• 분석과학
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• 제8권4호
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• pp.465-468
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• 1995

Matrix assisted laser desorption ionization in mass spectrometry is a fast and accurate method to determine the molecular weight of natural and synthetic polymers. Unknown peptides such as elastase inhibitor and $\small{D}$-hydantoinase were analyzed using sinapinic acid as matrix and their molecular weights were compared with the results from protein sequencer and gel filtration chomatography, respectively. Synthetic polymers such as polyethyleneglycol, polypropyleneglycol, polydimethylsiloxane, and polystyrene were analyzed using matrices such as 2,5-dihydroxybenzoic acid, 4-hdroxyazobenzenecarboxylic acid, and 2-nitrophenyl octyl ether. Average molecular weights of polystyrene were compared with molecular weights by gel permeation chromatography.

• Journal of Pharmaceutical Investigation
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• 제24권3호
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• pp.167-176
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• 1994

The microcapsules of amoxicillin using stearyl alcohol and polyethyleneglycol 8000 (PEG 8000) were prepared by a emulsion melted-cooled process in water phase. The size distribution, dissolution test, observation with SEM and in vivo test were investigated. The microcapsules obtained were spherical, uniform and free flowing particles. The release of drug from microcapsule was increased in proportional to the content of PEG 8000. As the PEG 8000 content increased, the particle size of microcapsule was decreased. Sanning electron micrograph study revealed that microcapsules had comparatively rough surfaces as drug content was increased. The $AUC_{0-12}$ after administration of amoxicillin microcapsules was more increased 40% as compared with the AUC after administration of amoxicillin powder in rabbits.

• Macromolecular Research
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• 제11권4호
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• pp.291-295
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• 2003

Dextran as a candidate material for colon-specific drug delivery has been studied. Crosslinked dextran hydrogels were prepared by mixing dextran, $MgCl_2$, glutaraldehyde (GA) and polyethyleneglycol (PEG 400) in water. The dextran hydrogels were characterized by measuring equilibrium swelling ratios and mechanical strengths. Response surface methodology (Central Composite Design) was used to evaluate the swelling behaviors and mechanical strengths as functions of concentrations of $MgCl_2$, GA, and PEG 400, which was found to be useful for the evaluation. It showed that the swelling behavior and mechanical strengths were influenced significantly by PEG 400 and $MgCl_2$ concentrations.

• 동위원소회보
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• 제21권4호
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• pp.46-54
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• 2006

Biocompatible and biodegradable hydrogels based on carboxymethyl cellulose(CMC) and polyethyleneglycol(PEG) were prepared far physical barriers for preventing surgical adhesions. These interpolymeric hydrogels were synthesized by a gamma irradiation crosslinking technique. The 1Scmxl.Scm of cecal serosa and adjacent abdominal wail were abraded with bane burr until tbe serosal surface was disrupted and hemorrhagic but not perforated. and the serosa of tbe cecum was sutured to the abdominal wall in 5mm apart from the injured sire. The denuded cecum was covered with either CMC/PEG hydrogels or solution from CMC/PEG hydrogel. Control rat serosa was not covered. Two weeks later. the rats were sacrificed and adhesion was scored on a 0-5 scale. No treatment showed the significantly higher incidence of adhesions than either CMC/BEC hydrogels or solution from CMC/PEG hydrogel. In conclusion, these studies demonstrate that CMC/BEG hydrogels have a function of prevention of intra abdominal adhesion in a rat model.

• 대한화학회지
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• 제47권5호
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• pp.479-486
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• 2003

본 연구에서는 나노입자의 제조 방법인 용매 확산 방법 (emulsification diffusion method)을 이용하여 poly (DL-lactide-co-glycolide) (PLGA) 나노입자를 제조하고 지용성 vitamin A (Retinol)와 Vitamin E acetate를 담지하였다. 고분자 용액은 물에 잘 혼합되는 유기 용매인 에탄올과 아세톤의 이종 혼합 용매를 사용하여 제조하였고 유화제는 생체적합성이 우수한 polyethyleneglycol-polypropyleneglycol diblock copolymer를 사용하였다. 고분자의 농도, 유화제의 농도, 물/오일상의 비, 고분자/약물의 비 등의 인자들이 나노입자의 형성과 약물의 담지 효율에 미치는 영향을 조사하였다. 활성 성분이 로딩된 나노입자를 제조한 후, 입자의 크기와 분포도는 광산란 입도 분석기를 이용하여 측정하였고 담지 효율은 UV-visible spectroscopy를 이용하여 평가하였다. 제조된 나노입자는 50-200 nm의 크기와 단분산 형태의 크기분포를 보였으며 담지 효율은 50-60%까지 얻을 수 있었다. 또한, 유기상과 수용액상에서 이종 혼합 용매와 고분자의 농도에 대한 적당한 조건을 조절함으로써 PLGA 나노입자의 높은 수율과 우수한 물리적 특성을 얻을 수 있었다.

