• Proceedings of the PSK Conference
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• 2002.10a
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• pp.409.1-409.1
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• 2002

For the development of a biocompatible nano-scale drug carrier. hydrophilic polysaccharide pullulan was hydrophobized by the conjugation with fatty acid. The synthesized polymers were characterized by the measurements of fourier transform infrared (FT -IR) spectroscopy and 1H -nuclear magnetic resonance (NMR) spectroscopy. In aqueous solution. hydrophobically modified puliulan was self-assembled and structured into the core-shell type nanoparticles. (omitted)

• Fibers and Polymers
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• v.3 no.1
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• pp.14-17
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• 2002

Development of a novel fixed site carrier membrane (FCM), supported by PET fabric for metal ion separation is reported. The membranes were prepared by dipping PET fabric into the methylene chloride solution of Poly(5-vinyl-m-phe-nylene-m'-phenylene-32-crown-10) (P(VCE)), a polymeric metal ion carrier. It was found that the flux of mono-valent metal ion transported across the membrane is signif=cantly differed from each other and the flux decreases in the order $Cs^+$>$Rb^+$>$K^+$>$Na^+$>$Li^+$ irrespective to the anion except perchlorate anion. It was explained in terms of the stability of the complex, formed by crown ether unit of the P(VCE) and the various metal ions, meanwhile, the lower rate of transport in the presence of perchlorate anion was ascribed to its low hydrophilicity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.350-355
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• 1998

Dysprosium monotitanate $(Dy_2TiO_5)$ powder was synthesized by a simple mixed-oxide ceramics process using ethylene glycol (EG). Ethylene glycol, as the organic carrier for the metal cations, was used for polymerization mechanism. The successful used of a non-chelating polymer for the mixed-oxide ceramic process indicated that cation chelation is not the only route for creating stable ceramic precursors. Characterization of the powders by various thermal analysis, microscopy, and diffraction methods has been carried out.

• Journal of Biomedical Engineering Research
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• v.38 no.1
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• pp.43-48
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• 2017

Chemotherapy, radiation therapy, and surgery are major methods to treat cancer. However, current cancer treatments report severe side effects and high recurrences. Recent studies about engineering nanoparticles as a drug carrier suggest possibilities in terms of specific targeting and spatiotemporal release of drugs. While many nanoparticles demonstrate lower toxicity and better targeting results than free drugs, they still need to improve their performance dramatically in terms of targeting accuracy, immune responses, and non-specific accumulation at organs. One possible way to overcome the challenges is to make precisely controlled nanoparticles with respect to size, shape, surface properties, and mechanical stiffness. Here, we demonstrate $500{\times}200nm$ discoidal polymeric nanoconstructs (DPNs) as a drug delivery carrier. DPNs were prepared by using a top-down fabrication method that we previously reported to control shape as well as size. Moreover, DPNs have multiple payloads, poly lactic-co-glycolic acid (PLGA), polyethylene glycol (PEG), lipid-Rhodamine B dye (RhB) and Salinomycin. In this study, we demonstrated a potential of DPNs as a drug carrier to treat cancer.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1219-1224
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• 2005

We prepared lead ion-selective PVC membranes that were based on N,N'-bis-thiophene-2-ylmethylene-ethane-1,2-diamine as a membrane carrier. The membrane electrode has a linear dynamic range between 1.0 ${\times}$ $10^{-5}$ and 1.0 ${\times}$ $10^{-1}$ M with a Nernstian slope of 29.79 mV per decade, and its detection limit was 2.04 ${\times}$ $10^{-6}$ M at room temperature. The potentiometric response is independent of the pH of the solution in the pH range of 5-7. The proposed electrode revealed good selectivity and response for $Pb^{2+}$ over a wide variety of other metal ions in pH 5.0 buffer solutions, and there was good reproducibility of the base line on the subsequent measurements. The membrane electrode has a relatively fast response time, satisfactory reproducibility and a relatively long life time.

