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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]

In this work, a critical evaluation of silver ion migration at the surface of Al 0.04 Sc 0.06 Zr 0.9 O 1.95 (AlScZrO) electrolyte is explored in intermediate temperature solid oxide fuel cells (IT-SOFCs). The behaviour of silver is systematically studied at the operating conditions of silver as a cathode, anode, or sealant in IT-SOFCs. The results to those obtained at the surface of other electrolytes (gadolinia doped ceria, samaria doped ceria and yttria-stabilized zirconia) are also analysed. In the case of cathodic polarization, a thick silver deposit is formed around the electrode on the surface of the electrolyte, which may lead to the short-circuiting of the electrodes. While for the anodic polarization, oxygen bubbles are formed between the electrode and electrolyte, leading the delamination of electrode. Silver can also migrate from unpolarized parts of the cell such as sealants. Therefore, Issues related to the application of silver in IT-SOFCs should be concerned by the scientific community. [Display omitted] • Dense AlScZrO electrolyte with high ionic conductivity developed using the Pechini method. • Assessment of silver ion migration in AlScZrO electrolyte at IT-SOFCs. • Ag migration issues leading to electrode delamination and short-circuit risks, hindering its viability in SOFCs. • Ag due to migration-induced electrode instability, discouraging its use as an electrode material or sealant. [ABSTRACT FROM AUTHOR]

To address the risk of bacterial infection during the early implantation of medical titanium implants, this study designed a strontium barium titanate rod-like silver coating with piezoelectric effect. The antibacterial properties of nano-silver, the spiky structure of the rod-like array, and the piezoelectric effect were utilized to achieve rapid and continuous bactericidal effects in the early stages. The surface morphology and microstructure of the coating were analyzed, along with an examination of its phase composition and silver element distribution. Furthermore, investigations into the impact of silver loading on wetting angle and piezoelectric coefficient were conducted, as well as tests on the cumulative release of silver ions. Bacterial experiments confirmed that even after 7 days immersed in PBS, the antibacterial rate for barium strontium titanate rod-like silver coated titanium surfaces with piezoelectric effect remained at 99.99 %, slightly higher than unpolarized coatings. Finally, assessments on toxicity, proliferation, and adhesion of osteoblasts revealed excellent performance from polarized coatings. These results provide data support and a theoretical basis for studying the antibacterial effects of piezoelectricity in conjunction with other antibacterial strategies. [ABSTRACT FROM AUTHOR]

In composite materials consisting of silver particles and a polypropylene matrix, the silver must migrate to the surface of the materials in order to exert on antibacterial effect. Substrates with various crystal structures may have different interactions with the silver particles, which can significantly impact the antibacterial performance. The research described in this paper investigates the influence of silver particles on the crystallization behavior of materials with varying crystallinity capabilities by selecting various polypropylene-based plastics and elastomers (Homopolymer polypropylene (PPH-T03), random poly(propylene/ethylene) copolymers (PPR-YPR503 and PPR-P340R), polyolefin elastomers (VERSIFY3000 (POE-1) and VERSIFY3401 (POE-2)), and ethylene propylene diene monomer for polymers (EPDM4725 and EPDM4770)). The research results indicated that the silver only entered the amorphous regions of the PP rather than entering the crystal regions, where they can more easily migrate to the material surface, resulting in a higher antibacterial effect. Therefore, the antibacterial degree of PP-Ag was as high as 99.9%. Silver can enter the micro-crystals of both the random copolymer polypropylene, (PPR-YPR503, PPR-1) and the random copolymer polypropylene, (PPR-P340R, PPR-2,) with a stronger effect on PPR-2. More silver entered the micro-crystals of PPR-2, and it was difficult for the silver ions to migrate out of the crystalline regions to exhibit antibacterial properties. The antibacterial degree of PPR-1-Ag was higher than that of PPR-2-Ag (77.8% vs. 66.7%). Similarly, silver had a greater impact on the lamellar structure of the polyolefin elastomer (VERSIFY3401, POE-2) compared to the polyolefin elastomer (VERSIFY3000, POE-1). In comparison with POE-2-Ag, POE-1-Ag exhibited a higher antibacterial degree (79.6% vs. 57.4%). Research on the two types of ethylene propylene diene monomer (EPDM) composite materials indicated that EPDM-1 exhibited a lower Mooney viscosity and poorer flowability. The EPDM-1 tended to encapsulate the silver within its molecular chains, thereby impeding the migration of silver to the surface. The optical performance analysis indicated that silver antibacterial agents had little impact on the optical properties of PP-Ag, PPR-1, PPR-2, POE-1, POE-2 and the EPDMs. We suggest that this research provides theoretical guidance for selecting highly antibacterial polypropylene materials. [ABSTRACT FROM AUTHOR]

