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This study implements research-oriented comprehensive chemistry laboratory teaching by combining fundamental education with scientific research training, thus enhancing talent development and promoting educational reform harmoniously. Silver nanoparticles were synthesized using straightforward inorganic chemical reactions, with the color of the resulting silver nanocolloid solution controlled by varying the bromine/silver ratio. This introduction of surface plasmon resonance characteristics into the experimental curriculum increases the experiment's engagement. The chemical activity of the silver nanoparticles was verified using the classic p-nitrophenol catalytic reaction model. Results indicated that the silver nanoparticles exhibited excellent catalytic performance, approximating first-order reaction kinetics. Additionally, a simple pollutant degradation reactor was constructed using standard laboratory glassware, and homemade silver-embedded filter paper was used for over ten cycles of degradation, achieving a degradation rate of up to 90%. [ABSTRACT FROM AUTHOR]

BACKGROUND: Most of the silver coating materials prepared using active screen plasma technology in the past do not involve the nanotechnology field. The formed silver coating is in a “thin film” form, which is coated on the surface of the substrate, and the distribution of silver particles on the surface is uneven. Its long-term antibacterial ability is challenged. OBJECTIVE: To prepare nano silver coatings capable of being “buried” within stainless steel (SS) substrates using active screen plasma surface modification (ASPSM) and to observe antibacterial activity. METHODS: The nano-silver coating was prepared by ASPSM technique on stainless steel substrate. Three groups of coating samples were prepared by adjusting the bombardment time (1, 2, and 4 hours), which were denoted as 1 h-Ag-ASPSM@SS, 2 h-Ag-ASPSM@SS and 4 h-Ag-ASPSM@SS, respectively. The antibacterial activity of the coatings was analyzed by antibacterial ring test and Gram staining. The antibiotic coating samples of gentamicin combined with vancomycin were prepared by using stainless steel as substrate and were recorded as ACNs. Stainless steel, 2 h-Ag-ASPSM@SS, and ACNs were inserted into Staphylococcus aureus or Pseudomonas aeruginosa suspension, respectively. The long-acting (84 days) antibacterial activity of the samples was analyzed by coating plate method. Bone marrow mesenchymal stem cells were co-cultured with stainless steel, 2 h-Ag-ASPSM@SS, and ACNs, respectively. CCK-8 assay, dead/alive staining, and lactate dehydrogenase activity of cell supernatant were detected. Stainless steel, 2 h-Ag-ASPSM@SS, and ACNs were taken after continuous exposure to Staphylococcus aureus suspension for 12 weeks. The amount of residual viable bacteria on the surface of the material was evaluated by spread plate method. Vancomycin drug sensitive disk method was used to evaluate the resistance of residual live bacteria on the surface of materials. RESULTS AND CONCLUSION: (1) With increasing bombardment time, the diameter of nano silver on the sample surface and the silver content in the coating gradually increased. Among them, the 2 h-Ag-ASPSM@SS exhibited the highest surface silver content while forming uniformly spherical nanoparticles. (2) Antibacterial ring test and Gram staining results demonstrated that compared with 1 h-Ag-ASPSM@SS and 4 h-Ag-ASPSM@SS, the 2 h-Ag-ASPSM@SS exhibited better inhibitory effect on Staphylococcus aureus and pseudomonas aeruginosa. After co-culturing with bacteria for 42 and 84 days, the number of viable bacteria on the spread plate method was significantly lower in the 2 h-Ag-ASPSM@SS group compared to the stainless steel and ACNs groups. After coculturing with Staphylococcus aureus for 84 days and Pseudomonas aeruginosa for 42 days, the number of viable bacteria on the surface of the eluate from the ACNs group was higher than that of the stainless steel group. (3) CCK-8 assay, live/dead staining and lactate dehydrogenase activity of cell supernatant displayed that 2 h-Ag-ASPSM@SS did not have obvious cytotoxicity. ACNs showed obvious cytotoxicity. (4) After co-culture with Staphylococcus aureus for 12 weeks, the residual viable bacteria on the surface of 2 h-Ag-ASPSM@SS group was less than that of stainless steel group, and the residual viable bacteria on the surface of the ACNs group was more than that of stainless steel group. Compared with the stainless steel group, the sensitivity to vancomycin was significantly decreased in the ACNs group (P < 0.001), and there was no significant change in sensitivity to vancomycin in 2 h-Ag-ASPSM@SS group (P > 0.05). (5) The above results indicate that the silver nanoparticle coated stainless steel greatly improves the deposition efficiency of silver nanoparticles on the stainless steel surface and has long-lasting antibacterial properties and good cell compatibility. [ABSTRACT FROM AUTHOR]

