The 2,7-fluorenone-linked bis(6-imidazo[1,5-a]pyridinium) salt H2-1(PF6)2 reacts with Ag2O in CH3CN to yield the [2]catenane [Ag4(1)4](PF6)4. The [2]catenane rearranges in DMF to yield two metallamacrocycles [Ag2(1)2](PF6)2. 2,7-Fluorenone-bridged bis-(imidazolium) salt H2-L(PF6)2 (L = 2a, 2b) react with Ag2O in CH3CN to yield metallamacrocycles [Ag2(L)2](PF6)2 with interplanar distances between the fluorenone rings too small for [2]catenane formation. Intra- and intermolecular p···p interactions between the fluorenone groups were observed by X-ray crystallography. The strongly kinked 2,7-fluorenone bridged bis(5-imidazo[1,5-a]pyridinium) salt H2-4(PF6)2 reacts with Ag2O to yield [Ag2(4)(CN)](PF6) while the tetranuclear assembly [Ag4(4)2(CO3)](PF6)2 was obtained in the presence of K2CO3.

UNASSIGNED: A fracture is considered a medical emergency leading to considerable complications.
UNASSIGNED: This study aimed to describe the accelerating action of Ag-NPs-FG on fracture healing in rabbits.
UNASSIGNED: Silver NPs (AgNPs) were reduced with fenugreek (FG), loaded into a starch gel base, and investigated for their morphology, size, and charge. Four equal groups were randomly formed of 40 adult male rabbits. A 3.5 mm diameter bone defect was created at the proximal metaphysis of the right tibia in each rabbit. Groups 1-4 were injected with placebo saline, AgNPs-FG, plain gel, and FG-gel at the bone defect zone, respectively. The healing was assessed for 8 weeks postoperatively based on the radiographic, bone turnover markers, and histopathological examinations.
UNASSIGNED: The AgNPs-FG was obtained as a faint reddish color, spherical in shape, with an absorbance of 423 nm, a size of 118.0 ± 1.7 nm, and a surface charge of -7.8 ± 0.518 mV. The prepared AgNPs-FG hydrogel was clear, translucent, and homogenous. The pH values were 6.55-6.5 ± 0.2, the viscosity of 4,000 and 1,875 cPs, and spreadability of 1.6 ± 0.14 and 2.0 ± 0.15 for both FG and AgNPs-FG hydrogel, respectively. The radiographic union scale was significantly (p < 0.05) improved in group 2 with a significant (p < 0.05) increase in bone turnover markers was found in comparison to other treated groups. Histopathological examination revealed the formation of mature bone on the 28th postoperative day in groups 2 and 4.
UNASSIGNED: Colloidal nano-formulation of AgNPs-FG loaded hydrogel could be a promising formulation to accelerate rabbits\' tibial bone healing process.

A highly sensitive, selective and recyclable histidine detection method based on magnetic Fe3O4@mTiO2 (M-TiO2) nanocomposites with SERRS was developed. Mesoporous M-TiO2 nanoparticles were functionalized with 4-aminothiophenol and then coupled with histidine through an azo coupling reaction in 5 min, producing the corresponding azo compound. The strong and specific SERRS response of the azo product allowed for ultrasensitive and selective detection for histidine with an M-TiO2 device loaded with Ag NPs due to the molecular resonance effect and plasmonic effect of Ag NPs under a 532 nm excitation laser. The sensitivity was further enhanced with the magnetic enrichment of M-TiO2. The limit of detection (LOD) was as low as 8.00 × 10-12 mol/L. The M-TiO2 demonstrated applicability towards histidine determination in human urine without any sample pretreatment. Additionally, the M-TiO2 device can be recycled for 3 cycles with the photodegradation of the azo product under UV irradiation due to TiO2-assisted and plasmon-enhanced photocatalysis. In summary, a multifunctional and recyclable M-TiO2 device was synthesized based on azo coupling and SERRS spectroscopy for ultra-sensitive and specific histidine sensing. In addition, the proposed system demonstrated the potential for the multiplex determination of toxic compounds in the fields of food safety, industrial production and environmental protection, which benefit from the fingerprint property and universality of SERRS.

