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Ionizing irradiation was performed on barium–germanium–gallium (BGG) glasses using a 2.5 MeV electron beam. Through electron spin resonance spectroscopy, paramagnetic point defects, such as germanium- and gallium-related electron and hole trap centers, have been identified. The presence of silver in the BGG glass appears to hinder the stability of these defects at lower energy doses (104 Gy), with silver becoming the main trapping center. At higher energy doses (106 Gy), the glass undergoes structural modifications, hindering the trapping process of silver ions. Additionally, we evidence the importance of alkaline elements such as potassium and sodium on silver ions trapped centers' formation. [ABSTRACT FROM AUTHOR]

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 study, we report the synthesis and comprehensive characterization of a new calcium-based metal–organic framework, {[Ca(Cei)(H2O)2]·3H2O}n (Ca-MOF), using bis(2-carboxyethyl)isocyanurate (H2Cei) as the organic linker. The Ca-MOF and its silver-doped derivative (Ag@Ca-MOF) were characterized in detail using single-crystal X-ray diffraction (SCXRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDAX), powder X-ray diffraction (PXRD), Raman spectroscopy, Brunauer–Emmett–Teller (BET) surface area analysis, and X-ray photoelectron spectroscopy (XPS), which confirmed the successful incorporation of silver ions. Photocatalytic studies revealed that Ag@Ca-MOF-2 exhibited superior degradation efficiency for Bisphenol A (BPA) under visible light (92.81%) compared to the undoped Ca-MOF (37.52%). Antimicrobial assays demonstrated enhanced activity of Ag@Ca-MOF-2, achieving minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of ≤128 mg L−1 against Staphylococcus aureus and a MIC of ≤128 mg L−1 and MBC of ≤256 mg L−1 against Escherichia coli, surpassing the Ca-MOF, which showed MIC and MBC values of ≤256 mg L−1 and ≤512 mg L−1, respectively, for both bacterial strains. Additionally, Ag@Ca-MOF-2 displayed an enhanced antioxidant capacity in the DPPH radical scavenging assay relative to the parent MOF. Furthermore, Ag@Ca-MOF-2 demonstrated a detection limit of 1.164 ppm for BPA in aqueous media, underscoring its potential as a multifunctional material with promising applications in environmental remediation and biomedical contaminant detection. [ABSTRACT FROM AUTHOR]

As a naturally occurring reducing and oxidizing agent, hydrogen peroxide (H2O2) has a role in several biotic and abiotic processes. Hence, the onsite, precise, and rapid determination of H2O2 is crucial. Herein, we propose a method for colorimetric detection of H2O2 on the basis of hindered formation of gold/silver core/shell nanoparticles. We used ascorbic acid (AA) as the electron donor to reduce silver ions (Ag+) to be shelled around gold nanoparticles and iron(III) edta as an accelerator reactant. Upon reduction of Ag+, owing to the formation of core/shell nanoparticles, the color of the system changes from pink to yellow/orange in the spherical nanoparticles and from pink to purple/blue/green/yellow/orange in the nanorods. The nanorods distinguished color in a rainbow manner for higher concentrations of H2O2, and spherical nanoparticles were critical in the sensitive detection of lower concentrations of H2O2. H2O2 scavenges AA electrons and therefore inhibits core/shell formation and, consequently, restrains the system's spectral shift and color change. This characteristic was exploited to measure different concentrations of H2O2. Under well-optimized conditions, various concentrations of H2O2 ranging from 1.0 to 50 µΜ have shown an acceptable linear relationship with different colors and, with a limit of detection (LOD) of 230 nM. Furthermore, various real samples were examined to confirm the practicality of our developed probe. [ABSTRACT FROM AUTHOR]

Silver chloride nanoparticles and microplastics are polluting in surface waters, yet their interactions, associated toxicity and environmental risks are poorly known. Here we hypothesized that polystyrene microplastics could enhance the phototransformation of silver chloride nanoparticles and modify their toxicity. We conducted phototransformation of silver chloride nanoparticles with polystyrene microplastics under light irradiation. The photo-dissolution of silver chloride nanoparticles and photo-reduction of silver ions were determined in both double-distilled-water and environmental waters. We found that polystyrene microplastics highly enhanced the phototransformation of silver chloride nanoparticles by hydroxyl radicals, singlet oxygen, and triplet state microplastics, leading to the release of silver ions and chloride ions. Subsequently, the silver ions were reduced to silver nanoparticles by superoxide radicals. Consequently, the silver species transformation increased the toxicity of silver chloride nanoparticles even at environmental concentration, as evidenced by survival rate of zebrafish larvae reduced from 100% to 23.3%. This is the first study to show that polystyrene microplastics can enhance the phototransformation of silver chloride nanoparticles to silver nanoparticles, thereby increasing the environmental risks of silver chloride nanoparticles in environmental waters. [ABSTRACT FROM AUTHOR]