• Membrane Journal
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• v.14 no.4
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• pp.263-274
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• 2004

The polymeric membrane, a component of battery devices such as Li-ion battery (LIB) and Li-polymer battery (LPB), is a typical material in which the carrier mobility dominates the battery performance. In this paper, the state-of-the-art of membranes for secondary battery is described in terms of membrane properties. Several prerequisites, which are related to stability of battery devices, are discussed to design and prepare suitable polymeric membranes. In addition, physical requirements of membranes and their measurement methods are described to develop applicable polymeric membranes in membrane preparation processes.

• Archives of Pharmacal Research
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• v.27 no.5
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• pp.562-569
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• 2004

Self-assembling nanospheres of hydrophobized pullulan have been developed. Pullulan acetate (PA), as hydrophobized pullulan, was synthesized by acetylation. Carboxymethylated poly(ethylene-glycol) (CMPEG) was introduced into pullulan acetate (PA) through a coupling reaction using N, N'-dicyclohexyl carbodiimide (DCC). A synthesized PA-PEG-PA (abbreviated as PEP) conjugate was confirmed by Fourier transform-infrared (FT-IR) spectroscopy. Since PEP conjugates have amphiphilic characteristics in aqueous solution, polymeric nanoparticles of PEP conjugates were prepared using a simple dialysis method in water. From the analysis of fluorescence excitation spectra primarily, the critical association concentration (CAC) of this conjugate was found to be 0.0063 g/L. Observations by scanning electron microscopy (SEM) showed the spherical morphologies of the PEP nanoparticles. The particle size distribution of the PEP conjugates was determined using photon correlation spectroscopy (PCS) and the intensity-average particle size was 193.3 ${\pm}$ 13.53 nm with a unimodal distribution. Clonazepam (CNZ), as a model drug, was easy to entrap into polymeric nanoparticles of the PEP conjugates. The drug release behavior was mainly diffusion controlled from the core portion.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1593-1596
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• 2006

The polymeric membrane electrodes based on N,N'-bis-pyridin-2-ylmethylene-naphthalene-1,8-diamine as an ion carrier were prepared and tested for the copper-ion selective electrode. The membrane has a linear dynamic range between $10^{-6}$ and $10^{-2}$ M with a Nernstian slope of 29.6 mV per decade, and its detection limit was $10^{-5.62}$M. The potentiometric response is independent of the pH range of 3-5. The proposed electrode showed good selectivity and response for $Cu^{2+}$ over a wide variety of other metal ions in pH 4.0 buffer solutions.

• Journal of Powder Materials
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• v.10 no.5
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• pp.310-317
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• 2003

Two-component ceramic (alumina-zirconia) composites were fabricated by a soft-solution process in which polyethylene glycol (PEG) was used as a polymeric carrier. Metal salts and PEG were dissolved in ethyl alcohol without any precipitation in 1:1 volume ratio of alumina and zirconia. In the non-aqueous system, the flammable solvent made explosive, exothermic reaction during drying process. The reaction resulted in formation of volume expanded, porous precursor powders by a vigorous decomposition of organic components in the precursor sol. The PEG content affected the grain size of sintered composites as well as the morphology of precursor powders. The difference of microstructure in sintered composite was attribute to the solubility and homogeneity of metal cations in precursor sol. At the optimum amount of the PEG polymer, the metal ions were dispersed effectively in solution and a homogeneous polymeric network was formed. It made less agglomerated particles in the precursor sol and affected on uniform grain size in sintered composite.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.180-180
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• 2006

A novel preparation method for core/shell nanoparticles with protein drug-loaded lipid core was designed and characterized. The lipid core is composed of lecithin and protein drug and the polymeric shell is composed of Pluronics (poly (ethylene oxide)-poly (propylene oxide)-poly(ethylene oxide) triblock copolymer, F-127 For the application of core/shell nanoparticles as a protein drug carrier, lysozyme and Vascular Endothelial Growth Factor (VEGF) were loaded into the core/shell nanoparticles by electrostatic interaction and the drug release pattern was observed by manipulating the polymeric shell.