• Korean Chemical Engineering Research
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• 제55권4호
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• pp.556-560
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• 2017

A hemoglobin/silver nanoparticle heterolayer was fabricated for bioelectronic device with electrochemical signal-enhancement effect. As a device element, a hemoglobin, the metalloprotein, contained the heme group that showed the redox property was introduced for charge storage element. For electron transfer facilitation, a silver nanoparticle was introduced for electrochemical signal facilitation, the hemoglobin was immobilized onto Au substrate using chemical linker 6-mercaptohexanoic acid (6-MHA). Then, the silver nanoparticle was immobilized onto fabricated hemoglobin/6-MHA heterolayers by layer-by-layer (LbL) method. The surface morphology and surface roughness of fabricated heterolayer were investigated by atomic force microscopy (AFM). The redox property of hemoglobin/silver nanoparticle heterolayer was investigated by a cyclic voltammetry (CV) experiment for obtaining an oxidation potential and reduction potential. Moreover, for the assessing charge storage function, a chronoamperometry (CA) experiment was conducted to hemoglobin/silver nanoparticle-modified heterolayer electrode using oxidation and reduction potentials, respectively. Based on the results, the fabricated hemoglobin/silver nanoparticle heterolayer showed that an increased charge storage effect compared to hemoglobin monolayer-modified electrode.

• 한국미생물·생명공학회지
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• 제39권1호
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• pp.1-8
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• 2011

The antimicrobial effects of silver (Ag) ion or salts are well known. Recently, silver nanoparticle is attracting an interest in a wide variety of fields since it has been known to be safe and effective as an antimicrobial agent against a broad spectrum of microorganisms. Although silver nanoparticle has been applied to various kinds of products owing to its potent antimicrobial activity, the effects of silver nanoparticle on microorganisms and antimicrobial mechanism have not been revealed clearly. In this paper, we summarized the characteristics, antimicrobial activities and mechanisms, cytotoxicity and applicability of silver nanoparticle.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.961-964
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• 2014

• 한국해양환경ㆍ에너지학회지
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• 제12권4호
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• pp.302-306
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• 2009

이 연구에 사용된 9종류의 나노입자는 직경 100 nm 이하의 크기를 가진 입자로, 알테미아 cyst가 nauplius로 부화되는 과정에서 어떠한 영향을 미치는지 살펴보았다. 24시간 경과 후 나노입자를 첨가하지 않은 대조구에서는 82%가 nauplius로 부화하였다. 20 mg/L 농도에서는 AGZ020, Nano silver, P-25, Sb, 및 SnO 나노입자가 각각 18%, 20%, 13%, 50% 및 0%의 부화율을 보여 유해성이 큰 것으로 나타났으나, Ag-$TiO_2$, In, Sn, 및 Zn 나노입자에서는 각각 75%, 60%, 73% 및 73%로 대조구에 비해 유해성을 가졌지만, AGZ020, Nano silver, P-25, Sb, 및 SnO 나노입자에 비해 상대적으로 미약한 것으로 나타났다. 이는 나노입자가 가지고 있는 성분에 따라서 차이가 났다. AGZ020, Nano silver 및 P-25 나노입자는 은(Ag)이 2% 함유되어 항균제로서 널리 사용되어지고 있으며, 산소를 결합시킨 SnO 나노입자는 광촉매제로 사용되고 있다. 이들 나노입자들은 현재 가전, 기능성 화장품, 항균제 및 광촉매제 등 사용이 일반화되어 수중환경으로 유입될 가능성이 높아지고 있다. 이에 따라 수중생태계에 점차 영향을 줄 가능성이 높기에, 나노입자가 가지는 잠재적 위험성을 지속적으로 연구해야 할 것이다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.137-141
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• 2008

이 연구에 사용된 9종류의 나노입자는 직경 100nm 이하의 크기를 가진 입자로, 알테미아 cyst가 nauplius로 부화되는 과정에서 어떠한 영향을 미치는지 살펴보았다. 24시간 경과 후 나노입자를 첨가하지 않은 대조구에서는 82%가 nauplius의 부화하였다. 20mg/L 농도에서는 AGZ020, Nano silver, P-25, Sb, 및 SnO 나노입자가 각각 18%, 20%, 13%, 50% 및 0%의 부화율을 보여 유해성이 큰 것으로 나타났으나, Ag-$TiO_2$, In, Sn, 및 Zn 나노입자에서는 각각 75%, 60%, 73% 및 73%로 대조구에 비해 유해성을 가졌지만, AGZ020, Nano silver, P-25, Sb, 및 SnO 나노입자에 비해 상대적으로 미약한 것으로 나타났다. 이는 나노입자가 가지고 있는 성분에 따라서 차이가 났다. AGZ020, Nano silver 및 P-25 나노입자는 은(Ag)이 2% 함유되어 항균제로서 널리 사용되어지고 있으며, 산소를 결합시킨 SnO 나노입자는 광촉매제로 사용되고 있다. 이들 나노입자들은 현재 가전, 기능성 화장품, 항균제 및 광촉매제 등 사용이 일반화되어 수중환경으로 유입될 가능성이 높아지고 있다. 이에 따라 수중생태계에 전파 영향을 준 가능성이 높기에, 나노입자가 가지는 잠재적 위험성을 지속적으로 연구해야 할 것이다.