Most of the existing SERS systems failed to achieve satisfactory results in early diagnosis of Alzheimer's disease owing to a lack of effective signal transduction. Herein, we developed a dual signal amplification strategy for SERS detection of amyloid-β oligomers based on proximity hybridization-triggered catalyzed hairpin assembly (CHA) and hybridization chain reaction (HCR). In the presence of the target protein and two DNA-labeled antibodies, a proximate complex formed in a homogeneous solution. Each of the AβO-DNA complexes served as a catalyst to trigger and accelerate numerous hybridization processes between MB1 and MB2. Subsequently, the single-strand fragment on the electrode surface initiated HCR, resulting in the hybridization reaction to form double-strand DNA concatemers on the substrate surface. The surface became negatively charged and allowed the absorption of silver ions on the DNA skeleton. After chemical reduction by hydroquinone, the formed silver nanoparticles could be further grown with a silver enhancement step to amplify the detectable SERS signal by absorbing rhodamine 6G as a SERS reporter on the silver nanoparticle surface. This biosensing platform had potential applications in molecular diagnostics of AD serum samples. [ABSTRACT FROM AUTHOR]

Aiming toward a novel, noninvasive technique, with a real-time potential application in the monitoring of the complexation of steroidal neuromuscular blocker drugs Vecuronium (Vec) and Rocuronium (Roc) with sugammadex (SDX, medication for the reversal of neuromuscular blockade induced by Vec or Roc in general anesthesia), we developed proof-of-principle methodology based on surface-enhanced Raman spectroscopy (SERS). Silver nanoparticles prepared by the reduction of silver ions with hydroxylamine hydrochloride were used as SERS-active substrates, additionally aggregated with calcium nitrate as needed. The Vec and Roc SERS spectra were obtained within the biorelevant 5 × 10−7–1 × 10−4 M range, as well as the SERS of SDX, though the latter was observed only in the presence of the aggregating agent. SDX/drug complexes at a 1/1 molar ratio revealed significant spectral changes in the vibrational bands of the SDX glucose rings and the drug steroid rings, implying that the insertion of Vec and Roc molecules into the SDX cavity was not only driven by attractive electrostatic interactions between the positively charged cyclic unit of the drug and the negative carboxylate groups of cyclodextrin but also supported by hydrophobic interactions between the host cyclodextrin and the guest drug molecule. The observed changes in SERS signals are applicable in biorelevant conditions and support further studies of SDX/drug complexes in vivo. [ABSTRACT FROM AUTHOR]

The emergence of multidrug-resistant (MDR) bacteria represented by MRSA (Methicillin-resistant Staphylococcus aureus) poses a great challenge to current anti-infection treatment. It is critical to develop efficient MRSA anti-bacteria drugs and explore simple therapeutic strategies with low MDR risk. Herein, we synthesized high-valent (AgII/AgIII) water-soluble porphyrins (cationic AgTMPyP and anionic AgTMPPS) and investigated their direct bactericidal property for MRSA without photoactivation in vitro and in vivo. The cationic porphyrin AgTMPyP exhibits well oxidase-like activity and has 100 % sterilizing rate at 8 μmol/L concentration. Besides, AgTMPyP can effectively destroy biofilms in vitro , mediate the polarization of macrophages from M1 to M2, and promote wound healing in vivo. Combined with DFT calculation, the related antibacterial mechanism is further discussed. High-valent silverporphyrins can maintain stable in water for at least 200 days. The moment they encounter MRSA, high-valent silver ions from AgTMPyP can be immediately released from the porphyrin ring and attack the MRSA with efficient sterilization. Together with the hemolysis, blood routine and blood biochemistry tests, it is proved that AgTMPyP can have great prospects in the direct treatment of bacterial infections in skin diseases in the future. The emergence of multidrug-resistant (MDR) bacteria represented by MRSA poses a great challenge to current anti-infection treatment. It has become critical to develop efficient MRSA anti-bacteria drugs and explore simple therapeutic strategies with low MDR risk. We synthesized high-valent (AgII/AgIII) water-soluble silver porphyrins (AgTMPyP and AgTMPPS), which can be stable for long periods in aqueous solutions. AgTMPyP can directly and efficiently kill bacteria and destroy biofilms without photoactivation in vitro and in vivo. Combined with DFT calculation, the related antibacterial mechanism is further discussed. AgTMPyP is a superior antimicrobial agent with good biocompatibility and it can have great prospects in the direct treatment of bacterial infections and wound healing in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