• 한국안광학회지
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• 제17권1호
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• pp.1-10
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• 2012

목적: 본 연구는 cellulose acetate(CA)의 용융특성을 증가시키기 위해 polyethyleneglycol(PEG)를 도입함으로써 기존에 사용되는 환경유해성 가소제의 사용 없이 열가공성이 향상 된 CA/PEG 조성물을 제조하는데 목적이 있다. 방법: CA의 최적 가소화 조건을 확립하기 위해 PEG 분자량, 농도, 및 혼입온도를 제어하여 CA/PEG 조성물의 가소화 성능을 확인하였으며, CA와 PEG간의 혼화성을 확인하기 위해 제조된 조성물의 열분석 및 표면분석을 실시하였다. 또한 기존 상용 CA 레진과의 가소제 용출특성, 기계적 물성 및 광학적 특성들의 비교분석을 통해 가소제에 의한 물성차이를 검토하였다. 결과: PEG의 도입을 통해 기존 상용 CA 레진과 유사한 가소화 성능을 확인하였으며, 최적의 가소화 조건은 PEG분자량 400, PEG 함량 30~40 phr, 가소화온도 $175{\sim}180^{\circ}C$에서 우수한 용융특성을 나타냄을 확인 하였다. 또한 기존의 CA 안경테 소재와 비교 시 우수한 광택특성 및 안정성을 확인 하였으며, 동등수준 이상의 기계적 물성을 보임을 확인 하였다. 결론: CA/PEG 조성물은 환경 친화적 안경테 소재로써 기존 프탈레이트계 가소제를 사용한 CA 안경테 소재를 대체할 수 있을 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.651-656
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• 2012

Cationic immunoliposomes were prepared by conjugation of Fab' fragments of the recombinant humanized monoclonal antibody (HuCC49) against tumor-associated glycoprotein (TAG)-72 to sterically unilamella liposomes. The cationic immunoliposomes are composed of cationic lipid (O,O'-dimyristyl-N-lysyl aspartate, DMKD), cholesterol, and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[maleimide(polyethyleneglycol)$_{2000}$] (DPPE-PEG-maleimide) with a molar ratio of 0.5:0.47:0.03. Plasmid DNA was effectively condensed by addition of transferrin (Tf) during the formation of anti-TAG-72 PEG-immunolipoplexes (PILPs). These anti-TAG-72 PILPs were able to adhere to the surface of TAG-72-overexepressing LS174T human colon cancer cells more effectively than conventional liposomes, thereby facilitating gene delivery in vitro. Furthermore, intravenous administration of the anti-TAG-72 PILPs into the tumor-carrying mice exhibited efficient localization of the reporter gene in the tumor tissues.

• 한국결정성장학회지
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• 제9권6호
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• pp.590-596
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• 1999

염화물욕 아연도금에서 순환셀 도금장치에 3전극계를 부착하여 첨가제 효과를 조사하였다. 도금액에 폴리에틸렌글리콜(이하 PEG)의 첨가는 도금 과전압을 증가시키고 수소발생을 억제하는데 이것은 첨가제에 의하여 아연 이온의 이동을 억제하거나 음극에 첨가제 흡착에 의한 것으로 생각된다. 그러나 PEG는 사용되는 도금액의 물성(전도도, 점도, 비중)에는 영향을 미치지 않는 것으로 나타났다. 도금층에 미치는 영향은 표면 조도가 개선되고, 광택도가 감소된다. 이러한 영향은 PEG 분자수가 클수록 증가되나 분자수가 다른 PEG의 혼합첨가제에서는 광택도 감소가 줄어든다. 이러한 것은 도금층 결정면의 방향성, 입자의 크기 및 형태가 PEG 분자 수에 따라 다르게 나타나는 것에 기인하는 것으로 판단된다.

• Plant Biotechnology Reports
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• 제2권3호
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• pp.179-189
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• 2008

We established an efficient plant regeneration system for Catharanthus roseus L. (G.) Don through somatic embryogenesis. Embryogenic callus was induced from hypocotyl of seed germinated in vitro. Somatic embryogenesis in Catharanthus has been categorized into three distinct stages: (1) initiation and proliferation of embryo; (2) maturation, and; (3) germination or plantlet conversion. Beside plant growth regulators, various stages of embryogenesis were screened for their response to a wide variety of factors (pH, gelrite, light, sugar alcohols, polyethyleneglycol and amino acids), which affect embryogenesis. All of the tested factors had a small to marked influence on embryogeny and eventual conversion to plantlets. The plantlets were acclimatized successfully in a greenhouse. To our knowledge, this is the first report describing a detailed study of various cultural factors which regulate embryogenesis in C. roseus. The results discussed in this paper may be used in mass propagation to produce medicinal raw material, and the embryo precursor cells could be used in genetic modification programmes that aim to improve the alkaloid yield as well.

• Journal of Pharmaceutical Investigation
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• 제31권3호
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• pp.173-180
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• 2001

The physicochemical characteristics such as glass transition temperature (Tg), surface energy, swelling and FT-IR of [P(AA-co-PEGMM)], a copolymer of acrylic acid (AA) and polyethyleneglycol monoethylether mono methacrylate (PEGMM), were evaluated. The Tg of [P(AA-co-PEGMM)] decreased with increasing PEGMM content. [P(AA-co-PEGMM)] with 18 mole% PEGMM had the Tg of about $40^{\circ}C$, the similar physiological temperature of human. Moreover, [P(AA-co-PEGMM)] with lower PEGMM content had higher hydration and expected lower mucoadhesive strengths. To predict the mucoadhesiveness of [P(AA-co-PEGMM)] films, the contact angle of films were measured. With the increasing content of PEGMM of films, the contact angle was increased and the higher mucoadhesive forces was expected. ATR-FTIR studies revealed that the addition of the PEG moiety in AA increased the potential of hydrogen bonding for [P(AA-co-PEGMM)] as compared to cross linking polyacrylic acid (cr-PAA) because the oxygen in the repeat unit of PEG contributed in the formation of hydrogen bonding in the presence of mucin solution.