Solution-processed graphene is beneficial for large-scale, low-cost production. However, its small lateral size, variable layer thickness, and uncontrollable oxidation level still restrict its widespread electronic application. In this study, a newly developed electrochemical exfoliation process was introduced, and a graphene-patched film electrode was fabricated by interfacial self-assembly. We were able to minimize the deterioration of graphene colloids during exfoliation by voltage and electrolyte modulation, but the patched structure of the graphene electrode still showed low conductivity with numerous inter-sheet junctions. Therefore, we determined the optimal conditions for the growth of fully networked silver structures on the multi-stacked graphene film by direct current electro-deposition, and these silver-graphene composite films showed significantly lowered graphene-colloid-patched film surface resistance.

Silver has been shown to improve the antibiotic effects of other drugs against both Gram- positive and -negative bacteria. In this study, we investigated the antibiotic potential of cannabidiol (CBD), cannabichromene (CBC) and cannabigerol (CBG) and their acidic counterparts (CBDA, CBCA, CBGA) against Gram-positive bacteria and further explored the additive or synergistic effects of silver nitrate or silver nanoparticles using 96-well plate growth assays and viability (CFUs- colony-forming units). All six cannabinoids had strong antibiotic effects against MRSA with minimal inhibitory concentrations (MICs) of 2 mg/L for CBG, CBD and CBCA; 4 mg/L for CBGA; and 8 mg/L for CBC and CBDA. Using 96-well checkerboard assays, CBC, CBG and CBGA showed full or partial synergy with silver nitrate; CBC, CBDA and CBGA were fully synergistic with silver nanoparticles against MRSA. Using CFU assays, combinations of CBC, CBGA and CBG with either silver nitrate or silver nanoparticles, all at half or quarter MICs, demonstrated strong, time-dependent inhibition of bacterial growth (silver nitrate) and bactericidal effects (silver nanoparticles). These data will lead to further investigation into possible biomedical applications of specific cannabinoids in combination with silver salts or nanoparticles against drug-resistant Gram-positive bacteria.

The production of nanomaterials through environmentally friendly methods is a top priority in the sustainable development of nanotechnology. This paper presents data on the synthesis of silver nanoparticles using an aqueous extract of Sphagnum fallax moss at room temperature. The morphology, stability, and size of the nanoparticles were analyzed using various techniques, including transmission electron microscopy, Doppler laser velocimetry, and UV-vis spectroscopy. In addition, Fourier transform infrared spectroscopy was used to analyze the presence of moss metabolites on the surface of nanomaterials. The effects of different concentrations of citrate-stabilized and moss extract-stabilized silver nanoparticles on cell viability, necrosis induction, and cell impedance were compared. The internalization of silver nanoparticles into both monolayers and three-dimensional cells spheroids was evaluated using dark-field microscopy and hyperspectral imaging. An eco-friendly method for the synthesis of silver nanoparticles at room temperature is proposed, which makes it possible to obtain spherical nanoparticles of 20-30 nm in size with high bioavailability and that have potential applications in various areas of human life.

Molecular detection of nucleic acid plays an important role in early diagnosis and therapy of disease. Herein, a novel and enhanced electrochemical biosensor was exploited based on target-activated CRISPR/Cas12a system coupling with nanoparticle-labeled covalent organic frameworks (COFs) as signal reporters. Hollow spherical COFs (HCOFs) not only served as the nanocarriers of silver nanoparticles (AgNPs)-DNA conjugates for enhanced signal output but also acted as three-dimensional tracks of CRISPR/Cas12a system to improve the cleavage accessibility and efficiency. The presence of target DNA triggered the trans-cleavage activity of the CRISPR/Cas12a system, which rapidly cleaved the AgNPs-DNA conjugates on HCOFs, resulting in a remarkable decrease of the electrochemical signal. As a proof of concept, the fabricated biosensing platform realized highly sensitive and selective detection of human papillomavirus type 16 (HPV-16) DNA ranging from 100 fM to 1 nM with the detection limit of 57.2 fM. Furthermore, the proposed strategy provided a versatile and high-performance biosensor for the detection of different targets by simple modification of the crRNA protospacer, holding promising applications in disease diagnosis.

