• 제목/요약/키워드: Dendrimer

검색결과 152건 처리시간 0.029초

아조벤젠이 기능화된 덴드리머 유기단분자막의 광학적 성질과 특성 (Characteristics and Optical Properties of the Azobenzene Functionlized Dendrimer in Organic Thin Monolayers)

  • 손정호;윤회찬;김정명;김병상;신훈규;장정수;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.182-185
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    • 2001
  • The functionlized dendrimer containing 48 azobenzene was synthesized. Many isolated featureless domains were explicitly observed even at the air-water interface. Also, these monolayers were representatively observed, showing the change of surface pressure with irradiation time and wavelength. In AFM images. the larger domains irregularly shaped structures on the top while the smaller ones were free from such defects. In the optical absorption spectra of the LB films by UV irradiation and heat treatment, only photoisomerization of the G4-48Az monolayers was observed, a decrease of absorbance peak without change of the spectral shape. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.

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쌀겨회재에서 추출된 실리카를 이용한 메조포러스실리카 SBA-15의 계단식 Dendrimer의 합성 (Step-wise Growth of Dendrimer over Mesoporous SBA-15 Synthesized Using Ricehusk Ash as Silica Source)

  • 이지윤;이화영;말간단 바기야락스미;장현태
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2009년도 춘계학술발표논문집
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    • pp.91-94
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    • 2009
  • 쌀겨회재에서 추출한 실리카원을 이용하여 메조포러스실리카 SBA-15를 합성하였으며, 이산화탄소에 대한 높은 선택성을 나타내는 아민기를 우수한 구조성을 지닌 메조포러스실리카에 그라프팅하였다. 아민기가 그라프팅된 메조포러스실리카에 높은 흡착능을 도출하기 위해서 dendrimer/SBA-15를 반응조건에 따라 합성하였다. 이와 같이 합성된 고체흡수제는 X-선 회절분석, 질소 흡,탈착 곡선, 분광분석 (FT-IR)등의 특성 분석을 수행하였고, 열중량반응기 및 충전층 반응기에서 이산화탄소 흡수실험을 수행하였다.

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Synthesis of Dendrimer Containing Dialkylated-fluorene Unit as a Core Chromophore via Click Chemistry

  • Han, Seung-Choul;Jin, Sung-Ho;Lee, Jae-Wook
    • Bulletin of the Korean Chemical Society
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    • 제33권1호
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    • pp.137-142
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    • 2012
  • The convergent synthetic strategy for the emissive dendrimers having the chromophore at core via the coppercatalyzed 1,3-dipolar cycloaddition reaction between alkyne and azide was described. 2,7-Diazido-9,9-dioctyl-9H-fluorene, designed to serve as the core in dendrimer, was stitched with the alkyne-functionalized Frechettype and PAMAM dendrons by the click chemistry leading to the formation of the corresponding fluorescent dendrimers in high yields. The preliminary photoluminescence studies indicated that 2,7-diazido-9,9-dioctyl-9H-fluorene showed no fluorescence due to the quenching effect from the electron-rich ${\alpha}$-nitrogen of the azido group but the dendrimers fluoresced due to the elimination of the quenching through the formation of the triazole ring.

기능성 LB단분자막의 물성에 관한 연구 (A Study on the Physical Properties of Functional LB Monolayers)

  • 송진원;신훈규;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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    • pp.404-407
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    • 2003
  • Monolayers of lipids on a water surface have attracted much interest as models of biological membranes, but also as precursors of multilayer systems promising many technical applications. Until now, many methodologies have been developed in order to gain a better understand. Photoisomerization in monolayers of a novel azobenzene compound, azobenzene dendrimer, was investigated for the first time by means of the absorption spectrum and Maxwell displacement current (MDC) technique. Dendrimers are well-defined macromolecules exhibiting a tree-like structure, first derived by the cascade molecule approach. According to the absorption spectrum, trans-to-cis conversion ratio was estimated to the third generation of azobenzene dendrimer deposited onto a glass substrate. Temperature-dependent induced charge with trans-cis isomerization was also measured by means of MDC technique.