Implant infection is one of the most common and serious complications in orthopedics, and it is also an important reason for the failure of implant surgery. When bacteria form a biofilm on the implant surface, it is extremely difficult to be eliminated and attracts more bacteria and fungi. A large number of studies have shown that the use of surface modification technology can effectively reduce the adhesion and accumulation of pathogenic bacteria, thereby preventing peri-implant infection. The formation process of bacterial biofilm on the surface of orthopedic implants and the antibacterial mechanism of metal antibacterial agents were first analyzed. Then, some of the most widely used metal-based inorganic antibacterial coatings at home and abroad and their related preparation processes were reviewed, the problems and improvement methods in the application of these coatings were also discussed, and the development direction of inorganic antibacterial coatings in the future was prospected, such as synergistic antibacterial coatings and bone-promoting antibacterial coatings.

To enhance the conductivity of polyester fabric and broaden its application potential in the realm of flexible electronic devices, the conductive composite polyester fabric was prepared by solution polymerization and magnetron sputtering with aniline and pyrrole as monomers and nano-silver as the target material. The growth model of nano-metal film on the surface of flexible fiber was probed. Additionally, we examined how varing magnetron sputtering times impacted the microstructure, crystallization performance, chemical structure, and electrochemical performance of composite fabric. The results show that the nano silver grown by magnetron sputtering mainly grows on the surface of the flexible fabric substrate in a 'layered-island mode'. As spattering time increases, the nano silver film particles become increasingly uniform; however, excessively long time results in roughness. The metallic silver film shows good uniformity and compactness when the sputtering time is 900 s. The electrochemical performance of the composite fabric can be further improved by magnetron sputtering silver metal. When the sputtering time is 900 s and the current density is 1 mA/cm², the area specific capacitance of the fabric reaches a peak of 67.1 mF/cm², which is approximately 3.3 times higher than that of PANI-PPy/PET. These findings suggest promising applications for functional conductive textiles. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Bone tissue has the function of self-renewal, reconstruction and repair of tissue defects. However, when a large area of severe bone defect occurs, bone grafts or bone substitutes are often needed to reconstruct the defect, which increases the risk of bone infection around the implant. OBJECTIVE: To prepare nanohydroxyapatite/polycaprolactone composite nanofiber scaffolds with different silver concentrations to determine the silver concentration that promotes cell proliferation and has antibacterial properties. METHODS: Nanohydroxyapatite/polycaprolactone composite nanofiber scaffolds with different silver concentrations (0, 0.001, 0.01, 0.1 mol/L) were prepared by using electrospinning technology. The microscopic morphology and elemental composition of scaffolds of four groups were shown by scanning electron microscopy, energy dispersive spectroscopy and transmission electron microscope. MC3T3-E1 osteoblasts were co-cultured with four groups of scaffolds to study the effect of sample scaffolds on the cell proliferation and osteogenic differentiation. Four groups of scaffolds were co-cultured with Staphylococcus aureus (ATCC25923) and Escherichia coli (ATCC25922) to study the antibacterial properties of scaffolds by the formation of antibacterial circle and antibacterial rate. RESULTS AND CONCLUSION: (1) Scanning electron microscopy showed that the four groups of electrospinning films were more continuous and uniform in diameter. The electrospinning filaments displayed a mesh-like structure, in which pore structures of different sizes were dispersed. As the silver-loaded content of the scaffold increased, the diameter of the nanofibers gradually increased. Transmission electron microscope showed that the silver-loaded scaffold nanofibers were uniformly dispersed with black silver nanoparticles, and the particle size diameter was (46±24) nm. (2) CCK-8 assay showed that compared with the unloaded silver scaffolds, silver-loaded 0.001, 0.01 mol/L nanofiber scaffolds could promote osteoblast proliferation. Silver-loaded 0.1 mol/L nanofiber scaffolds inhibited osteoblast proliferation. Nucleus and cytoskeleton staining showed that silver-loaded 0, 0.001, and 0.01 mol/L nanofiber scaffolds facilitated the extension of osteoblast morphology. Silver-loaded 0.1 mol/L nanofiber scaffolds were not conducive to the extension of osteoblast morphology. (3) Alkaline phosphatase staining showed that silver-loaded 0, 0.001, and 0.01 mol/L nanofiber scaffolds were beneficial to osteoblast differentiation, and silverloaded 0.1 mol/L nanofiber scaffolds inhibited osteoblast differentiation. (4) Antibacterial circle experiment showed that the unloaded silver scaffolds had no antibacterial properties. As the silver-loaded content of the scaffold increased, the antibacterial properties of silver-loaded scaffolds increased. Antibacterial rate experiment proved that silver-loaded 0.01 mol/L nanofiber scaffolds had strong antibacterial activity. (5) The results confirm that the silver-loaded 0.01 mol/L nanohydroxyapatite/polycaprolactone composite nanofiber scaffold has both good biological activity and excellent antibacterial properties. [ABSTRACT FROM AUTHOR]

