel one-pot synthesis method for lignin-based AgNPs (AgNPs@AL) nanocomposites, achieving rapid synthesis within 5 min. This method utilizes various organic solvents, demonstrating remarkable adaptability to a wide range of lignin-dissolving systems. Characterization reveals uniform AgNP size distribution and morphology influenced by the chosen solvent. This adaptability suggests the potential for incorporating lignin-loaded antibacterial drugs alongside AgNPs, enabling combined therapy in a single nanocomposite. Antibacterial assays demonstrate exceptional efficacy against both Gram-negative and Gram-positive bacteria, with gamma-valerolactone (GVL)-assisted synthesized AgNPs exhibiting the most potent effect. Mechanistic studies suggest a combination of factors contributes to the antibacterial activity, including direct membrane damage caused by AgNPs and sustained silver ion release, ultimately leading to bacterial cell death. This work presents a straightforward, adaptable, and rapid approach for synthesizing biocompatible AgNPs@AL nanocomposites with outstanding antibacterial activity. These findings offer a promising and sustainable alternative to traditional antibiotics, contributing to the fight against antibiotic resistance while minimizing environmental impact. [ABSTRACT FROM AUTHOR]

[Display omitted] As a noble metal with extremely high economic benefits, the recovery of silver ions has attracted a particular deal of attention. However, it is a challenge to recover silver ions efficiently and selectively from aqueous solutions. In this research, the novel metal–organic frameworks (MOFs) adsorbent (Zr-DPHT) is prepared for the highly efficient and selective recovery of silver ions from wastewater. Experimental findings reveal that Zr-DPHT's adsorption of Ag(I) constitutes an endothermic process, with an optimal pH of 5 and exhibits a maximum adsorption capacity of 268.3 mg·g−1. Isotherm studies show that the adsorption of Ag(I) by Zr-DPHT is mainly monolayer chemical adsorption. Kinetic studies indicate that the internal diffusion of Ag(I) in Zr-DPHT may be the rate-limiting step. The mechanism for Ag(I) adsorption on Zr-DPHT involves electrostatic interactions and chelation. In competitive adsorption, Ag(I) has the largest partition coefficient (9.64 mL·mg−1), indicating a strong interaction between Zr-DPHT and Ag(I). It is proven in the adsorption–desorption cycle experiments that Zr-DPHT has good regeneration performance. The research results indicate that Zr-DPHT can serve as a potential adsorbent for efficiently and selectively capturing Ag(I), providing a new direction for MOFs in the recycling field of precious metals. [ABSTRACT FROM AUTHOR]

Glycine silver nitrate (GSN) and fully deuterated GSN (FDGSN) form two isotopic polymorphs. The effect of full deuteration brought about the isotopic polymorph of GSN. In order to study the effect of partial deuteration on isotopic polymorphs, crystals of C-deuterated GSN (CDGSN) and N-deuterated GSN (NDGSN) were grown. The crystal structure of C deuteration was similar to FDGSN forming 2-dimensional polymeric structures extended along the c-axis. In CDGSN, the silver ion is mononuclear similar to that in FDGSN with no Ag-Ag coordination. N deuteration had similar crystal structure to that of GSN. The nitrate ion, the silver ion and the zwitterionic glycine form a three-dimensional network unlike the case in CDGSN. The silver ion is binuclear with Ag-Ag coordination similar to that in GSN. In both crystal structures, the silver ion has an oxidation state of +1. The Hirshfeld surface analysis of all the above structures was carried out using the X-ray data. The globularity parameter is similar in all the structures. For the entire complex, it is observed that FDGSN and CDGSN have similar values, which are lower than that of GSN and NDSN. The asphericity for the entire complex in the case of NDGSN and GSN is close to 0 indicating the isotropic nature whereas for FDGSN and CDGSN, it is near 0.36 indicating oblate nature. NDGSN and GSN have higher Ag···O interactions compared to that of CDGSN and FDGSN. NDGSN and GSN have Ag···Ag interaction, which is totally absent in CDGSN and FDGSN. Raman measurements showed the partial deuteration of the compounds. The lattice modes of GSN and NDGSN are similar, and FDGSN and CDGSN are similar. The C deuteration changes the coordination of the silver. In FDGSN and CDGSN, Ag ion coordinates to the hydrogen which is covalently bonded to carbon of zwitterionic glycine whereas in NDGSN and GSN, this coordination of Ag ion with hydrogen is absent. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to determine the fluoride (F) and silver (Ag) ions levels in the saliva and urine of healthy children after silver diamine fluoride (SDF) application on dental carious lesions. Methods: Sixty children (4–6 years with ≥ 3 caries lesions) were recruited from the outpatient department of Pediatric Dentistry. From each child, 3 ml unstimulated saliva samples were collected at baseline, one hour, and 24 h after SDF application. Similarly, 3 ml urine samples were collected prior to and after 24 h of SDF application. F and Ag ion concentrations were determined by fluoride ion-selective electrode (ISE) and inductively coupled plasma mass spectrometry (ICPMS), respectively. Results: The mean ± standard deviation (SD) baseline, 1-h, and 24-h salivary F concentrations (ppm) were 0.07 ± 0.07, 0.93 ± 0.48, and 0.19 ± 0.19, respectively, while the mean baseline and 24-h urinary F concentrations (ppm) were 0.33 ± 0.20 ppm and 0.43 ± 0.25 ppm, respectively. The mean baseline, 1-h, and 24-h salivary Ag concentrations (ppb) were 4.22 ± 3.15, 4198 ± 350, and 56.93 ± 37, respectively. The mean baseline and 24-h urinary Ag concentrations (ppb) were 2.80 ± 2.93 ppb and 4.72 ± 4.0 ppb, respectively. There were statistically elevated F and Ag ion concentrations at 1 h and 24 h after SDF application as compared to the baseline. Conclusion: Salivary and urinary F and Ag ions concentrations elevated significantly at 24 h following SDF applications in children. A significant high recovery of these ions in urine indicates minimal systemic absorption, thus intermittent topical application of 38% SDF has a minimal risk of toxicity. [ABSTRACT FROM AUTHOR]