The preparation of cationic bis(hydrosilane)-coinage-metal complexes by chloride abstraction from the neutral metal chloride precursors with Na[BArF4] is described. Unlike previously reported hydrosilane-stabilized copper and silver complexes, the presented complexes are cationic and feature two bidentate ortho-(silylphenyl)phosphine ligands. These complexes were fully characterized by NMR spectroscopy and X-ray diffraction analysis, revealing that both Si-H bonds are activated by the Lewis acidic cationic metal center. The new complexes were found to be effective in catalytic carbonyl hydrosilylation, leading to the corresponding silyl ethers under mild conditions without the addition of an external base. Combined mechanistic control experiments and quantum chemical calculations support an ionic outer-sphere mechanism, in which a neutral metal alkoxide species instead of a metal hydride is the key intermediate that interacts with the silylcarboxonium ion to generate the silyl ether.

A Gram-stain-positive, rod-shaped, aerobic, motile bacterium, J379T, was isolated from radioactive water spring C1, located in a former silver-uranium mine in the Czech Republic. This slow-growing strain exhibited optimal growth at 24-28 °C on solid media with <1 % salt concentration and alkaline pH 8-10. The only respiratory quinone found in strain J379T was MK-7(H4). C18 : 1 ω9c (60.9 %), C18 : 0 (9.4 %), C16 : 0 and alcohol-C18 : 0 (both 6.2 %) were found to be the major fatty acids. The peptidoglycan contained directly cross-linked meso-diaminopimelic acid. Phylogenetic reconstruction based on the 16S rRNA gene sequences and the core-genome analysis revealed that strain J379T forms a separate phylogenetic lineage within the recently amended order Solirubrobacterales. A comparison of the 16S rRNA gene sequences between strain J379T and other members of the order Solirubrobacterales showed <96 % similarity. This analysis revealed that the closest type strains were Parviterribacter kavangonensis D16/0 /H6T (95.2 %), Capillimicrobium parvum 0166_1T (94.9 %) and Conexibacter arvalis KV-962T (94.5 %). Whole-genome analysis showed that the closest type strain was Baekduia soli BR7-21T with an average nucleotide identity of 78 %, average amino acid identity of 63.2 % and percentage of conserved proteins of 48.2 %. The G+C content of the J379T genomic DNA was 71.7 mol%. Based on the phylogenetic and phylogenomic data, as well as its physiological characteristics, strain J379T is proposed to represent a type strain (DSM 113746T=CCM 9300T) of Svornostia abyssi gen. nov. sp. nov. within the family Baekduiaceae.

Surface-enhanced Raman spectroscopy (SERS) tagging using silica(SiO2)@Ag nanoparticles (NPs) is easy to handle and is being studied in various fields, including SERS imaging and immunoassays. This is primarily due to its structural advantages, characterized by high SERS activity. However, the Ag NPs introduced onto the SiO2 surface may undergo structural transformation owing to the Ostwald ripening phenomenon under various conditions. As a result, the consistency of the SERS signal decreases, reducing their usability as SERS substrates. Until recently, research has been actively conducted to improve the stability of single Ag NPs. However, research on SiO2@Ag NPs used as a SERS-tagging material is still lacking. In this study, we utilized a Raman labeling compound (RLC) to prevent the structural deformation of SiO2@Ag NPs under various conditions and proposed excellent SiO2@Ag@RLC-Pre NPs as a SERS-tagging material. Using various RLCs, we confirmed that 4-mercaptobenzoic acid (4-MBA) is the RLC that maintains the highest stability for 2 months. These results were also observed for the SiO2@Ag NPs, which were unstable under various pH and temperature conditions. We believe that SERS tags using SiO2@Ag NPs and 4-MBA can be utilized in various applications on based SERS because of the high stability and consistency of the resulting SERS signal.