• Macromolecular Research
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• 제12권3호
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• pp.263-268
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• 2004

We have synthesized a water-soluble polyimide precursor, poly(amic acid) amine salt (PAD), from pyromellitic dianhydride (PMDA), 4,4'-oxydianiline, and N,N -dimethylethanolamine (DMEA) and have investigated in detail its properties with respect to the degree of salt formation (D$\_$sf/). The maximum value of D$\_$sf/ we obtained upon precipitation of the precursor solution into acetone was 79%. We synthesized a PAD having a D$\_$sf/ of 100% (PAD100) by the solid state drying of an organic solution. The precursors showed different solubility depending on the D$\_$sf/ to make up to 4 wt% solutions in water containing a small amount of DMEA. PAD100 is completely soluble in pure water. We investigated the imidization behavior of PAD in aqueous solution using various spectroscopic methods, which revealed that PAD 100 has faster imidization kinetics relative to that of the poly(amic acid)-type precursors. The resulting polyimide films prepared from an aqueous precursor solution possess almost similar physical and thermal properties as those prepared from N-methyl-2-pyrrolidone(NMP) solution. Therefore, we have demonstrated that PAD can be used as a water-based precursor of polyimide; this procedure avoids the use of toxic organic solvents, such as NMP.

• 한국식품저장유통학회지
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• 제7권2호
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• pp.171-176
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• 2000

Drink and tea-bag were processed with safflower seed powder. Drinks were processed with 90$^{\circ}$C hot water extraction. Yield, soluble solid, pH and centrifugation residue of drinks were ranged in 79.2~89.3%, 0.6~0.99%, 5.98~6.40 and 1.00~1.18, respectively. Sensory score of overall acceptance in drinks were highest at that of enzyme treated drink. Tea-bag was processed with roasted safflower seed powder, alone(1.2g) and the mixtured tea-bags were consisted of persimmon leaves, pine needle and angelica gigas powder in same amount, respectively. Teas were prepared with extraction at 80$^{\circ}$C water for 2 min. Soluble solid and sensory evaluation score of teas were the highest when the tea was processed with safflower seed alone.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.294.1-294.1
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• 2001

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1421-1430
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• 2009

With an aim to evaluate dye decolorization by white rot fungus on natural living conditions, reproducing by solid-state fermentation, the process of triphenylmethane dyes decolorization using the white rot fungus P. ostreatus BP, cultivated on rice straw solid-state medium, has been demonstrated. Three typical dyes, including malachite green, bromophenol blue, and crystal violet, were almost completely decolorized by the fungus after 9 days of incubation. During the process of dye decolorization, the activities of enzyme secreted by the fungus, and the contents of soluble components, such as phenolic compounds, protein, and sugar, changed regularly. The fungus could produce ligninolytic, cellulolytic, and hemicellulolytic enzymes and laccase was the most dominant enzyme in solid-state medium. Laccase, laccase isoenzyme, and the laccase mediator could explain the decolorization of malachite green, bromophenol blue, and crystal violet by the fungus in solid-state medium, respectively. It is worth noting that the presence of the water-soluble phenolic compounds could stimulate the growth of fungus, enhance the production of laccase, and accelerate dye decolorization.

• Journal of Pharmaceutical Investigation
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• 제38권2호
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• pp.111-117
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• 2008

To overcome the solubility of poorly water-soluble drug, the formation of solid dispersion using a spray-dryer with polymeric material, that can potentially enhance the dissolution rate extend of drug absorption was considered in this study. $Eudragit^{(R)}$ E100 as carrier for solid dispersion is acrylate copolymer that soluble in acidic buffer solutions (below pH 5.0). It was used to increase dissolution of atorvastatin calcium as a water-insoluble drug in acidic environments. In this study, a spray-dryer was used to prepare solid dispersion of atorvastatin calcium and $Eudragit^{(R)}$ E100 for purpose of improving the solubility of drug. Atorvastatin calcium and $Eudragit^{(R)}$ E100 were dissolved in ethanol and spray-dryed. DSC and XRD were used to analyze the crystallinity of the sample. It was found that atorvastatin calcium is amorphous in the $Eudragit^{(R)}$ E100 solid dispersion. FT-IR was used to analyze the salt formation by interaction between atorvastatin calcium and $Eudragit^{(R)}$ E100. Comparative dissolution study exhibited better dissolution characteristics than the commercial drug ($Lipitor^{(R)}$) as control. The dissolution rate of atorvastatin calcium was markedly increased in solid dispersion system in simulated gastric juice (pH 1.2). This study proposed that this solid dispersion system improved the bioavailability of poorly water-soluble atorvastatin calcium.