Using glucose as the reducing agent, the nano-silver-graphene composite material (Ag/GR) was synthesized in situ by electroless plating, the structural morphology of the material was characterized and analyzed by X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and Fourier infrared spectrometry (FTIR). The results show that the loading morphology of silver on the graphene surface is the single state that meets the expectation. The average particle size of AgNPs is about 21 nm. At the same time, the electrochemical response of ascorbic acid (AA) on Ag/GR/GCE electrochemical sensors was studied using the electrochemical test methods of cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV). The electrochemical test results show that the Ag/GR composite has the highest response electrochemical signal of 212.9 μA and the lowest resistance of charge transfer of 90.5 Ω. The peak current is about twice that of the graphene electrode (110 μA) and about five times that of the glassy carbon electrode (42.5 μA). Due to the good synergistic effect of AgNPs and graphene, it has obvious electrocatalytic activity for AA. And the anode peak current and concentration show positive correlation linear change trend in the range of 5-120 μmol/L. However, the anode peak current of AA is highly correlated with the natural logarithm of the concentration range from 50 μmol/L to 120 μmol/L. The low limits of detection is 0.06 μmol/L.

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pathogenic microorganism is a serious threat to human health. As a novel kind of antibacterial materials, silver nanoparticles involving their preparation approaches and applications are of great research interest in the field of nanomaterials. This review summarized a summary of synthesis methods of silver nanoparticles, including polysaccharide, Tollens, irradiation, biological and polyoxometalates, which enjoy numerous advantages such as wide range of raw materials, gentle reaction condition, low-cost and environmental-friendly and etc.. Furthermore, based on the antibacterial property of silver nanoparticles, the antibacterial mechanism and applications were described. The development of silver nanoparticles in antibacterial application was also prospected, such as antibacterial coating and antibacterial packaging.

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai University / Shanghai Daxue Xuebao is the property of Journal of Shanghai University (Natural Sciences) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The biological synthesis method is clean, environmental-friendly, low-cost and the experimental condition is mild. This study in vestigated the extracellular biosynthesis of silver nanoparticles by the cell-free culture supernatant of Paenibacillns polymyxa Jaas cd. The silver nanoparticles were characterized in the range of 20 -50 nm, with uniform spherical shape and good dispension by UV-visble spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. The fungicidal activity of different fungicides with Ag NPs against Fusarium oxysporum f. sp. niveum were evaluated by the mycelium growth rate method. The inhibition of different fungicides against GY-16 were enhanced evidently in combination with AgNPs. [ABSTRACT FROM AUTHOR]

Silver nanoparticle colloid was prepared through the reduction of silver nitrate by modified hyperbranched polymer (MHBP) in aqueous solution. The generated silver nanoparticles were characterized by UV-Vis, XRD, Nano-Sizer and TEM. The diameter of silver nanoparticle was around 10 nm and could disperse well in the aqueous solution with excellent stability. Then the silver nanoparticle colloid was diluted in order to treat the silk fabric. The results showed that there were plenty of silver nanoparticles dispersed well on the surface of silk fibers. The treated silk fabric exhibited excellent antibacterial activity. When the silver content of treated silk fabric was 109.80 mg/kg, the bacterial reduction rates against S.aureus and E.coli were 99.46% and 99.25% respectively, and beyond 98% even after washing 50 times [ABSTRACT FROM AUTHOR]