Polymer-directed Crystallization of Sibutramine using Cellulose Derivatives

( Ha Rim Bae ),( Hye Seung Lee ),( Min Kyung Lee ),( Jong Hwi Lee ) 한국약제학회 2011 Journal of Pharmaceutical Investigation Vol.41 No.1

Nonclassical pathway of crystallization has been utilized to modify the properties and morphologies of inorganic and organic/inorganic materials. In here, the polymer-directed crystallization method has been applied to the pharmaceutical active ingredient to assess the applicability for as a particle engineering tool. The polymer-directed crystallization was successful to modifying the crystal size, habit and morphology, but it was not effective to discover the novel polymorphs of Sibutramine (SB). SB was selected as a model drug and polyacrylic acid (PAA), polyethylene imine (PEI) and chitosan (CHI) were added as a crystallization pathway modifier. SB was crystallized via drowning crystallization using methanol or ethanol as a solvent and water as a non-solvent. The significant interactions between polymer and the drug were confirmed by measuring the solubility of the drug in presence of polymer during the crystallization. The crystal forms of SB are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and optical microscope (OM). The polymer-directed crystallization seems to be able to modify the crystal properties of pharmaceutical active ingredient, which is critical in determining the bioavailability, processability, and stability.

Surface modification of fluorine-doped tin oxide films using electrochemical etching for dye-sensitized solar cells

Bae, Ju-Won,Koo, Bon-Ryul,An, Ha-Rim,Ahn, Hyo-Jin Elsevier 2015 CERAMICS INTERNATIONAL Vol.41 No.10

<P><B>Abstract</B></P> <P>We modified the surface of fluorine-doped tin oxide (FTO) films using electrochemical etching in order to improve the photovoltiac performance of dye-sensitized solar cells (DSSCs). For the electrochemical etching, a mixture of HCl and zinc precursor was used as the electrolyte, which generated the H<SUP>+</SUP> needed for activating the SnO<SUB>2</SUB> etching reaction. This led to the formation of surface-modified FTO films that resulted in an increase in surface roughness and a high level of haze without changing the sheet resistance and optical transmittance of the FTO films. The open circuit voltage, fill factor, and short-circuit current density of the DSSCs assembled using the surface-modified FTO films were 0.73V, 60.53%, and 15.67mA/cm<SUP>2</SUP>, respectively. The surface-modified FTO films created using electrochemical etching showed an improved photoconversion efficiency (~6.95%) when compared to bare FTO films (~6.33%). This improvement in performance was caused by an improved ability to trap light by increasing haze, which resulted in an enhancement in the surface roughness of the FTO films.</P>

Ultrasonic Velocity and Absorption Measurements for Polyacrylamide and Water Solutions

Bae, Jong-Rim,Kim, Jeong-Koo,Yi, Meyung-Ha The Acoustical Society of Korea 2003 韓國音響學會誌 Vol.22 No.e4

Both ultrasonic velocity at 3 MHz and absorption coefficient for the frequency range of 0.2-2 MHz were measured in an aqueous solution of polyacrylamide for the concentration range of 0.5% to 2.5% by weight. Pulse echo overlap method was taken for measuring the ultrasonic velocity over the temperature range of 10-90℃ and the high-Q ultrasonic resonator method was used for the absorption coefficient at 30℃. The velocity exhibited a maximum value at approximately 70℃, 71℃, 72℃, 73℃ and 74℃ in 2.5%, 2.0%, 1.5%, 1.0%, and 0.5% solutions, respectively. The velocity increased with the concentration at a given temperature. The ultrasonic absorption (a/f²) at a given temperature increased linearly with the concentration for the concentration below 1.5%, but suddenly increased for the concentration above 1.5% concentration. The value of a/f² at 1MHz was entirely due to the classical Stoke's viscous effect. The ultrasonic relaxation in polyacrylamide aqueous solutions, which may be the result of structural fluctuations of polymer molecules such as the segmental motion of the polymer chains, was observed, and at 2.5%, the value of a/f² was found to suddenly increase as frequency decreased.

Fabrication of Elastic Silicone Thin Film of Self-adhesive, Transparent, and Free-standing Properties based on Hydrosilylation Reaction

Ha-Rim Kim,Seokyun Kang,Do-hyun Kim,Jin Young Bae 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

CAPD 중에 생긴 흉막삼출 2예

염하용(Ha Yong Yum),배상균(Sang Kyun Bae),임학(Hark Rim) 대한핵의학회 1994 핵의학 분자영상 Vol.28 No.1

Massive hydrothorax complicating continuous ambulatory peritoneal dialysis (CAPD) is relatively rare. A 67-year-old male and a 23-year-old female patients during CAPD presented massive pleural effusion, They have been performing peritoneal dialysis due to end-stage renal disease for 8 months and 2 weeks respectively. We injected 99mTc-labelled radiopharmaceutical (phytate and MAA, respec- tively) into peritoneal cavity witb the dialysate. The anterior, posterior and right lateral images were obtained. The studies reveal visible radioactivity in the right chest indicating the communication between the peritoneal and the pleural space. After sclerotherapy with tetracycline, the same studies reveal no radioactivity in the right chest suggesting successful therapy. We think nuclear imaging is a simple and noninvasive method for the differential diagnosis of pteural effusion in patients during CAPD and the evaluation of therapy.

Poly(acrylic acid)와 물의 혼합물에 대한 초음파 음속측정

이명하,배종림 大邱大學校 基礎科學硏究所 2000 基礎科學硏究 Vol.17 No.2

Ultrasonic velocity at 3 MHz and shear viscosity was measured in an aqueous solution of poly(acrylic acid) over the temperature range of 10~90℃, and the concentration range of 5 to 25% by weight. The velocity exhibits a maximum value at approximately 60, 62, 64, 68 and 70℃ in 25, 20, 15, 10, and 5% concentration solutions, respectively. The ultrasonic velocity increase with concentration at a given temperature. The shear viscosity decreased with temperature and increased with concentration.