The treatment and resource utilization of solid waste and wastewater are becoming increasingly important. In this study, we propose a method to synthesize sulfur quantum dots using coked sulfur paste as raw material, which produced sulfur quantum dots with good water solubility, good dispersibility and stable luminescence performance. The synthesized sulfur quantum dots were used as a fluorescent probe for sensitively detecting low concentrations of silver ions (Ag+) based on the principle of fluorescence quenching. The detection method has a wide detection range (0–160 μM) with the lowest limit of detection of 7.1 μM and no quenching effect in the presence of 11 common ions, thus enabling the highly selective detection of silver ions. Moreover, a new method for the recovery of silver involving the strong bonding between sulfur quantum dots and silver ions was developed, i.e., even a low concentration of silver ions (under 200 μM) in industrial wastewater was converted into silver sulfide (Ag2S) and silver sulfate (Ag2SO4) for recovery. Results show that the average recovery rate reached 99.03% in the aqueous environment in the presence of five types of hetero-ions, namely, Na+, K+, Ca2+, Mg2+ and Al3+, showing both high efficiency and selectivity. This investigation realized the resourceful utilization of coked sulfur paste and provides a new pathway for the detection and recovery of low concentrations of silver in industrial wastewater. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe synthesis of catalysts has gained specific concern due to their versatile applications in particular azo dye decolorization. In the current work, metallic nanoparticles (copper and silver) were In-situ biosynthesised using Allium sativum and Chondrilla juncea extract. The obtained Allium-copper oxide and Allium-silver oxide materials were analyzed using SEM, TEM, FT-IR, TGA-DTG, SEM, TEM, and XRD techniques. Allium peels had a rough surface, with nanoparticles equally distributed over it. The crystal structure of Allium peels was altered after the addition of CuO and AgO nanoparticles. The highest residual mass values in the prepared materials indicated that the metallic nanoparticles were, in situ, formed. The prepared materials had worse thermal stability than Allium peel powders. The azo dyes, Calmagite and Naphthol Blue Black B were tested in the catalytic power of the resulting materials. The decolorization process was affected by the dye structure, amount of H2O2, dye concentration, time of reaction, and temperature of the bath. The activation energy values for Allium-CuO were 18.44 kJ mol−1 for calmagite, and 23.28 kJ mol−1 for naphthol blue black, respectively. Nevertheless, the energy values for Allium-AgO were 50.01 kJ mol−1 for calmagite and 12.44 kJ mol−1 for Naphthol blue black. The calculated low energy values for the prepared materials suggested the high efficiency of the use of these catalysts in azo dye decolorization under the change of some main experimental conditions.Chondrilla juncea was employed as a biological extract for in-situ reduction of copper and silver ions within Allium sativum peels. The resulting Allium sativum-CuO and Allium sativum -AgO materials were used as efficient catalysts for azo dye decolorization. [ABSTRACT FROM AUTHOR]

