• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.3 no.2
• /
• pp.103-112
• /
• 2017

The combination of nanoparticle with radioisotope could give the in vivo information with high sensitivity and specificity. However, radioisotope labeling of nanoparticle is very difficult and radioisotopes have different physicochemical properties, so the radioisotope selection of nanoparticle should be carefully considered. $^{18}F$ was first option to be considered for labeling of nanoparticle. For the labeling of $^{18}F$ with nanoparticle, Prosthetic group is widely used. Iodine, another radioactive halogen, is often used. Since radioiodine isotopes are various, they can be used for different imaging technique or therapy in the same labeling procedures. $^{99m}Tc$ can easily be obtained as pertechnatate ($^{99m}{TcO_4}^-$) by commercial generator. Ionic $^{68}Ga$ (III) in dilute HCl solution is also obtained by generator system, but $^{68}Ga$ can be substituted for $^{67}Ga$ because of the short half-life (67.8 min). $^{64}Cu$ emits not only positron but also ${\beta}-particle$. Therefore $^{64}Cu$ can be used for imaging and therapy at the same time. These radioactive metals can be labeled with nanoparticle using the bifunctional chelator. $^{89}Zr$ has longer half-life (78.4 h) and is used for the longer imaging time. Unlike different metals, $^{89}Zr$ should use the other chelate such as DFO, 3,4,3-(LI-1,2-HOPO) or DFOB.

• Polymer(Korea)
• /
• v.38 no.2
• /
• pp.150-155
• /
• 2014

Polycaprolactone (PCL) is a synthetic biodegradable polymer with excellent mechanical properties. $TiO_2$ (titanium dioxide) has a hydrophilic, high density and excellent biocompatibility. In this work, we produced three-dimensional porous scaffolds with PCL and $TiO_2$ nanoparticles using a salt-leaching method. Physical properties of the scaffolds were analyzed by FE-SEM, FTIR, TGA and compressive strength. Interestingly, the addition of $TiO_2$ nanoparticles decreased the water absorption and swelling ratio of the porous scaffolds. However, the compressive strength was increased by $TiO_2$. CCK-8 assay, which is generally used for the analysis of cell growth, shows that $TiO_2$ nanoparticles have no cytotoxicity. Taken together, we suggest that the PLC/$TiO_2$-scaffold can be used for biomedical applications.

• Proceedings of the KSME Conference
• /
• 2007.05b
• /
• pp.1906-1911
• /
• 2007

It has been well known that pool boiling CHF in nanofluids compared to pure water significantly increase due to the deposition of nanoparticles on heater surface. This study concerns the characteristics of the nanoparticle deposition layer and its influence on CHF. Pool boiling experiments were carried out with 0.01vol.% water-$TiO_2$ nanofluids to obtain various nanoparticle-deposited heaters. CHF on the prepared heaters was measured during pool boiling in pure water. The heater surfaces were visualized using scanning electron microscope (SEM) and also characterized using contact angle and capillarity. The results showed that the CHF enhancement in nanofluids was completely dependent upon the structural and physicochemical characteristics of the nanoparticle deposition layer.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1542-1546
• /
• 2003

Nanotechnology is an important challenge, for which nanoparticle manipulation plays an important role in the assembly of nano elements. In this study, the dynamic equation of system plant is established by van der Waals force, friction, capillary forces etc. To push nanoparticles, strain gauges are used as sensors to actuate an X-Y stage in an atomic force microscopy system. A strategy of pushing nanoparticles is developed based on sliding mode control. Moreover, afuzzy controller is responsible for compensating tip-particle contact loss according to feedback signals of a laser-detector system. According to position control result, experimental results of gold nanoparticle manipulation are presented.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.210-214
• /
• 2007

Silicon nanoparticles are widely studied as a material with great potential for wide applications. For application to present industry, it should be easy to control the characteristics of nanoparticle including the size and structure. In this paper, we investigated the formation of Si nanoparticle using pulse plasma technology. Plasma technology is already quite common in device industry and the size of nanoparticle can be easily controlled according to plasma pulse duration. An inductively-coupled plasma chamber with RF power (13.56 MHz) was used with DC-biased grid $(-200\sim+200\;V)$ installed above the substrate. In order to measure the shape and size of nanoparticle, TEM was used. It was found that the size of nanoparticles can be controlled well with the plasma pulse duration and the collection efficiency is increased with the use of either negative or positive DC-bias.

