• Journal of Veterinary Clinics
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• v.34 no.6
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• pp.425-428
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• 2017

Silver nanoparticles have marked antimicrobial effects on several pathogens and have been used to control bacterial growth in humans. In the present study, we evaluated the antimicrobial efficacy of silver nanoparticles against the common causative pathogens of canine otitis external through counting of colony forming units. Silver nanoparticles showed significant dose-dependent antimicrobial effects on pathogens. In addition, we conducted antimicrobial susceptibility tests and compared the antimicrobial efficacy of silver nanoparticles. Microorganisms with a high resistance to antibiotics were also resistant silver nanoparticle with low concentration ($5{\mu}g/mL$). However, in high concentration ($15{\mu}g/mL$), almost 100% reduction in the number of CFUs of these pathogens was observed.

• Journal of the Korean Chemical Society
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• v.20 no.4
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• pp.280-289
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• 1976

The silver selenide electrode has been prepared and its properties as an indicating electrode for silver ion have been investigated. Epoxy resin was used as a filler of silver selenide electrode. Silver metal plate was directly connected with the membrane of the electrode and the silver paste was used as its binder. The sintered electrode was more sensitive and stable than the pressed electrode, and the silver selenide electrode more sensitive than the silver sulfide electrode to silver ion. The linear relationship between the electrode potential and logarithmic concentration of silver ion has been observed down to 10-6 M for the electrode. Several heavy metal ions except mercuric ion did not interfere this linearity, but halide, cyanide, and thiocyanate ions did intensively interfere owing to the formation of silver compounds and complexes. This electrode has been applied to the potentiometric titration for determining halide ion. It is concluded that interferences from ,$CN^-, SCN^-, S^-, I^-, Br^-, Cl^- and Hg^{2+}$ ions are detrimental to the practical use of the electrodes for measuring pAg.

• Toxicological Research
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• v.28 no.3
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• pp.139-141
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• 2012

Silver nanoparticles (size: $7.9{\pm}0.95$ nm, dosage: 250 mg/kg) were orally administered to pregnant rats. At 4 days after parturition, four pups were randomly selected (one pup from one dam) and silver level in liver, kidney, lung and brain was determined by ICP-MS and electron microscope. As results, silver nanoparticles highly accumulated in the tissues of the pups. Silver level in the treated group was $132.4{\pm}43.9$ ng/g in the kidney (12.3 fold compared to control group), $37.3{\pm}11.3$ ng/g in the liver (7.9 fold), $42.0{\pm}8.6$ ng/g in the lung (5.9 fold), and $31.1{\pm}4.3$ ng/g in the brain (5.4 fold). This result suggested that the possible transfer of silver nanoparticles from pregnant dams to the fetus through mainly placenta.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.251-257
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• 2009

Recently, there is much interest in the antimicrobial activity of silver since silver has known to be safe and effective as a disinfectant or an antimicrobial agent against a broad spectrum of microorganisms. Although silver has been applied to various kinds of products due to the effective antimicrobial activity, the quantitative antimicrobial activity or detailed mechanism of silver is not clearly investigated yet, causing the controversy and confusion. In this review paper, we summarized the characteristics, antimicrobial activities and mechanisms, synergistic effects with other antimicrobials, and applicability of silver.

• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.202-206
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• 2004

The objectives of this study are to investigate the relationship between the silver ion concentrations released from the point-of-use(POU) water purification devices installed silver impregnated activated carbon filters and the antibacterial activities against HPC bacteria. Total of 68 POU devices were tested. The concentrations of the eluted silver ion from the silver impregnated activated carbon filter showed the range from $4\;{\mu}g/L$ to $386\;{\mu}g/L$, and the HPC bacteria were found to diversely grow within the range 0-5,200 cfu/mL. The average silver concentrations released from UF units system and RO units system were $30\;{\mu}g/L$ and $73\;{\mu}g/L$, respectively. And the number of colonies were reduced significantly as the elution levels of silver exceeded $100\;{\mu}g/L$, however silver ions below the concentration of $100\;{\mu}g/L$ were not particularly effective for eradicating HPC bacteria from water.