Nanoparticles synthesized from green sources have attracted great recognition in the present times, which can be ascribed to their distinctive attributes and diversified applicability. Therefore, the present study employed Ocimum basilicum seed extract to synthesize silver nanoparticles. UV–vis spectrophotometry revealed strenuous peaks for different concentrations of silver nanoparticles ranging between 400 and 430 nm. The average crystal size calculated using X-ray diffraction analysis was 6.7 nm. Energy-dispersive X-ray analysis clearly displayed the presence of silver ions in the elemental structure of the synthesized nanoparticles. The morphology of synthesized nanoparticles revealed by scanning electron microscopy was documented in terms of spherical shape surrounded by an organic layer and nanoparticle size was estimated to be in between 10 and 80 nm. The nanoparticles exhibited substantial antibacterial activity against 46 foodborne bacterial isolates and 15 clinical isolates of Klebsiella pneumoniae, with the largest inhibition zones measuring 24 and 13 mm, respectively. Minimum inhibitory concentration values ranged between 500 and 800 µl/ml for various isolates. The antibacterial effect of all antibiotics revealed considerable enhancement when combined with nanoparticles. The calculated fractional inhibitory concentration index values were < 1 validating excellent synergism between nanoparticles and all antibiotics except ciprofloxacin against the majority of bacterial isolates. Interestingly, the biogenic nanoparticles showed significant antioxidant potential with IC50 value of 165 µg/ml as well as anti-inflammatory activity with an IC50 value of 82 µg/ml. Conclusively, the seed extract of Ocimum basilicum can be prospected for the development of antibacterial silver nanoparticles against pathogenic bacteria. [ABSTRACT FROM AUTHOR]

We synthesized the silver‐decorated copper microsphere via the hydrothermal method followed by photoreduction of silver ions. Sub 100 nm Ag nanoparticles anchored on the surface of Cu microspheres enhance the electrochemical performance and the selectivity of the CO2 reduction into CH4. Incorporating Ag nanoparticles onto Cu lowers the charge transfer resistance, enhancing the catalyst's conductivity and active site and increasing the rate of CO2 reduction. The faradaic efficiency of silver nanoparticles decorated copper microsphere for methane was 70.94 %, almost twice that of a copper microsphere (44 %). The electrochemical performance showed higher catalytic properties, stability, and faradaic efficiency of silver‐decorated copper microspheres. [ABSTRACT FROM AUTHOR]

Highly efficient and selective extraction of silver ions from wastewater remains a formidable challenge in ensuring public health and protecting ecosystems. Herein, an acyl-based thiourea extractant known as N-benzoyl-N′,N′-dibutyl thiourea (BDBTU) was used for the selective extraction of silver ions from aqueous solution by a solvent extraction method. BDBTU displayed an outstanding extraction efficiency of Ag(I) with an extraction ratio of 96.7% under the optimal extraction conditions, surpassing its effectiveness for Cu(II) and Mn(II) ions. In addition, BDBTU retained high effectiveness even after undergoing eight regeneration cycles, with only a slight decrease in the extraction efficiency from 96.7% to 95.2%. Moreover, it displayed selective extraction towards Ag(I) ions under the interference of metal ions (i.e., Cu(II), Pb(II), Mn(II), Zn(II), Ni(II), Co(II) and Na(I)). The investigation into the extraction mechanism of BDBTU towards Ag(I) unveiled that BDBTU provided a high affinity for Ag(I) accompanied by the formation of Ag–O–C and Ag–S–C bonds. These results indicated that the exceptional extraction stability and selectivity of BDBTU offer promising prospects for diverse applications, highlighting its potential in silver-containing wastewater treatment fields. [ABSTRACT FROM AUTHOR]