The chemosensors act as powerful tool in the detection of metal ions due to their simplicity, high sensitivity, low cost, low detection limit, rapid photophysical response, and application to the environmental and medical fields. This review article presents an overview for the chemosensing of Ag+ ions based on Calix, MOF, Nanoparticle, COF, Calix, Electrochemical chemosensor published from 2018 to 2023. Here, we have reviewed the sensing of Ag+ ions and summarised the binding response, mechanism, LOD, colorimetric response, adsorption capacity, technique used. The purpose of this review article to provide a detailed summary of the performance of different host chemosensors that are helpful for providing future direction to researchers on Ag+ ion detection and provides path to design effective chemsosensor (simple to synthesize, cost effective, high sensitivity, with more practical application). While studying the related article literature, we came across some challenges and that has been discussed lastly and provided solutions for them. [ABSTRACT FROM AUTHOR]

In the geological disposal of nuclear waste, the simultaneous reduction of diffusion rate of cationic and anionic radioactive species is essential. Natural calcium-bentonite only reduces the diffusion rate of cations, not anions. In this study, the half of calcium ions is bentonite was exchanged to silver ions to reduce diffusion rates of both of radioactive cation (137Cs+) and anions (36Cl−, 131I−) at the same time. This is due to the precipitation of silver halides in the interlayer space. The diffusion rate of both anionic and cationic radioactive species are small in compacted the silver-calcium bentonite. [ABSTRACT FROM AUTHOR]

Silver drugs have played a vital role in human healthcare for the treatment of infections for many centuries. Currently, due to antibiotic resistance, a potential scenario or the application of silver complexes may arise as substitutes for conventional antibiotics. In this perspective, N-heterocyclic carbene (NHC) ligands have been selected as carrier molecules for silver ions. In this study, we selected two mono NHC-silver halide complexes: bromo[1,3-diethyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]silver(I) (Ag4MC) and chloro[2-pyridin- N-(2-ethylacetylamido)-2-yl-2H-imidazol-2-ylidene]silver(I) (Ag5MC), and two cationic bis NHC silver complexes: bis[1,3-diethyl-4,5-bis(4-methoxyphenyl)imidazol-2-ylidene]silver(I) (Ag4BC) and bis[2-pyridin-N-(2-ethylacetylamido)-2-yl-2H-imidazol-2-ylidene]silver(I) (Ag5BC). The inhibitory properties of the four complexes were evaluated for their antimicrobial potential against a set of Gram (+) and Gram (−) bacterial strains and the fungus C. albicans. In addition, further investigations were made using fluorescence and scanning electron microscopy (SEM) in order to gain more insights into the mechanism of action. Some preliminary information on the Ag target was obtained by analyzing the cytosol of E. coli treated with Ag5MC by size-exclusion chromatography (SEC) coupled with inductively coupled plasma mass spectrometry (ICP-MS). [ABSTRACT FROM AUTHOR]

A new selective and highly sensitive chemosensor based on the Schiff base 1-benzylidenethiosemicarbazide (KH1) was synthesized and applied for the Ag+ sensor in 4:1 dimethyl sulfoxide-water. Upon addition of Ag+, the fluorescence intensity of KH1was increased at 350 nm. The 1:1 stoichiometry of KH1 with Ag+ was confirmed by a spectrofluorimetric titration and a Job's plot measurement. Parameters affecting the sensitivity such as pH, reaction time, ionic strength, and Schiff base concentration were optimized. Under the optimum conditions, KH1 gave a wide range of linearity from 1 to 110 µM and the limit of detection and relative standard deviation were 0.2 µM and 2.2%, respectively. In addition, the KH1 sensor was used to determine Ag+ in water samples with good precision and accuracy. [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]