• 방사선산업학회지
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• 제4권4호
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• pp.353-357
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• 2010

Silver nanoparticles (AgNPs) can be used in the areas such as integrate circuit, cell electrode and antimicrobial deodorant. In this study, AgNPs have been prepared by using $AgNO_3$ aqueous solution in the carboxymethyl cellulose (CMC) hydrogel. CMC powders were dissolved in deionized water, and then irradiated by a gamma-ray with a radiation dose of 50 kGy to make CMC hydrogel. CMC hydrogels were dipped into $1.0{\times}10^{-2}M$ $AgNO_3$ solution for 1 hour. After that, the swollen hydrogels were irradiated by gamma-ray for the formation of AgNPs. The characteristics of silver nanoparticles in the CMC hydrogels were monitored by UV-Vis and the morphological study and dispersed coefficient of particles were investigated by FE-SEM/EDX. It was observed that the sodium salt in the CMC is crucial to the formation of silver nanoparticle. Finally, antibacterial tests indiacted that the hydrogel containing silver nanoparticle has antibacterial activity.

• 멤브레인
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• 제29권5호
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• pp.246-251
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• 2019

올레핀/파라핀 분리를 위해 silver nanoparticle을 운반체로 이용하는 촉진수송막이 최근 많은 관심을 받고 있다. 기존 연구에서는 silver nanoparticle의 전구체로서 $AgBF_4$가 사용되어 왔다. 하지만 상대적으로 고가에 속하는 $AgBF_4$는 상업화에 적합하지 않기 때문에 비교적 저렴한 $AgClO_4$를 전구체로 이용해 제조된 silver nanopaticle를 활용해서 PEBAX-5513/AgNPs(전구체: $AgClO_4$)/7,7,8,8-tetracyanoquinodimethane (TCNQ) 복합막이 제조되었다. 그러나 여러 조성의 복합막이 제조되었으나 올레핀 분리성능은 관찰되지 않았다. FT-IR 분석 결과는 PEBAX-5513 고분자 내에서 silver nanoparticle이 형성되고 TCNQ에 의해 표면이 양극성화 되는 것을 확인하였지만 형성된 silver nanoparticle이 안정화 되지 못한 것으로 분석되었다. 이러한 결과들을 통해 은염 전구체의 음이온이 올레핀/파라핀 분리막에서 중요한 역할을 하는 것으로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제26권5호
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• pp.791-794
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• 2005

A visible photochemistry of maleic to fumaric acid adsorbed on silver nanoparticle surfaces was investigated as probed by SERS using a simple flow method. Photoisomerization of maleic to fumaric acid was consecutively observed in the condition of various flow rates, which varied the exposure time of laser beam. The sequential SERS spectra of maleic acid indicated that the photochemical isomerization and desorption took place simultaneously on silver nanoparticle surfaces as a function of laser fluency and wavelength. For 530.9nm laser line excitation, the rate constant coefficients were obtained with a = 5.9 $sec^{-1}$ mW for isomerization and b = 13.9 $sec^{-1}$ mW for desorption, which $k_1\;=\;aI^n\;and\;k_2\;=\;bI^m$. Both reactions were one photon process (n = 1, m = 1) of a visible light and relatively fast process whose decay time was in the range of milli-second for 50 mW laser power. The rate of photochemical reaction increased on going toward the blue and photodesorption was a dominant process. A simple flow method used in this study was very useful to study a relatively fast photochemical reaction of molecules adsorbed on silver nanoparticle surfaces.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.221-226
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• 2012

DNA-functionalized silver and silver/gold bimetallic nanoparticle superstructure probes with controllable sizes and optical properties are synthesized using monothiol DNA and dithiothreitol. The superstructures exhibit a very narrow size distribution, which can be easily controlled by balancing the ratio of dithiothreitol and DNA. These superstructures assemble reversibly in a highly cooperative manner, and are SERS active. Multiplexed colorimetric detection of DNA targets using these superstructure probes has been demonstrated to identify three different DNA target sequences that are associated with three lethal diseases, respectively.

• Elastomers and Composites
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• 제54권3호
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• pp.252-256
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• 2019

Fullerene oxide[$C_{60}(O)_n$, ($n{\geq}1$)] was synthesized by dissolving fullerene[$C_{60}$] and 3-chloroperoxybenzoic acid in toluene under refluxing condition for 5 h. Hybrid fullerene oxide-silver nanoparticle composites were synthesized by dissolving fullerene oxide and silver nitrate[$AgNO_3$] in diethylene glycol under ultrasonic irradiation for 3 h. The synthesized hybrid nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, and ultraviolet-visible[UV-vis] spectroscopy. The catalytic activity for the reduction of various nitroanilines[NAs] was identified by UV-vis spectrophotometer. The efficiency of the catalytic reduction by the synthesized hybrid nanocomposites has an order of 4-NA > 2-NA > 3-NA.