Strategies based on nanomaterials for sterilization address the problem of antibiotic resistance faced by conventional antimicrobials, with the contribution of photocatalytic compounds being particularly prominent. Herein, to integrate multiple bactericidal techniques into a system for generating synergistic antibacterial effects, a novel photo-triggered AuAg@g-C3N4 composite nanoplatform was constructed by anchoring AuAg on the surface of a g-C3N4 layer. As the composite nanoplatform had a lower bandgap and superior visible light utilization efficiency, it could facilitate free electron transfer better and exhibit superior photocatalytic activity under light conditions. Moreover, the AuAg@g-C3N4 composite nanoplatform integrated the bactericidal modes of silver ion toxicity, physical disruption of bacterial cell membranes by the multilayer structure, and excellent photocatalytic activity, exhibiting extremely superior bactericidal effects against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus subtilis, with a bactericidal efficiency of up to 100%. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive exploration of the electrochemical behavior of layer‐by‐layer assemblies comprising silver nanoparticles (AgNPs), poly‐l‐lysine (PLL), and bovine serum albumin (BSA) on gold surfaces. AgNPs were synthesized using the reduction of silver ions with the synergy of ascorbic acid and citrate in the presence of sodium chloride. The obtained silver nanoparticles were characterized using transmission electron microscopy, dynamic light scattering and UV‐Vis spectroscopy. A typical preparation produced AgNPs with a plasmon peak at 402 nm, a diameter of 27.5 nm and zeta potential of −37 mV. Employing a drop‐coating approach, we successfully achieved stable multilayers of AgNPs, PLL, and BSA. Cyclic voltammetry revealed well‐defined, bell‐shaped oxidation and reduction peaks of AgNPs within the multilayers, demonstrating complete conversion to AgCl and back to Ag. Notably, the stripping of AgNPs on a monolayer of PLL prepared at pH 4.00 resulted in the highest current intensity, contrasting with lower intensities observed for PLL monolayers prepared at pH 7.01 and pH 9.01. Despite the absence of a splitting reduction peak in the presence of biopolymer materials, a noteworthy observation emerged: the peak splitting exclusively occurred when PLL/AgNP layers, terminated with PLL, were exposed to BSA in the solution. [ABSTRACT FROM AUTHOR]

Due to their exceptional physicochemical features, green synthesized silver nanoparticles (AgNPs) have been of considerable interest in cancer treatment. In the present study, for the first time, we aimed to green synthesize AgNPs from Euphorbia retusa and explore their anticancer potential on human breast cancer (MCF‐7) cells. First, the green synthesized AgNPs (EU‐AgNPs) were well characterized by UV–visible spectroscopy, Fourier transmission infrared (FTIR) spectrum, XRD, scanning and transmission electron microscopy (SEM and TEM), and EDX techniques. The characterization data exhibited that EU‐AgNPs were spherical in shape and crystalline in nature with an average size of 17.8 nm. FTIR results established the presence of active metabolites in EU‐AgNPs. Second, the anticancer effect of EU‐AgNPs was evaluated against MCF‐7 cells by MTT and neutral red uptake (NRU) assays. Moreover, morphological changes, ROS production, MMP, and apoptotic marker genes were also studied upon exposure to cytotoxic doses of EU‐AgNPs. Our results showed that EU‐AgNPs induce cytotoxicity in a concentration‐dependent manner, with an IC50 value of 40 μg/mL. Morphological changes in MCF‐7 cells exposed to EU‐AgNPs also confirm their cytotoxic effects. Increased ROS and decreased MMP levels revealed that EU‐AgNPs induced oxidative stress and mitochondrial membrane dysfunction. Moreover, ROS–mediated apoptosis was confirmed by elevated levels of proapoptotic marker genes (p53, Bax, caspase‐3, and caspase‐9) and reduced levels of an antiapoptotic gene (Bcl‐2). Altogether, these findings suggested that EU‐AgNPs could induce potential anticancer effects through ROS–mediated apoptosis in MCF‐7 cells. Significance Statement: This study reports the green synthesis of silver nanoparticles (EU‐AgNPs) via a single‐step reduction of silver ions using the Euphorbia retusa plant. The green synthesized EU‐AgNPs were well characterized by various analytical techniques and possess cytotoxic potential against human breast cancer (MCF‐7) cells. This study showed that EU‐AgNPs can induce apoptotic cell death via reactive oxygen species–mediated mitochondrial pathway in MCF‐7 cells. Therefore, EU‐AgNPs may play an important role in the development of new therapeutic agents for the treatment of cancer. [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]

