고분자 이미다졸-금속 착제 LB막의 선책적 기체 투과성

김병주,이범종 인제대학교기초과학연구소 1999 자연과학 Vol.3 No.-

이미다졸-금속 이온구조를 갖는 고분자 Langmuir-Blodgett(LB)막을 다공성 막 필터 위에 제조하여 산소와 질소의 투과성을 이들의 캐스트 막과 비교하여 검토하였다. 양친매성 고분자 폴리(N-(2-(4-이미다졸일)에틸)말레이미드·alt-1-옥타데센)(IM-O)는 폴리(무수말레산-alt-1-옥타데센)과 히스타민의 반응으로 합성되었다. IM-O는 순수한 물 또는 금속 이온 (철(Ⅲ)과 코발트(Ⅱ)이온)하층액 위에서의 40 mN/m의 표면압력에서도 안정한 일분자막을 유지하였다. 이 일분자막은 30 mN/m의 표면 압력에서 FP-010 막 필터 위에 Y형태로 누적되었다. 이 다중막의 구조는 FT-IR을 통하여 확인하였다. LB막의 균일성과 안정성은 SEM 관찰을 통하여 간접적으로 평가하였고, 산소와 질소의 투과도는 감압법을 이용하여 측정하였다. 본 LB막들의 기체 선택성은 산소보다 질소가 약간 높게 나타났으며, 두 기체에 대하여 모두 고투과성을 나타냈다. 이들 고분자-금속 착체의 캐스트 막을 제조하여 기체 투과도를 측정한 결과 질소에 대한 선택성은 변함이 없었다. The permeability of oxygen and nitrogen was investigated from the polymeric LB films containing imidazole-metal ion complexes and compared with its corresponding cast films on porous membrane filters. The amphiphilic polymer, poly(N-(2-(4-imidazolyl)ethyl)-maleimide-alt-1-octadecene)(IM-O), was synthesized by reaction of poly(maleic anhydride-alt-1-octadecene)with histamine. Chloroform solutions of IM-O were spread on pure water and aqueous metal ions(iron(Ⅲ) and cobalt(Ⅱ)ions) and the monolayers showed high stability up to 40 mN/m against surface pressure. The monolyers of polyion-complexed polymers at the air-water interface can be transferred onto solid substrates such as a porous fluorocarbon membrane filter(FP-010) and a CaF2 plate. The Y-type deposition was found at a surface pressure of 30 mN/m. The molecular structures of LB films were investigated by means of FT-IR spectroscopy. The mechanical stability and uniformity of the LB films on FP-010 membranes were indirectly evidenced by SEM observation of the surface morphology of FP-010 membranes were indirectly evidenced by SEM observation of the surface morphology of FP-010 covered with the LB films. The permeability of oxygen and nitrogen was measured with the pressure method. The LB films showed more or less higher selectivity toward nitrogen, and high permeability was found to both the oxygen and nitrogen. The cast films of the corresponding polymer-metal complexes also showed preference to nitrogen in selectivity.