Poly(sodium 4-styrenesulfonate)과 물의 혼합물에 대한 초음파 흡수측정

이명하,배종림 大邱大學校附設 基礎科學硏究所 2004 基礎科學硏究 Vol.21 No.1

Ultrasonic absorption coefficient in the frequency range of 0.2-2 MHz were measured in of poly(sodium 4-styrenesulfonate) aqueous solution for the concentration range of 5% to 25% by weight. The high-Q ultrasonic resonator method was used for the absorption coefficient at 20℃. The ultrasonic relaxation in poly(sodium 4-styrenesulfonate) aqueous solutions, which may be the result of structural fluctuations of polymer molecules such as the segmental motion of the polymer chains, was observed. Both the absorption and the shear viscosity increased with the poly(sodium 4-styrenesulfonate) concentration, but decreased with temperature.

방향족 무수물 기반의 에폭시 변성 아크릴레이트 바인더 합성 및 SiO₂ 레지스트 제조에 관한 연구

김하림(Ha-Rim Kim),김도현(Do-Hyun Kim),김영운(Young-Woon Kim),이운영(Woon-Young Lee),배진영(Jin-Young Bae) 한국고분자학회 2018 폴리머 Vol.42 No.4

본 연구에서는 유기 절연막에 적용 가능한 새로운 광경화 에폭시 변성 아크릴레이트의 합성 및 그 특성에 대해 살펴보았다. 우선 다양한 에폭시 변성 아크릴레이트를 합성하기 위하여 산 무수물과 하이드록시 아크릴 단량체의 조합에 의해 diesteric acid(DA) 유도체를 반응시켰다. 합성된 diesteric acid(DA)에 에폭시 화합물인 글리시딜 메타아크릴레이트(glycidyl methacrylate)를 반응시켜 광경화 타입의 에폭시 변성 아크릴레이트를 합성하였다. 그리고 실리카 분산액인 NANOBYK-3650과의 호환성을 살펴보았다. 사용한 단량체의 구조에 기인하여 실리카와 최적의 바인더를 선정하고 이를 고투과율·저유전 실리카 레지스트에 적용시키고자 배합을 하여 유기 절연막을 제조하였다. 실리카 함량에 따른 투과율, 패턴성, 열 안정성 그리고 전기적 특성(유전 상수)을 확인하였다. In this study noble UV-curable epoxy modified acrylates binder was designed and synthesized to apply an organic insulating film. Firstly, diesteric acid (DA) derivatives were prepared from anhydrides and hydroxy acrylates to synthesize epoxy modified acrylates. UV-curable epoxy modified acrylates were prepared from synthesized diesteric acid (DA) and epoxy chemicals, glycidyl methacrylate (GMA). The miscibility with silica millbase ‘NANOBYK-3650’ was investigated. Appropriate binder with silica was chosen by considering the monomer chemical structure. To obtain an organic insulating film with high transmittance and low k silica resist, optimum composition of UV-curable epoxy modified acrylates was also formulated. Transmittance, patternability, and electrical properties (dielectric constant) was measured.

Development of engineered Leuconostoc citreum capable of degrading uric acid

Ye-Rim Lee,Ha-Neul Bae,Seung-Oh Seo 한국식품영양과학회 2022 한국식품영양과학회 학술대회발표집 Vol.2022 No.10

Antitumor effects of genetically engineered stem cells expressing yeast cytosine deaminase in lung cancer brain metastases via their tumor-tropic properties.

Yi, Bo-Rim,Kim, Seung U,Kim, Yun-Bae,Lee, Hong Jun,Cho, Myung-Haing,Choi, Kyung-Chul National Hellenic Research Foundation 2012 Oncology reports Vol.27 No.6

<P>Although mortality related with primary tumors is approximately 10%, metastasis leads to 90% of cancer-associated death. The majority of brain metastases result from lung cancer, but the metastatic mechanism remains unclear. In general, chemotherapy for treating brain diseases is disrupted by the brain blood barrier (BBB). As an approach to improve treatment of lung cancer metastasis to the brain, we employed genetically engineered stem cells (GESTECs), consisting of neural stem cells (NSCs) expressing a suicide gene. Cytosine deaminase (CD), one of the suicide genes, originating from bacterial (bCD) or yeast (yCD), which can convert the non-toxic prodrug, 5-fluorocytosine (5-FC), into 5-fluorouracil (5-FU), can inhibit cancer cell growth. We examined the therapeutic efficacy and migratory properties of GESTECs expressing yCD, designated as HB1.F3.yCD, in a xenograft mouse model of lung cancer metastasis to the brain. In this model, A549 lung cancer cells were implanted in the right hemisphere of the mouse brain, while CM-DiI pre-stained HB1.F3.yCD cells were implanted in the contralateral brain. Two days after the injection of stem cells, 5-FC was administered via intraperitoneal injection. The tumor-tropic effect of HB1.F3.yCD was evident by fluorescent analysis, in which red-colored stem cells migrated to the lung tumor mass of the contralateral brain. By histological analysis of extracted brain, the therapeutic efficacy of HB1.F3.yCD in the presence of 5-FC was confirmed by the reduction in density and aggressive tendency of lung cancer cells following treatment with 5-FC, compared to a negative control or HB1.F3.yCD injection without 5-FC. Taken together, these results indicate that HB1.F3.yCD expressing a suicide gene may be a new therapeutic strategy for lung cancer metastases to the brain in the presence of a prodrug.</P>