Various pulp-covering materials offer advantages in regenerative root canal treatment, but each has limitations, highlighting the need for more effective antibacterial strategies for pulp repair and regeneration. Mesoporous bioactive glasses (MBG) show significant biological activity, making them valuable in tissue/dental repair. Silver-incorporated MBG exhibits promising antibacterial effects against various bacteria; copper ions are crucial in regulating angiogenesis signals. Co-loading copper and silver in bioactive glasses has been explored to address clinical challenges. This study modified the preparation of silver-copper bimetallic mesoporous bioactive glass, analyzing their textural properties and antibacterial activity against Enterococcus faecalis. The silver-copper co-loaded bioactive glass (designated as AgCu/80S) was synthesized using a sol–gel technique with modifications. Textural analyses were carried out via X-ray diffraction, UV–Vis spectroscopy, Brunauer–Emmett–Teller analysis, and transmission electron microscope. The ion-releasing activity determined using inductively coupled plasma-mass spectrometry, and the antibacterial activity against E. faecalis was assessed through disk diffusion and kinetic bacterial growth curve. The modification led to weaker crystallization of calcium silicate, altering ion-releasing and antibacterial activities. Ag3Cu2/80S exhibited the highest released silver ion concentration at 112.6 ppm, with an inhibition zone of 9.09 ± 0.09 mm in disk diffusion assays. However, the inhibition zone of Ag2Cu3/80S was 9.92 ± 0.04 mm, implying that the antibacterial activity may not only be influenced by silver ions. The AgCu/80S showed a potential antibacterial activity against E. faecalis , whereas further research on AgCu/80S glasses is necessary to optimize ion release conditions, assess bioactivities, and explore potential dental applications. [ABSTRACT FROM AUTHOR]

Water-soluble purple fluorescent carbon nanodots (P-CDs) were synthesised using 2-phenylphenol, and red fluorescent carbon dots (R-CDs) were prepared from o-phenylenediamine and phosphoric acid. Based on the fluorescence quenching effect of Ag+ on carbon quantum dots, and additionally introducing a red light-emitting quantum dot with excellent performance and high quantum yield, a dual emission ratiometric fluorescent nanosensor (P-CDs/R-CDs) was established. The semi-quantitative detection of silver ions can be realised. Under the excitation light of 254 nm and 365 nm, the fluorescence spectrum shows double emission fluorescence peaks at 343 nm and 626 nm, which originate from the fluorescence emission of the synthesised C-dots and the additionally introduced C-dots, respectively. The relationship between the ratio of the intensity of the two emission peaks F343/F626 and the concentration of silver ions realises the analysis and detection of silver ions. The linear detection range of this method was 0.096–10 μM, and the detection limit (LOD, S/N = 3) was 32 nM. In addition, the method can also perform naked-eye visual detection according to the fluorescence colour change of the probe under ultraviolet light, and realise the rapid monitoring of Ag+ on site. The P-CDs/R-CDs ratiometric fluorescence sensor provides a new method for the detection of Ag+ and promotes the development of heavy metal ion sensing. [ABSTRACT FROM AUTHOR]

Water-soluble purple fluorescent carbon nanodots (P-CDs) were synthesised using 2-phenylphenol, and red fluorescent carbon dots (R-CDs) were prepared from o-phenylenediamine and phosphoric acid. Based on the fluorescence quenching effect of Ag+ on carbon quantum dots, and additionally introducing a red light-emitting quantum dot with excellent performance and high quantum yield, a dual emission ratiometric fluorescent nanosensor (P-CDs/R-CDs) was established. The semi-quantitative detection of silver ions can be realised. Under the excitation light of 254 nm and 365 nm, the fluorescence spectrum shows double emission fluorescence peaks at 343 nm and 626 nm, which originate from the fluorescence emission of the synthesised C-dots and the additionally introduced C-dots, respectively. The relationship between the ratio of the intensity of the two emission peaks F343/F626 and the concentration of silver ions realises the analysis and detection of silver ions. The linear detection range of this method was 0.096–10 μM, and the detection limit (LOD, S/N = 3) was 32 nM. In addition, the method can also perform naked-eye visual detection according to the fluorescence colour change of the probe under ultraviolet light, and realise the rapid monitoring of Ag+ on site. The P-CDs/R-CDs ratiometric fluorescence sensor provides a new method for the detection of Ag+ and promotes the development of heavy metal ion sensing. [ABSTRACT FROM AUTHOR]