화상창상의 치유 및 반혼형성 과정에서 신경펩티드의 변화

장영철,범진식,이종욱,오석준 대한화상학회 2003 대한화상학회지 Vol.6 No.2

화상창상의 치유 및 반흔형성 과정에서 신경펩티드의 변화

장영철,범진식,이종욱,오석준 대한화상학회 2003 대한화상학회지 Vol.6 No.2

2-헵타데실-2-옥사졸린의 공기-물 계면에서의 일분자막 및 LB막 특성

황선경,이범종 인제대학교 기초과학 연구소 1999 자연과학 Vol.3 No.-

2-헵타데실-2-옥사졸린(C17-OXZ)양친매성 분자의 공기-물 계면에서의 개환 반응과 Langmuir-Blodgett(LB)막의 가교화에 대해 연구하였다. C17-OXZ는 스테아르산과 2-아미노에탄올의 탈수 및 고리화 반응에 의해 합성되었다. 일분자막의 특성은 표면압력-면적(π-A)등온선으로 확인하였다. 하층액이 산성일 때 또는 폴리알릴아민을 포함하고 있을 때 일분자막이 더욱 팽창하였다. 그러나, 알칼리 하층액에서는 순수인 경우에 비하여 π-A등온선상에 주목할 만한 변화가 관찰되지 않았다. 폴리아크릴산을 포함하는 경우에서는 더욱 팽창된 일분자막을 형성하였고 표면압력의 자발적인 증가가 발견되었다. 일분자막의 상변화는 Brewster 각 현미경(BAM)에 의하여 관찰되었다. 일분자막들은 플루오르화 칼슘기판에 누적되었고 FT-IR 분광법으로 분자구조를 결정하였다. 그 결과 옥사졸린의 개환 중합보다는 이미노 이중결합의 가수분해 반응이 우세함을 확인하였다. LB막의 안정성은 다공성 기판 위로의 누적형태를 주사 전자 현미경으로 관찰함으로써 간접적으로 평가하였다. 하층액에 폴리아크릴산을 포함하는 경우가 가장 안정된 LB막을 형성하였다. The network structures of monolayers are important for molecularly-thin films such as the LB film in order to improve the intrinsic fragility and to make their technological applications possible. In this study, we investigated the ring-opening reaction of 2-heptadecyl-2-ox-azoline(C17-OXZ) at the air-water interface and its formation of network LB films. The amphiphile C17-OXZ was synthesized via dehydration and cyclization of stearic acid with 2-am-inoethanol. Monolayer behaviors were studied at the air-water interface by measuring the surface pressure-area(π-A)isotherms. When the subphase became acidic or contained poly(allylamine), the monolayers showed more expanded phases. However, any noticeable change of the π-A isotherm was not observed in alkaline subphase compared with that of pure water subphase. When poly(acrylic acid)was dissolved in the subphase, the π-A isotherm revealed expanded monolayer and a spontaneous increase of surface presssure was found. Phase changes of the monolayers were observed by Brewster angle microscopy(BAM). The monolayers were transferred onto calcium fluoride substrates and the molecular structures were determined by the FT-IR spectroscopy. However, the competitive advantage was favored to hydrolytic reaction of imino double bond rather than the ring-opening polymerization expected from the imino nitrogn on oxazoline ring. The stability of the network film was indirectly evaluated by the SEM observation of the film morphology covered over the porous substrate. The most stable LB film was produced from the subphase containing poly(acrylic acid)

곁사슬형 Polyethylene Glycol을 가진 Adenosine Deaminase 결합체의 생화학적 특성

안치운,이범종,김동규 인제대학교 1996 仁濟論叢 Vol.12 No.2

Calf adenosine deaminase(ADA) was modified with pendant-type polyethylene glyco1(PEG) using cyanuric chloride as a coupler. Attachment of PEG to the enzyme alters the kinetic profile of the enzyme in that a decrease in the Km for adenosine. The Km value of the ADA and PEG-ADA10 were 30 μM, 25 μM against adenosine, respectively. But the PEG-ADA20 exhibited reasonable retention of catalytic activity with a increased Km, it was 50 μM against adenosine. Thermal inactivation at temperature above optima was essentially the same for the native and modified enzyme. PEG appears to have no effect on stabilizing to high temperature. This suggests that PEG attachment causes some destabilization of the adenosine deaminase structure. The electrophoretic mobility in polyacrylamide gels of PEG-ADA was severely reduced as compared to the native enzyme. Unmodified proteins show single band, whereas the modified enzyme forms a number of bands throughtout the gels. The decreased electrophoretic mobility of PEG-ADA may be due to a charge-shielding effect of the hydrophilic PEG shell surrounding the enzyme. In addition, the increased size of the adducts formed may serve to retard migration in the polyacrylamide gels. The present results show that the biochemical properties of adenosine deaminase were altered after chemical modification with PEG.