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]

Currently, there are quite a few data on the ways silver nanoparticles get into the aquatic environment, on their subsequent dissolution in water, and on the release of toxic Ag+ ions. Differences in the experimental conditions hinder the determination of the basic regularities of this process. In this study, the stages of oxidative dissolution of AgNPs were studied, starting from the formation of silver hydrosol in deaerated solution, the reaction of silver with oxygen and with drinking and natural waters, the analysis of intermediate species of the oxidized colloidal particles, and the subsequent particle aggregation and precipitation, by optical spectroscopy, DLS, TEM, STEM, and EDX. In the presence of oxygen, silver nanoparticles undergo oxidative dissolution, which gives Ag+ ions and results in the subsequent aggregation of nanoparticles. The carbonate hydrosol loses stability when mixed with waters of various origin. This is due to the destruction of the electric double layer, which is caused by an increase in the solution's ionic strength and the neutralization of the charge of the metal core. The environmental hazard of the silver nanoparticle hydrosol would noticeably change and/or decrease when the nanoparticles get into natural waters because of their fast precipitation and because the major part of released Ag+ ions form poorly soluble salts with ions present in water. [ABSTRACT FROM AUTHOR]

This study investigates the antibacterial N-heterocyclic carbene (NHC)–silver complexes using the SwissADME platform, a web-based tool developed by the Swiss Institute of Bioinformatics (SIB). NHCs, particularly their silver complexes, have gained significant interest in medicinal chemistry for their potential as antibacterial and anticancer agents. The effectiveness of these complexes is closely linked to their structure, including factors like lipophilicity, which enhance their ability to penetrate bacterial cells and sustain the release of active silver ions. SwissADME provides computational estimates of pharmacokinetic properties, including absorption, distribution, metabolism, and excretion (ADME) characteristics, as well as drug-likeness and toxicity assessments. By evaluating parameters like molecular weight, topological polar surface area, lipophilicity (LogP), and water solubility, SwissADME offers insights into the drug-like potential of compounds. This study is inspired by a comprehensive review of antibacterial NHC–silver complexes published from 2006 to 2023, which identified superior structures with notable biological activity. The primary aim is to determine whether these active complexes exhibit distinct SwissADME parameters compared to others, providing a deeper understanding of the factors that influence their biological efficacy and aiding in the identification of promising drug candidates. Finally, experimental stabilities of exemplary complexes were confronted with absolute LUMO values derived from DFT calculations. [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 widespread use of silver raises concerns about environmental and health risks, necessitating highly sensitive detection methods for trace silver ions (Ag+). Surface plasmon resonance (SPR) sensors offer benefits like label-free detection and rapid response, but their sensitivity for Ag+ detection is limited due to weak ion adsorption. Here, we developed an SPR sensor with MoS42−-intercalated NiAl-layered double hydroxide (LDH) as the adsorption layer of Ag+ to enhance detection sensitivity. Our sensor achieves a sensitivity of 254.75 nm/μg/L and detects Ag+ at a low concentration of 2.8 pM, outperforming various existing sensors. It also shows excellent repeatability, long-term stability, and selectivity, proving effective in real-world environmental samples. This work advances high-performance SPR sensors for heavy metal ion detection. [ABSTRACT FROM AUTHOR]