• The Journal of Korean Physical Therapy
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• v.7 no.1
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• pp.61-67
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• 1995

The silver cation has broad-spectrum antibiotic activity toward Gram-positive, Gram-negative, fungal. aerobic and anerobic micro-organisms. Silver has been used to care of infected wound. pyogenic arthritis, and chronic osteomyelitis. The purpose of this study was to determine whether pure silver wire iontophoresis using milliamperage direct current has an inhibitory effect on growth in vitro of 3 different species of bacteria-Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Using agarose based media, silver iontophoresis performed at 0, 1, 2, 4, 8 mA for 15 minutes. All experiments were performed in triplicate. Following iontophoresis, inhibition zone width of bacterial growth was measured with calliper. The inhibition of bacterial growth occured at the anodal silver electrode. Inhibition zone width of bacterial growth was significantly increased in all three bacterial species (p<0.05). Between bacterial species, inhibition zone width was not significantly different. Inhibition gone and amperage showed a highly significant positive linear relationship (p<0.001). The result of this study showed that pure silver wire iontophoresis with milliamperage direct current, as well as microamperage direct current, can inhibit bacterial growth in vivo.

• Macromolecular Research
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• v.17 no.9
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• pp.688-696
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• 2009

In this study, a new class of polyurethane (PU) nanofibers containing silver (Ag) nanoparticles (NPs) was synthesized by electrospinning. A simple method that did not depending on additional foreign chemicals was used to self synthesize the silver NPs in/on PU nanofibers. The synthesis of silver NPs was carried out by exploiting the reduction ability of N,N-dimethylformamide (DMF), which is used mainly to decompose silver nitrate to silver NPs. Typically, a sol-gel consisting of $AgNO_3$/PU was electrospun and aged for one week. Silver NPs were created in/on PU nanofibers. SEM confirmed the well oriented nanofibers and good dispersion of pure silver NPs. TEM indicated that the Ag NPs were 5 to 20 nm in diameter. XRD demonstrated the good crystalline features of silver metal. The mechanical properties of the nanofiber mats showed improvement with increasing silver NPs content. The fixedness of the silver NPs obtained on PU nanofibers was examined by harsh successive washing of the as-prepared mats using a large amount of water. The results confirmed the good stability of the synthesized nanofiber mats. Two model organisms, E. coli and S. typhimurium, were used to check the antimicrobial influence of these nanofiber mats. Subsequently, antimicrobial tests indicated that the prepared nanofibers have a high bactericidal effect. Accordingly, these results highlight the potential use of these nanofiber mats as antimicrobial agents.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.1
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• pp.80-87
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• 2024

Silver diamine fluoride, which can arrest dental caries, is alkaline and may cause mild soft tissue irritation. Water-based silver fluoride has a neutral pH, which is closer to the physiological range, and is biocompatible for use in the oral environment. This study aimed to evaluate the effect of water-based silver fluoride on remineralizing early enamel lesions by comparing it with other fluoride agents through microhardness and quantitative light-induced fluorescence measurements. An in vitro study with intact bovine incisors was performed. Artificial enamel lesions were induced and subjected to microhardness and quantitative light-induced fluorescence testing. Specimens were randomly divided into 4 groups for treatment. The specimens in group I were treated with water-based silver fluoride and potassium iodide, group II with silver diamine fluoride and potassium iodide, group III with sodium fluoride varnish, and group IV with distilled water. After 8 days of pH cycling, the specimens were subjected to microhardness and quantitative light-induced fluorescence testing. Water-based silver fluoride and silver diamine fluoride showed the greatest increases in microhardness and quantitative light-induced fluorescence, with no significant differences between the two. Sodium fluoride varnish also exhibited a significant increase in microhardness and quantitative light-induced fluorescence, but the differences were smaller than those for water-based silver fluoride and silver diamine fluoride. Water-based silver fluoride is considered useful in a clinical setting for remineralizing enamel lesions, with the advantages of no risk of tissue burn and improved taste and smell.

• Journal of the Korean Society of Industry Convergence
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• v.14 no.3
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• pp.101-104
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• 2011

In this study, the experiments for surface enhancement of silver surfaces were done, where we checked the characteristics of silver surfaces made by Tollen's method. The surface enhancement of Quinoline was analyzed by three kind of silver mirror substrates. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. Finally, we deduced that the adsorption orientation of quinoline was little tilted flat to the silver mirror surfaces by using of the surface selection rules.

• Journal of the Korean Chemical Society
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• v.6 no.2
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• pp.122-124
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• 1962

The silver halide precipitate tends to separate in curdy form of flocculated colloid when it is precipitated by direct mixing of reactant solutions. This type of precipitate has a great tendency to adsorb or occlude foreign ions in the solution.When silver halide in precipitated from homogeneous solution using the slow hydrolysis of Alkyl halide or Ally halide, the precipitate becomes dense, filterable and uniform in particle size which is very advantageous in gravimetric analysis.We found that silver halide precipitates obtained from homogeneous solution with hydrogen halide formed by the hydrolysis of alkyl halide do not give the color change with fluorescein as adsorption indicater, while silver halide precipitates obtained by direct mixing method give sharply pink color which appear to be uniformly distributed through the solution in silver ion excess.