An Ultrathin Polyimide Insulation Layer by Using Dihexadecyl Phosphate as Monolayer Template

Burm-Jong Lee,Hee Sang Kim,Eun Mi Son,Hoon-Kyu Shin,Young-Soo Kwon 대한전기학회 2002 KIEE International Transactions on Electrophysics Vol.12C No.2

An Ultrathin Polymer Network through Polyion-Complex by Using Sodium Dioctadecyl Sulfate as Monolayer Template

Lee, Burm-Jong,Kim, Hee-Sang,Kim, Seong-Hoon,Son, Eun-Mi,Kim, Dong-Kyoo,Shin, Hoon-Kyu,Kwon, Young-Su Korean Chemical Society 2002 Bulletin of the Korean Chemical Society Vol.23 No.4

Two-dimensionally cross-linked ultrathin films of poly(maleic acid-alt-methyl vinyl ether) (MA-MVE) and poly(allylamine) (PAA) were produced by using sodium dioctadecyl sulfate (2C18S) as the monolayer template for Langmuir-Blodgett (LB) depositio n. The template molecules were subsequently removed by thermal treatment followed by extraction. The polyion-complexed monolayers of three components, i.e., template 2C18S, co-spread PAA, and subphase MA-MVE, were formed at the air-water interface. Their monolayer properties were studied by the surface pressure-area isotherm. The monolayers were transferred on solid substrates as Y type. The polyion-complexed LB films and the resulting network films were characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The cross-linking to form a polymer network was achieved by amide or imide formation through heat treatment under a vacuum. SEM observation of the film on a porous fluorocarbon membrane filter (pore diameter 0.1 ㎛) showed covering of the pores by four layers in the polyion complex state. Extraction by chloroform followed by heat treatment produced hole defects in the film.

Enantioselective Inhibition Effect on Esterolytic Activity of ${\beta}$-Cyclodextrin by Inclusion with N-Benzoxycarbonyl-L-histidine

Burm-Jong Lee,Iwhan Cho Korean Chemical Society 1990 Bulletin of the Korean Chemical Society Vol.11 No.2

Monolayer Stability of Amphiphilic Poly(itaconate-methacrylate)s According to the Copolymer Composition

Lee, Burm-Jong 인제대학교 1998 仁濟論叢 Vol.14 No.1

The stabilities of the monolayers and the Langmuir-Blodgett (LB) films of amphiphilic poly(itaconate-co-metacrylate)s were evaluated according to the copolymer composition. Monooctadecyl itaconate (C18ITA) was synthesized from reaction of itaconic anhydride with 1-octadecanol. C18ITA was copolymerized with poly(ethylene glycol) (400) monomethyl ether monomethacylate (ME9) through radical polymerization with various feed ratios, and the copolymers P1, P2, and P3 having 76, 59, and 28 mole % of ME9 component were obtained, respectively. The monolayer. and LB film stabilities were estimated by the surface pressure-area isotherm and scanning electron microscopy, the stability was the order of P3〉P2〉P1. The stability was enhanced by addition of poly(allylamine) into the subphase through the polyion-complexation between carboxyl and amino groups of different polymers. Keywords: monolayer, Langmuir-Blodgett film, stability, copolymer composition

Stereoselective Inhibition Effect on Esterolytic Activity of β-Cyclodextrin by Inclusion with Histidine Derivatives

Lee, Burm-Jong,Cho, Sung-Dae 인제대학교 1995 仁濟論叢 Vol.11 No.1

β-시클로덱스트린(β-CD)에 의한 에스테르 분해 반응에서 히스티딘 유도체와의 포접 착체 형성에 의해 입체선택적 저해 작용이 있음을 밝혔다. 광학 활성 기질로서 N-Carbobenzoxy-D-와 L-phenylalanine p-nitrophenyl esters(D-NBP 및 L-NBP) 그리고 N-carboethoxy-D-와 L-phenylalanine p-nitrophenyl esters(D-NEP 및 L-NEP)을 사용하였다. 히스티딘 유도체로는 N-Carbobenzoxy-L-histidine(Z-His-OH)과 그의 메틸 에스테르를 사용하였다. 2-His-OH의 존재하에서 β-CD에 의한 D-NBP의 가수분해 저해 작용이 가장 크게 나타났다. 완충 용액의 종류에 따라서도 위 반응에 대한 β-CD의 촉매 활동도 및 입체 선택성이 영향을 받았다. L-기질에 대한 촉매 활동도는 borax 및 bicarbonate 완충 용액이 tris 및 Phosphate 완충 용액보다 증가 하였으며, 입체 선택성은 bicarbonate 완충용액에서 가장 큰 값(kcat(L)/kcat(D)=4.25)을 보였다. Z-His OMe는 Z-His-OH에 비하여 β-CD와의 포접 착체 형성이 적고, 입체 선택적 저해 작용도 크지 않았다.