The conventional three-step adhesive system is composed of an etchant, a primer, and a bonding resin. Japanese manufacturers focused on simplifying the etching and priming procedures, resulting in a one-step process referred to as "self-etching". Currently, a universal adhesive system and a universal-shade composite are trending. Morphological changes at the interface of the bonded specimens following an artificial acid-base challenge have been observed under SEM and TEM. A new layer is created beneath the hybrid layer, which is referred to as the "acid-base resistant zone (ABRZ)". With the increasing number of older adults and better teeth retention in the elderly population, the prevention and treatment of root caries are becoming increasingly important. 38% silver diamine fluoride (SDF, Saforide) contains high concentrations of silver and fluoride ions, which is very effective in preventing the progression of root dentin caries. However, the discoloration of the tooth structure is a drawback. It was reported that light exposure and demineralization of dentin accelerated its discoloration. From the evaluation of S. mutans biofilm accumulation on dentin surfaces, application of 38% SDF was the most effective to decrease the amount of biofilm attached to the dentin surface. In addition, 38% SDF has the potential to be used as a root caries indicator. From the clinical assessment, the SDF induced discoloration of the root caries lesions and provided an anti-inflammatory effect on the gingiva around the teeth affected by root caries. [ABSTRACT FROM AUTHOR]

A laundry detergent with long-term antibacterial effect was obtained by comparing the performance of six different bactericides in the formula. According to Group Standard T/ZGXX0004-2022 "Evaluation Method for Long-term Antibacterial Effect of Daily Chemical Products", the long-term antibacterial effects of six laundry detergents were tested. The test results showed that only silver ion and polyhexamethylene biguanide hydrochloride (PHMB) had a certain long-term antibacterial ability, and only PHMB could meet the requirements of the standard. By adjusting the amount of PHMB added, the long-term antibacterial effect, detergency and stability of the detergent were tested, and a non-ionic formula of long-term antibacterial laundry detergent was obtained. When the amount of PHMB added was 1.2%, the detergent had the long-term antibacterial performance required by the standard, and its detergency was good. When the amount of PHMB added was further increased to 2.0%, the laundry detergent could achieve good long-term antibacterial performance, and the detergency was significantly decreased but could still meet the requirements. In the high-and low-temperature tests, the appearance, physical and chemical indexes, detergency and long-term antibacterial performance had no significant change. [ABSTRACT FROM AUTHOR]

Tryptophan (Trp), tyrosine (Tyr), and histidine (His), known as three essential amino acids, are also precursors of vital neurotransmitters in brain nutrient metabolism. In this study, we have conducted a gas-phase study on their interactions with silver ions by a customized reflectron time-of-flight mass spectrometer combined with a magnetron sputtering source and a downstream flow tube reactor. It is unveiled that these physiological molecules are readily dissociated in the presence of Ag+ ions, giving rise to fragmentation and recombination products. Utilizing density functional theory calculations, we have clarified the reaction mechanism of the dissociative process. It is found that the silver ions facilitate the hydrogen atom transfer reaction followed by competitive Cα–Cβ and Cβ–Cγ bond dissociation. This study enriches the basic and precise properties of such neurotransmitter molecules and helps us understand similar physiological mechanisms in vivo. [ABSTRACT FROM AUTHOR]