This study explores the potential of zinc and silver nanocomposites, synthesized with β-lactoglobulin, a whey protein, in promoting wound healing, using the C57BL/6J mouse model. Our research is distinct in its dual focus: assessing the antimicrobial efficacy of these nanocomposites and their impact on wound healing processes. The antimicrobial properties were investigated through minimum inhibitory concentration (MIC) assessments and colony-forming unit (CFU) tests, providing insights into their effectiveness against wound-associated microorganisms. Notably, the formulation's effective antibacterial concentration did not exhibit toxicity to mouse fibroblasts. A key aspect of our methodology involved the use of a stereoscopic microscope for detailed monitoring of the wound closure process. Additionally, the distribution and potential systemic effects of the zinc and silver ions were analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). This analysis was crucial in evaluating metal ion absorption through the wound site and estimating any toxic effects on the body. Our findings are particularly significant in the field of regenerative medicine. Transmission electron microscopy (TEM) revealed that the tested nanocomposites notably enhanced collagen deposition, a vital component in the wound healing process. Furthermore, a reduction in glycogen levels in hepatocytes was observed following treatment with these metal-protein dressings. This novel finding warrants further investigation. Overall, our findings highlight the diverse roles of zinc and silver nanocomposites in wound healing. This study not only contributes to our understanding of metal-protein complexes in tissue regeneration but also opens new avenues for research into the delivery mechanisms of such treatments for hard-to-heal wounds. [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 purpose of this study was to evaluate the efficacy of silver nanoparticles (AgNPs) prepared with aloe vera leaf extract and several antibiotics against antibiotic-resistant Shigella and Salmonella bacteria. These bacteria were obtained from Kirkuk General Hospital and re- diagnosed based on reliable diagnostic sources. According to the study, aloe vera leaf extract reduces silver ions while changing the color of the solution to reddish brown. The silver nanoparticles produced by the aloe vera plant were detected using a UV-visible spectrophotometer and found to fall at wavelengths (430( nm The results of (111), (200), and (220) indicate that silver particles and antibiotic tablets extracted from aloe vera leaves (amoxicillin, chloramphenicol, erythromycin, and ciprofloxacin) have synergistic effects against drug-resistant bacteria such as shigella and salmonella. As a result, their antimicrobial efficacy was enhanced. [ABSTRACT FROM AUTHOR]

A fluorescence probe was designed using a nitrogen-contained mesoporous hyper-cross-linked polymer precursor (NH2-HCP) in order to selectively detect silver (Ag+) ions. NH2-HCP exhibits fluorescence intensity, but upon the addition of Ag+, a significant enhancement in fluorescence signal is observed. The relationship between fluorescence intensity enhancement and Ag+ concentration shows a linear and monotonic trend. The probe's response to various other cations such as Al3+, Fe3+, Cd2+, Ni2+, Cu2+, Fe2+, Hg2+, Mg2+, Zn2+, Pb2+, Mn2+, Co2+, Ca2+, Na+, and K+, as well as halogen anions like F−, Cl−, Br−, and I− was also investigated. Under optimal conditions, the probe demonstrated a linear range of 0.1-3 μM and a detection limit of 0.01 μM. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of silver nanoparticles (AgNP's) by reducing silver ions from a solution of silver nitrate with an aqueous extract from Azadirachta indica. Using silver ions as the catalyst, nanoparticles were formed in 8 min without the use of toxic chemicals. As evidenced by UV-vis spectroscopy, a broad surface plasmon resonance spectrum at 225 nm was detected, which indicates the colloidal solution of silver nanoparticles is stable and produces silver nanoparticles. As revealed by the fourier transform-infrared spectrometer (FTIR) analysis, the flower extract contained a variety of biomolecules that acted as capping and reducing agents for the synthesis of AgNPs. As determined by X-ray diffraction (XRD), silver nanoparticles displayed a crystalline structure and ranged in size from 18 to 39 nm. In addition to these findings, transmission electron microscopy (TEM) images showed that the silver nanoparticles were spherical and rod-shaped, as confirmed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). A variety of pathogenic bacteria, such as Klebsiella pneumoniae, Escherichia coli, Bacillus subtilis and Staphylococcus aureus, were tested against AgNP's antibacterial properties. A significant inhibition zone was observed for Escherichia coli when AgNPs were applied at different concentrations. Silver nanoparticles were shown to have antidiabetic effects through a diphtheria assay with inhibition rates ranging from 31.09% to 83.33% for concentrations of 50–250 μ g/mL. As researchers seek natural sources of compounds with potential health benefits, silver nanoparticles were also investigated for their antioxidant properties. Silver nanoparticles (AgNPs) were synthesized, using an aqueous extract from Azadirachta indica, as a reducing agent. UV-vis spectroscopy, shown a broad surface plasmon resonance spectrum at 225 nm, where SEM and HRTEM analyses revealed that the AgNPs were spherical and rod-shaped with sizes ranging from 18 to 39 nm. The AgNPs demonstrated significant antimicrobial properties against various pathogens and exhibited potent antioxidant activity, suggesting their potential for therapeutic applications. [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]