To enhance the current clinical understanding and improve the diagnosis and treatment of Actinotignum schaalii infections, we have presented here a report of the case of recurrent infections at a periumbilical scar, induced by Actinotignum schaalii and complicated by abscess formation in a 50-year-old woman with persistent festering at the site of a periumbilical scar after laparoscopy 9 years ago, with subsequent ruptures over the past 2 years. Physical examination revealed a radial fold scar with localized redness and slight swelling of the skin below the navel. Although no significant increase in the local skin temperature was noted, tenderness was present. A rupture at the site was also observed, and gentle compression produced a small amount of odorless and yellowish viscous pus. Anerobic culturing of the pus for 3 days revealed gray-white, non-hemolytic, spore-free, gram-positive, slightly curved rod-shaped bacteria. These bacteria were identified as A. schaalii using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The patient was subsequently treated with a 1-month course of oral amoxicillin, combined with debridement and drainage. Her condition improved with regular dressing changes. However, during follow-up 6-month later, the patient presented with a recurrence of the local infection at the scar site, again accompanied by abscess formation and rupture. Notably, the wound size was smaller, and after a 1-week treatment with silver ion, without any systemic antibiotic administration, her condition improved. Next, triamcinolone acetonide combined with lidocaine was injected into the scar three times. No further local infections were observed at the scar site during the subsequent 12-month follow-up. [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]

Biosurfactants prevent agglomeration of nanoparticles by reducing the surface tension and offer stability over time by forming a stable layer on the surface of nanoparticles. The current study focuses on the biosynthesis of silver nanoparticles (SNP) coated with a rhamnolipid biosurfactant (BS) and its use as an additive in fabric cleaning detergent. Rhamnolipids were extracted from a Pseudomonas aeruginosa strain, Pa84, that was isolated from a halophilic environment, Sambhar Salt Lake, Rajasthan, India. The reduction of silver ions was achieved by the rhamnolipid‐coated SNP (BS‐SNP). BS, SNP, and BS‐SNP demonstrated antibacterial efficacy against a variety of microorganisms. Lipase, present in the crude biosurfactant, was immobilized on modified chitosan microbeads (Ch‐BS‐SNP) and used for washing fabrics. The conjugate was found to be effective as a laundry detergent additive. The immobilized lipase showed high relative activity ranging from 66% to 110% and performed better than free lipase or standards. Our results highlight a potential claim for a commercially viable laundry detergent additive. [ABSTRACT FROM AUTHOR]

Expanding on our previous efforts demonstrating the feasibility of extracting chemical information in steady-state systems of nanoparticles under irradiation, we demonstrate that the Cherenkov spectra can be used to observe chemical changes in real-time, in situ, and for non-equilibrium systems under irradiation. This is done by way of a dose-resolved measurement of the localized plasmon resonance absorption band associated with the formation and growth of silver nanoclusters and nanoparticles produced via radiolytic reduction of a solution of silver ion under exposure to an electron beam. Additionally, the method utilized in this study provided a significant resolution with a simplified optical system. This paves the way for a technique to determine similar changes in the material in medicinal, industrial (nuclear industry), and research applications—and indeed in any application involving ionizing radiation. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic highlighted the urgent need for improved personal protective equipment (PPE). Green-synthesised silver nanoparticles (AgNPs) using pandan (Pandanus amaryllifolius) extract offer a sustainable solution to enhance PPE effectiveness against infectious diseases. This eco-friendly approach utilises pandan's bioactive compounds to reduce silver ions into nanoparticles, providing a sustainable alternative to conventional chemical synthesis methods. The resulting AgNPs exhibit potent antimicrobial and antiviral properties, making them valuable for incorporation into PPE fabrics and coatings. Beyond antimicrobial benefits, pandan-derived AgNPs may impart natural fragrances and skin-soothing properties, enhancing user comfort. The green synthesis process reduces environmental impact and potential toxicity associated with conventional chemical methods. While challenges in scaling production, ensuring regulatory compliance, and assessing long-term health and environmental effects persist, pandan-derived AgNPs-coated PPE represents an innovative approach to infection prevention. This technology has the potential to significantly improve safety measures in healthcare and other high-risk environments while promoting sustainability. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are increasingly recognized as vital nanomaterials in biomedical applications due to their diverse pharmacological properties, including antimicrobial and anti-neoplastic effects, particularly when derived from herbal sources. This study aims to synthesize AgNPs employing a sustainable approach aligned with the principles of the sustainable development goals. The synthesized AgNPs are incorporated with doxorubicin (DOX) and encapsulated within polylactide nanoparticles to enhance their anticancer potency. AgNPs are prepared via the reduction of silver ions using rutin as a reducing agent, with the reaction progress monitored via ultraviolet-visible spectroscopy (UV-vis). Subsequently, the AgNPs are encapsulated into poly(D, L-lactic acid) (PDLLA) nanoparticles alongside doxorubicin. The developed nanoparticles have shown a diameter size of 233 nm with a zeta potential of -21.47 mV. Moreover, the in vitro release profile of the DOX showed a sustained release kinetics over 30 h. Evaluation of the AgNP-DOX-loaded PDLLA nanoparticles reveals enhanced anticancer activity against HeLa and HepG2 cancer cells, highlighting the synergistic efficacy of the combined therapy. These findings underscore the potential of AgNPs-based formulations as promising candidates for advanced cancer therapeutics. [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]

