• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.160-160
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• 2002

• Journal of Photoscience
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• v.1 no.1
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• pp.53-59
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• 1994

Molecular orientation and polarity of solubilization site of dipolar azobenzenes solubilized in micellar solutions are discussed. The polarity of solubilization was estimated by using Taft $\pi$$^*$ scale with linear solvation energy relationship, $\Delta$E=$\Delta$E$_0$ + S($\pi$$^*$ + d$\delta$)+a$\alpha$ + b$\beta$. Hydrogen bonding effects were taken into account for the estimation of micropolarity. The polarity that azobenzenes experienced in the miceliar solutions was close to water which represented that the azobenzenes were mostly solubilized at the interface. For the orientations of azobenzenes were concerned, the nitro group of NPNOH faced the interface and the hydroxy group of NPNO$^-$ located at the interfacial area.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.54-55
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• 2006

Polymeric micelles, supramolecular assemblies of block copolymers, are useful nanocarriers for the systemic delivery of drugs and genes. Recently, novel polymeric micelles with various functions such as the targetability and stimuli-sensitivity have been emerged as promising carriers that enhance the efficacy of drugs and genes with minimal side effects. This presentation focuses our recent approach to the preparation of functional block copolymers that are useful for constructing smart micellar delivery systems in advanced therapeutics, including chemo-gene therapy. Particular emphasis is placed on the characteristic behaviors of intracellular environment-sensitive micelles that selectively exert drug activity and gene expression in live cells.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.267-270
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• 2004

• Proceedings of the Membrane Society of Korea Conference
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• 2004.11a
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• pp.271-274
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• 2004

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.163-170
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• 1993

The effect of substrate micellization on the hydrolysis rate in the production of lysopho-sphatidylcholine (LPC) from phosphatidylcholine (PC) using hog pancreas phospholipase A2(PLA2) was studied. The optimal temperature and pH for the reactions in aqueous phase was found 42C and 7.2, respectively. For a given PC concentration, initial reaction rate was progressively increased with the addition of sodium deoxycholate (DOC), which could transform the bilayer of phospholipids into micellar structure.

• YAKHAK HOEJI
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• v.28 no.3
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• pp.161-167
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• 1984

To improve the solubility properties of indomethacin, a poorly water-soluble drug, some attempts were made with surfactants, such as sodium deoxycholate, sodium laurylsulfate and polysorbate-80. The enhancement effect in solubility was found to be due to the micellar solubilization and dependent on the concentration of surfactants, pH and temperature. The mechanism of interaction was suggested to be attributed to the formation of mixed micelles between the drug and solubilizers.

• Journal of Ginseng Research
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• v.8 no.2
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• pp.75-81
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• 1984

The effect of the saponin fraction extracted from Panax ginseng C.A. Meyer on the absorption of ${\alpha}$-tocopherol in rat has been investigated and realized that the saponin fraction stimulated not only the absorption of ${\alpha}$-tocopherol (1.5-2 times that of control) but also its transport and excretion. ${\alpha}$-tocopherol is known to be transported mainly in the form of ${\beta}$-lipoprotein but the present study showed that the ${\alpha}$-tocopherol was transported in the form of albumin bound or micellar structure as well.

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.505-508
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• 1990

The electrochemical reduction and electrogenerated chemiluminescence (ECL) of $Ru(bpy)_3^{2+}-S_2O_8^{2-}\;in\;CH_3CN-H_2O$ solution were studied in the presence of sodium dodecyl sulfate (SDS) as an anionic surfactant. SDS enhanced the ECL and the fluorescence intensities and lengthened the duration of ECL due to the solubilization of reactants and possibly to the stabilization of ECL intermediates in the SDS micellar environment.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.735-741
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• 2008

In our previous study, a surfactant-coated Candida rugosa lipase immobilized in microemulsion-based organogels was exploited for the synthesis of ethyl isovalerate. In the present study, we are focusing on the effective reuse of lipase immobilized in microemulsion-based organogels (MBGs) in terms of retainment of the catalytic activity. As water is one of the co-products in esterification reactions, the removal of water becomes a priority to allow the reaction to work in the forward direction and to prevent back hydrolysis. Taking this fact into consideration, the lipase-containing microemulsion-based organogels were given pretreatment and/or several intermittent treatments with dry reverse micellar solution of AOT in organic solvent during repeated cycles of ester synthesis. The pretreated MBGs with dry reverse micellar solution exhibited lower water content and higher initial rates of esterification in comparison with untreated freshly prepared MBGs. The esterification efficiency of untreated MBGs started decreasing after 5 cycles of reuse and was almost completely lost by the end of the $8^{th}$ cycle. In contrast, pretreated MBGs exhibited a gradual decrease in esterification efficiency after 5 cycles and retained about 80% of the initial activity at the end of the $8^{th}$ cycle. The intermittent treatment of MBGs after every 3 cycles resulted in enhanced reusability of immobilized lipase for up to 9 cycles without significant loss in esterification activity, after which it resulted in a slow decrease in activity with about 27% lower activity at the end of the $12^{th}$ cycle. Furthermore, the treatment conditions such as concentration of AOT in liquid dessicant and time of treatment were optimized with respect to our system. The granulated MBGs proved to be better in terms of initial esterification rates (1.2-fold) as compared with the pelleted MBGs.