• 대한화학회지
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• 제36권6호
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• pp.933-940
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• 1992

Calix[6]arene을 포름알데히드와 이차아민과 반응시키면 물에 녹는 칼릭세린 염기가 얻어진다. 이를 메틸요오드로 처리하여 암모늄 염을 만들고 다양한 친핵성 물질과 반응시키면 칼릭세린의 파라위치에 작용기가 포함된 calix[6]arene이 얻어진다. Calix[6]arene도 포름알데히드와 이차의 아릴아민과 반응시켜 물에 녹는 칼릭세린 아민을 만들었다. 이렇게 합성된 칼릭세린중 물에 녹는 아민과 산기가 포함된 calix[6]arene과 calix[8]arene을 운반체로 이용하여 중성의 방향족 물질들을 통과시키는 연구를 U 형태의 유리관을 이용하여 수행하였다. 방향족 기질들로는 나프탈렌, 안트라센, 파이렌, 풀우란텐 등의 고체물질을 사용하였다.

• Journal of Pharmaceutical Investigation
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• 제20권1호
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• pp.13-18
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• 1990

Hydrocortisone (HC) sustained-release suppositories were prepared by using a solid matrix of methacrylic acid-methacrylic acid methyl ester copolymer $(Eudragit\;L_{100}^{R}:\;EL)$ as a poorly water soluble carrier and polyethylene glycole 1540 (PEG) as an water soluble carrier. HC release rate was controlled by complexation with ${\beta}-cyclodextrin$ $({\beta}-CyD)$ which was confirmed by X-ray diffractometry, IR-spectroscopy and differential scanning calorimetry. Release rate of HC from the EL-PEG matrix suppositories decreased with increase of EL contents. The release rale from $HC-{\beta}-CyD$ complex decreased in the following order: $HC-{\beta}-CyD/PEG$ > HC/PEG > $HC-{\beta}-CyD/EL_{10%}-PEG$ > $HC/EL_{10%}-PEG$ > $HC-{\beta}-CyD/EL_{15%}-PEG$ > $HC/EL_{15%}-PEG$ > $HC-{\beta}-CyD/EL_{20%}-PEG$ > $HC/EL_{20%}-PEG$. The crystallinity of HC in polymer matrix was identified using X-ray diffractometer and the surface of matrix suppositories after release test was examined by scanning electron microscopy. The sustained release of HC from these matrix suppositories was attributed to the network structure of EL.

• Journal of Pharmaceutical Investigation
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• 제6권3호
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• pp.58-69
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• 1976