The present study synthesized silver nanoparticles supported on a thermosensitive polymer with a core–shell structure, formed by a polystyrene (PS) core and a poly(N-isopropylacrylamide) (PNIPAM)/Poly(N, N-methylenebisacrylamide) (MBA) shell. The PS core was synthesized via semicontinuous heterophase polymerization at a flow of 0.073 g/min, enabling polystyrene nanoparticles with an average size (Dz) of 35.2 nm to be obtained. In the next stage, the conditions required for polymerization synthesis were established in seeded microemulsion using PS nanoparticles as seed and semicontinuously adding the thermosensitive shell monomer (PNIPAM/MBA) under monomer-flooded conditions to favor shell formation. The non-homopolymerization of PNIPAM/MBA was demonstrated by obtaining nanoparticles with a core–shell structure, with average particle sizes of 41 nm and extremely low and narrow polydispersity index (PDI) values (1.1). The thermosensitive behavior was analyzed by QLS, revealing an average shrinkage of 4.03 nm and a percentage of shrinkage of 23.7%. Finally, silver nanoparticles were synthesized on the core–shell heat-sensitive nanoparticles in a colloidal solution containing the latices, while silver nanoparticles were anchored onto the cross-linked heat-sensitive network via the formation of complexes between the Ag+ ions and the nitrogen contained in the PNIPAM/MBA network, favoring anchorage around the network and maintaining a size of 5 nm. [ABSTRACT FROM AUTHOR]

Skin plays an important role in several body functions. Once the skin integrity is lost because of injury, finding an effective way to facilitate the wound healing process is extremely essential. In this study, an appropriate composite is designed for wound dressing based on gelatin scaffold containing Ag nanoparticles decorated polydopamine nanoparticles (PDA-Ag NPs), to reduce wound bacterial colonization and accelerate the healing process. The prepared nanoparticles and scaffolds were then chemically and physically characterized by FTIR, FESEM, EDX and DLS. The scaffolds' water uptake, mechanical strength and silver ion release were also measured. Biological analysis including antibacterial test and cell viability were investigated. DLS results indicated that the average diameter of synthesized PDA-Ag NPs was 383 ± 14.3 nm. By adding PDA-Ag NPs to gelatin-based scaffold, the maximum tensile strength increased from 0.388 ± 0.120 to 0.483 ± 0.112 MPa, tensile modulus increased from 0.058 ± 0.017 to 0.083 ± 0.015 MPa as well. Water uptake of gelatin-based scaffolds has also indicated about 800 to 1400% increase compared with the initial weight. The antibacterial, good biocompatibility and cell adhesion results verify the prepared scaffolds potential for wound dressing applications. [ABSTRACT FROM AUTHOR]

Silver deposits have long been considered to form due to the direct precipitation of silver minerals from aqueous fluids, in which the metal is transported as chloride and/or bisulfide complexes. Ultra-high-grade silver ores have silver contents up to tens of weight-percent in the form of silver sulfides and native silver. Ore-forming fluids of most silver deposits, however, typically contain low silver contents of parts per million silver. The challenge is to explain how fluids with such low concentrations of silver can form ultra-high-grade silver ores. Here, we present direct mineralogical evidence from natural samples showing that the high-grade silver ores form from the aggregation of silver sulfide nanoparticles through intermediate microparticles and dendrites to acanthite crystals. Native silver grows from silver sulfides via solid-state silver ion aggregation. This study traces the formation of silver sulfides from their nanoparticulate precursors, thereby providing insights into the genesis of ultra-high-grade silver ores in a variety of metallogenic settings. This study traces a pathway for the natural formation of silver sulfide and silver wire through the coalescence of silver sulfide nanoparticles and solid-state silver ions aggregation that is responsible for high-grade silver deposits [ABSTRACT FROM AUTHOR]