A novel class of hydrogels, rich in a variety of functional groups capable of interacting/complexing with metal ions was successfully synthesized. This was achieved by using acryloyl derivatives of natural α-amino acids, specifically ornithine and cystine. The δ-amino group of ornithine was modified with an acryloyl group to facilitate its attachment to the polymer chain. Additionally, N,N'-bisacryloylcystine, derived from cystine, was employed as the cross-linker. The hydrogel was obtained through a process of free radical polymerization. This hydrogel, composed only from derivatives of natural amino acids, has proven to be a competitive sorbent and has been effectively used to remove heavy metal pollutants, mainly lead, copper, and silver ions, from aqueous media. The maximum sorption capacities were ca. 155 mg·g−1, 90 mg·g−1, and 215 mg·g−1, respectively for Pb(II), Cu(II), and Ag(I). The material was characterized by effective regeneration, maintaining the sorption capacity at around 80%, 85%, and 90% for Cu(II), Ag(I), and Pb(II), respectively, even after five cycles. The properties of sorption materials, such as sorption kinetics and the effect of pH on sorption, as well as the influence of the concentration of the examined metal ions on the swelling ratio and morphology of the gel, were investigated. The EDS technique was employed to investigate the composition and element distribution in the dry gel samples. Additionally, IR spectroscopy was used to identify the functional groups responsible for binding the studied metal ions, providing insights into their specific interactions with the hydrogel. [ABSTRACT FROM AUTHOR]

Silver is widely used, but the pollution caused by silver ions is also a problem that cannot be ignored. Detection of heavy metal ions based on bulky and costly analytical instruments had been developed very maturely in the laboratory. At present, the main detection methods of silver ion concentration include inductively coupled plasma mass spectrometry, atomic absorption spectrometry and inductively coupled plasma/atomic emission spectrometry. However, these testing methods have many problems to be solved, such as the high of instruments, high operating cost, numerous operational requirements, long testing time and complex processing technology. Nowadays, with the rapid and powerful development of smartphone technology, the new analytical methods based on smartphones equipped with a camera are being carried in the certain applied ideas. Here, the paper introduces a hand-held detection platform smartphone-based that allows the quantification of silver(I) ions with the detection limit of 0.659 mM. The Colour Grab software of android smartphone was applied to obtain R, G, B values of the photo of Rhodamine B solution remaining fluorescence, and then calculated the corresponding grey values by grey formula. The detection platform based on smart phones has the characteristics of cost-effective design and simple operation, as well as high sensitivity and selectivity. Therefore, compared with other detection methods, this method can be widely and conveniently applied to the detection of silver ions in the environment. [ABSTRACT FROM AUTHOR]

An immunochromatographic test system based on the indirect competitive format has been developed for the rapid control of cyanotoxin microcystin-LR (MC-LR) in drinking water. To increase the assay sensitivity, a hydroquinone-based reduction of silver ions on the surface of gold nanoparticles as part of the immune complexes formed on the immunochromatographic membrane has been carried out. This stage allows for the enhancement of the colouration in test strip zones. The developed test system is characterised by an instrumental limit of detection of 0.05 ng/mL, a cut-off of 0.5 ng/mL, and a working range of the detectable concentrations of 0.08–0.42 ng/mL. The assay duration was 17 min. The applicability of the test system for MC-LR detection in drinking water is demonstrated. The assay recoveries vary from 90% to 120%. [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]

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]

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]

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]

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]

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]

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]

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]

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]