• Journal of Radiopharmaceuticals and Molecular Probes
• /
• v.1 no.1
• /
• pp.46-52
• /
• 2015

Herein we present the synthesis of $^{68}Ga$-labeled gold nanoparticles for in vivo PET imaging. A novel chelator DTPA-Cys was easily prepared from diethylenetriaminepentaacetic dianhydride in high yield. The ${\alpha}_v{\beta}_3$ integrin receptor targeted gold nanoparticle probe was synthesized by using DTPA-Cys, polyethylene glycol and cRGD peptide. $^{68}Ga$ labeling of cRGD conjugated gold nanoparticle was carried out at $40^{\circ}C$ for 30 min. Observed radiochemical yield was more than 75% as determined by radio-TLC and the probe was purified by centrifugation. In vitro stability test showed that 90% of $^{68}Ga$-labeled gold nanoparticle probe was stable in FBS for 1 h. Those results demonstrated that $^{68}Ga$-labeled gold nanoparticle could be used as a potentially useful probe for specific tumor imaging.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.391-392
• /
• 2013

반도체 집적회로의 고집적화 및 고성능화를 위한 기본 소자(MOSFET)의 미세화 및 단위공정의 물리적 한계를 극복하기 위해 기존의 Top-down 방식에서 buttom-up 방식의 공정에 대한 연구가 진행되고 있다. 그 중 nanoparticles를 이용한 나노소자 제작 연구가 이루어지고 있다. 하지만 이러한 nanoparticles를 이용한 나노소자의 제작에 있어서 원하는 위치에 nanoparticles를 배열하고 정렬하는데 어려움을 겪고 있다. 이 문제를 해결하기 위해서 자기조립 특성을 가지고 있는 DNA분자와 기능화를 통하여 표면에 positive charge를 띄고있는 Gold nanoparticles를 상호결합 시키는 실험을 하였다. Au-DNA nanowire는 backbone에 있는 phosphate부분에서 negative charge를 띠고 있는 DNA와 positive charge를 띠고 있는 Gold nanoparticles가 결합하는 원리로 형성된다. 그렇지만 Gold particles를 표면이 아닌 DNA에만 붙이는 것은 아직 해결해야 할 부분으로 남아있다. 본 연구에서는 이 문제를 해결하기 위하여 pH 조절을 통하여 기능화된 Gold particles의 charge의 변화를 주고 이를 Zeta potential 측정기로 측정한 후에 이 particles와 DNA를 결합시켜서 FE-SEM과 AFM 으로 확인하는 실험을 하였다.

• Journal of Integrative Natural Science
• /
• v.3 no.4
• /
• pp.197-201
• /
• 2010

Dihydrotetraphenylgermole has been synthesized from the reduction of dichlorotetraphenylgermole with lithiumaluminiumhydride. UV-Vis absorption and photoluminescence was measured by using UV-Vis and fluorescence spectroscopy. Nanoparticles of dihydrotetraphenylsilole were synthesized from the mixture solution of water and THF. Photoluminescence behavior of organogermanium nanoparticle was investigated at various water fractions. Critical fraction of water to form organogermanium nanoparticles was 60%. Photoluminescence intensity of organogermanium nanoparticle was increased as the concentration of organogermanium nanocolloids increased. Photoluminescence efficiency of organogermanium nanoparticle at 90% water fraction increased about 100 times compared to that of molecular state.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.18 no.5
• /
• pp.478-483
• /
• 2005

In this paper, we synthesized 10 to 20 nm diameter NiFe nanoparticles and nanoparticle films utilizing supersonic jet deposition of nanoparticle aerosols generated by laser ablation of $30\;to\;45{\mu}m$ diameter permalloy $(Ni_{81}Fe_{19} \;at\;{\%})$ microparticles. The component and composition of the nanoparticles were characterized by an energy dispersive X-ray spectroscopy. The morphology of the nanoparticles and nanoparticle films was analyzed by a high-resolution transmission electron microscopy and a scanning electron microscopy, respectively. The experimental results showed that the nanoparticles and nanoparticle films have remarkable properties with an excellent preservation of the composition of feedstock permalloy microparticles. The purpose of the present work is to present details on the composition and nanostructural characterizations for NiFe nanoparticles and nanoparticle films prepared by laser ablation of microparticles (LAM).

• Microbiology and Biotechnology Letters
• /
• v.39 no.1
• /
• pp.1-8
• /
• 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.