Diabetic wound healing presents a persistent clinical challenge, often characterized by prolonged healing times, and can be particularly difficult to achieve in a hyperglycemic environment. In this study, a multi‐functional silver‐enzyme nanogels assembly (Ag‐nGHC) is designed by focusing on the complex diabetic wound environment. Glucose oxidase (GOX), horseradish peroxidase (HRP), and catalase (CAT) are modified within polymeric nanogel layers and assembled into a large enzyme cluster with silver ions. The close attachment of three enzymes ensures fast and continuous consumption of a high level of glucose, generation of oxygen, and hydroxyl radicals (•OH) around the wound site. Meanwhile, the silver ions within the Ag‐nGHC assembly act as an effective agent to kill bacteria. This cascade enzyme system significantly improves the microenvironment of the wound site by reducing bacterium infection and alleviating hypoxia as well as hyperglycemia. Sequentially, the improved environment facilitates the later processes including anti‐inflammatory, re‐epithelialization, and angiogenesis, evidenced by enhancing polarization toward M2 macrophages and increasing CD31 signals in this study. Overall, the Ag‐nGHC materials are proven to achieve multifunctional properties toward complicated diabetic wound healing processes (attributes such as adaptability, hypoxia‐alleviated, anti‐hyperglycemic, antimicrobial, anti‐inflammatory, and angiogenic) and showed great potential for the treatment of chronic diabetic wound. [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]

A multifunctional fluorescent probe P based on a naphthalimide derivative for the detection of Ag+ and Hg2+ through a dual-signal was designed and characterized. P exhibited a large Stokes shift (107 nm), high selectivity, good sensitivity, and fast response time. By adjusting the testing medium and the order of reagent addition, multifunctional detection with P was achieved. The addition of Ag+ or Hg2+ to P solution in either ethanol or an ethanol–water mixture resulted in a significant quenching of fluorescence emission at 537 nm and caused a decrease in the absorbance at 440 nm accompanied by the appearance of a new absorption peak at around 340 nm, and there was an obvious color change from yellow to colorless. In contrast, the addition of other common metal ions and anions did not produce substantial spectral or color changes. The detection limit of probe P for Ag+ and Hg2+ was calculated to be 0.33 μM. The sensing mechanism was proposed and validated through MS and 1H NMR spectrometry methods. Additionally, P demonstrated the capability to recognize Ag+ and Hg2+ in living cells with satisfactory results. [ABSTRACT FROM AUTHOR]

Several bacterial strains have developed resistance against commercial antibiotics, and interestingly, supramolecular nanomaterials have shown considerable advantages for antibacterial applications. However, the main challenges in adopting nanotechnology for antibacterial studies are random aggregation, compromised toxicity, multi-step preparation approaches, and unclear structure-function properties. Herein, we designed the amphiphilic tripeptide that acts as a reducing and capping agent for silver metal to form silver-peptide colloidal nanohybrids with the mild assistance of UV light (254 nm) through the photochemical reduction method. The nanohybrids are characterized by different spectroscopic and microscopic techniques, and non-covalent molecular interactions between metal and peptide building blocks confirm their central role in the formation of nanohybrids. The tripeptide is biocompatible and can reduce the toxicity of silver ions (Ag+) by reducing to Ag0. These colloidal nanohybrids showed antibacterial activity against gram-negative and gram-positive bacterial strains, and the possible mechanism of killing bacterial cells could be membrane disruption. This synthetic strategy is facile and green, which helps avoid using toxic chemicals or reagents and complicated methods for colloidal nanohybrid preparation for biomedical applications. [ABSTRACT FROM AUTHOR]