It is well established that dissolution is freruently the rate limiting step in the gastrointestinal absorpton of a drug from a solid dosage from. The relationship between the dissolution rate and absorption is particularly distinct when considering drugs of low solubility. Consequently, numerous attempts have been made to modify the dissolution characteristics of poorly water soluble drugs. Since dissolution rate is directly proportional to surface area, one may increase the rate by decreasing the particle size of the drug. Levy has considered a number of methods by which a drug may be presented to the GI fludids in finely divided from. The direct method is the utilization of microcrystalline or micronized particles. A second method involves the administration of solutions from which, upon dilution with gastric fluids, the dissolved drug will precipitate in the form of very fine particles. A more unique way of obtaining microcrystalline dispersions of a drug has been ercently suggested by Sekiguchi et al. They have first proposed the formation of a eutectic mixture of a poorly water soruble drug with a physiologically inert, easily soluble carrier. When such systems are exposed to water or GI fluids, the soluble carrier will dissolve rapidly and the finely dispersed drug particles will then be released. It has been suggested by Shefter and Higuchi that the formation of crystalline solvate could be a powerful tool in affecting rapid disslution of highly insoluble substances. Goldberg et al. have noted that the formation of solid solution could reduce the particle size to a minimum and increase the dissolution rate as well as the solubility of the durgs. It has also been shown that the rates of solution of drugs were appreciably increased by coprectipitating the drug with soluble polymers. The increase was found to be sensitive to the method of preparation, the molecular weight of polymer and the particular ratio of drugs to polymer. Although several investigations have demontrated that the solubility and/or dissolution rates of drugs can be increased in this manner, little information is available in the literature related to the in vivo absorption pattern of drugs orally administered as PVP coprecipitates. Recently, however, it was demonstrated that both the rate and extent of absorption of the insoluble drug could be markedly enhanced when orally administered to rats in the form of a coprecipitate with PVP. The purpose of the present investigation was to ascertain the general appility of soluble polymer coprectation technique as a method for enhancing the in vitro dissolution rate of hydrophobic indomethacin. To accomplish this aim, the dissolution characteristics of pure indomethacin, indomethcin-polymer physical mixtures and indomethacin-polymer coprecipitates were quantitatively studied by comparing their relative dissolution rates. The solubility and dissolution behavior of these systems were also examined.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.54-62
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• 2013

Fine suspended solids and soluble heavy metals generated from mine drainage could destroy environment as the aesthetic landscapes, and depreciate water quality. Therefore, this research is focused on process development applied the actual field for controlling fine suspended solids and heavy metals, and so that bench-scale tests were performed for field application based on advanced researches. The field of mine drainage in this research was in H mine located Taebaek-si, Gangwon-do. The inclination plates were mounted 2 kinds of arrangement (octagon and radial types) in circle type settling basin. The inclination plates could be helped to settle of suspended solids; decreased 34% of suspended solids and 50% of turbidity in effluent. Radial type of inclination plates showed the results that is more efficient to settle of suspended solids (average to 3.45 mg/L) compared to octagon type. In the experiments to decrease retention time of mine drainage in settling basin from 6 hrs to 1.5 hrs, suspended solid concentration was exceeded to 30 mg/L as the standard for suspended solid at 10 days after the operation under tha retention time of 3hrs and 1.5hrs. In the tests for filtration, granular activated carbons were indicated the better effective to filtering and absorption of fine suspended solid and soluble heavy metals than anthracite.

• 한국식품과학회지
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• 제30권3호
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• pp.535-541
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• 1998

수용성 추출물을 이용한 관능검사 결과를 분석한 결과 고추가루 관련 식품에서 각각의 식품을 결정짓는데 가장 영향을 미치는 것은 적색도, 매운맛, 단맛, 새콤한 맛, 감칠맛 등의 조화로서 이들이 고추의 맛과 색을 좌우하는 것으로 나타났다. 각 추출 온도와 시간에서 연상되는 음식은 고추장과 찌개, 김치의 맛으로 구분될 수 있으며 추출조건에 따른 추출액과 이를 이용한 관능검사의 관계를 주성분 분석한 결과 총인자의 51%를 주성분 1과 주성분 2로 설명 가능하였다. 추출온도 $40^{\circ}C$에서 추출했을 때는 감칠맛, 새콤한 맛, 단맛이 높은 상관관계를 나타냈으며 $4^{\circ}C$의 경우는 색소성분과 주로 관련이 높았고 $60^{\circ}C$로 추출한 용액의 경우는 떫은맛, alcoholic, 매운맛과 높은 상관관계를 보여주고 있다. 따라서 낮은 온도에서는 주로 색소성분이 그리고 온도가 점차 올라 갈수록 맛성분들이 점차 용출되어 각각의 특성에 영향을 미치는 것으로 나타났다.