The biosynthesis of silver nanoparticles (AgNPs) presents an innovative and sustainable approach in nanotechnology with promising applications in fields such as medicine, food safety, and pharmacology. In this study, AgNPs were successfully synthesized using the probiotic strain Lacticaseibacillus rhamnosus (BCRC16000), addressing challenges related to stability, biocompatibility, and scalability that are common in conventional nanoparticle production methods. The formation of AgNPs was indicated by a color change from yellow to brown, and UV–visible spectrophotometry confirmed their presence with a characteristic absorption peak at 443 nm. Furthermore, Fourier transform infrared (FTIR) spectroscopy revealed the involvement of biomolecules in reducing silver ions, which suggests their role in stabilizing the nanoparticles. In addition, field emission scanning electron microscopy (FE-SEM) showed significant morphological and structural changes. At the same time, dynamic light scattering (DLS) and zeta potential analyses provided valuable insights such as average size (199.7 nm), distribution, and stability, reporting a polydispersity index of 0.239 and a surface charge of −36.3 mV. Notably, the AgNPs demonstrated strong antibacterial activity and photocatalytic efficiency, underscoring their potential for environmental and biomedical applications. Therefore, this study highlights the effectiveness of Lacticaseibacillus rhamnosus in the biosynthesis of AgNPs, offering valuable antibacterial and photocatalytic properties with significant industrial and scientific implications. [ABSTRACT FROM AUTHOR]

The high incidence of disability and fatality rates associated with chronic diabetic wounds are difficult problems in the medical field. The steady-state and regular changes of the microenvironment in and around the wound provide good conditions for wound healing and achieve a dynamic and complex process of wound healing.The pH value and ionic environment composed of a variety of ions in wound are important factors affecting the wound microenvironment, and there are direct or indirect connections between them. Abnormalities in pH, ion concentrations, and channels in skin tissue may be one of the reasons for the high incidence and difficulty in chronic diabetic wounds healing. Currently, different wound-dressing applications have been developed based on the efficacy of ions. Here, the effect of pH in wounds, concentrations of calcium (Ca2+), sodium (Na+), potassium (K+) and the metal ions silver (Ag+), copper (Cu2+), iron (Fe2+/Fe3+), zinc (Zn2+), and magnesium (Mg2+) in skin tissue, their roles in wound healing, and the application of related dressings are reviewed. This manuscript provides new ideas and approaches for future clinical and basic research examining the treatment of chronic diabetic wounds by adjusting ion concentrations and channels. [ABSTRACT FROM AUTHOR]

Incorporating nanoparticles into polymer matrices for enhanced antimicrobial properties is particularly interesting. This study examines how the interlayer distribution of zinc oxide (ZnO) decorated with silver nanoparticles (AgNPs) within poly(methyl methacrylate) (PMMA) films impacts their antimicrobial activity. Various PMMA multilayer films were prepared, with the antimicrobial additive intentionally placed in the outer, core, bottom, or throughout all layers. Their efficacy was tested against gram‐negative (Escherichia coli) and gram‐positive (Staphylococcus aureus) bacteria. Results indicate that E. coli was the strain with the highest sensitivity to the system because it is a gram (−) bacterium, which could generate a lower resistance to AgNPs. On the other hand, S. aureus, being gram (+), presents a thicker lipid membrane, and peptidoglycan wall, which makes it difficult for AgNPs to enter. Films with uniform distribution throughout thickness exhibited the most sustained antimicrobial activity due to high antimicrobial concentration. This study demonstrated that the distribution of the AgNPs/ZnO system in different layers of a PMMA film influences its antimicrobial capacity. Finally, a mechanism for migrating silver ions released from the AgNPs/ZnO system in PMMA films is proposed, highlighting their interactions with bacterial cells and the subsequent antimicrobial effects. Highlights: Interlayer distribution influences antimicrobial activity.Outer placement leads to rapid silver ion release.Core distribution controls antimicrobial kinetics.Uniform distribution ensures sustained activity. [ABSTRACT FROM AUTHOR]

In order to explore the effect of njpo-silver on functional modification of wool fabric, based on the oxidation of laccase and the reduction of polydopamine, polydopamine coating was formed on the surface of chitosan modified wool, and silver ions adhering to the surface of the fabric were reduced to silver nanoparticles, so as to prepare multi-functional modified wool fabric. The results show that the fabric surface covered with a layer of polydopamine coating can make up for tip strength damage caused by pretreatment, and its wettability can be improved. Compared with the plump and soft feel of the uncoated fabric, the feel of the modified fabric is slightly stiff and rough. The prepared multifunctional modified wool fabric has good anti-ultraviolet and antibacterial effects. [ABSTRACT FROM AUTHOR]