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Patterning Biological Molecules onto Poly(amidoamine) Dendrimer on Gold and Glass

  • Hong, Mi-Young;Lee, Do-Hoon;Yoon, Hyun C.;Kim, Hak-Sung
    • Bulletin of the Korean Chemical Society
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    • 제24권8호
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    • pp.1197-1202
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    • 2003
  • Patterning of biological molecules was attempted on both gold and glass using fourth generation (G4) poly(amidoamine) (PAMAM) dendrimer as an interfacing layer between solid surfaces and biomolecules. As for the patterning of avidin and anti-biotin antibody on gold, PAMAM dendrimers representing amine functionalities were firstly printed onto the 11-mercaptoundecanoic acid SAM by microcontact printing, followed by biotinylation, and reacted with fluorescence-labeled avidin or anti-biotin antibody. Fluorescence microscopic analysis revealed that the patterns of avidin and anti-biotin antibody were well constructed with the resolution of < 2 ㎛. The PAMAM dendrimers were also printed onto aldehyde-activated slide glass and reacted directly with anti-BSA antibodies, which had been oxidized with sodium periodate. As a result, distinct patterns of the anti-BSA antibodies were also obtained with a comparable edge resolution to that of avidin patterns on gold. These results clearly show that PAMAM dendrimers can be adopted as an interfacing layer for the patterning of biological molecules on solid surfaces with micrometer resolution.

나노구조 기능성 유기박막의 변위특성 (Displacement Properties of Nano Structure Functional Organic Thin Films)

  • 송진원;이경섭;임중열
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2004년도 추계 종합학술대회 논문집
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    • pp.554-557
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    • 2004
  • 수면 위의 지질 단분자는 박막 모델로서 많은 관심을 끌고 있으며, 많은 기술적인 응용법에 의해 다층의 박막 시스템을 연구하고 있다. 아조벤젠 혼합물인 아조벤젠 덴드리머의 단분자막에서 광이성화는 흡수스펙트럼과 멕스웰 변위전류법(MDC)에 의해 관찰할 수 있다. 덴드리머는 나뭇가지 모양을 닮은 고분자이며, 흡수스펙트럼에 의해 trans-to-cis 변환을 평가할 수 있다. 본 연구에서는 덴드리머의 광이성화특성에 관하여 연구하였다.

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Synthesis and Characterization of a Receptor-Targeting Contrast Agent

  • Yang, Taegyun;Park, Ji-Hyung;Lee, Seung-Cheol;Kim, Cheol-Su;Cho, Jee-Hyun;Lee, Chul-Hyun;Cheong, Chae-Joon
    • 한국자기공명학회논문지
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    • 제7권1호
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    • pp.46-54
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    • 2003
  • We synthesized a contrast agent for MRI that is capable of binding to the ABP-1 receptor and enhancing the contrast of the targeted cells. We used a lysine dendrimer (G=3)DTPA[Gd] as the contrast agent and synthesized a biotinylated polyclonal antibody for ABP-1 as the first antibody. Lysine dendrimers were prepared using the solid phase peptide synthesis method.$^3$ Amino-terminated lysine dendrimers were then coupled to DTPA using the anhydride method. Gd was complexed with the DTPA-lysine dendrimer in an acidic solution of 3 eq GdCl$_3$ to one of DTPA. The lysine dendrimer-DTPA[Gd] and avidin were conjugated in MES solution, pH 6.0, using EDC as the coupling reagent. The biotin-avidin system was used to link the polyclonal antibody and contrast agent. K562 cells were used for imaging.

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나노구조 단분자막의 전기적 특성 (Electrical Characteristics of Nano-Structural Monolayer)

  • 최용성;조장훈;송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.166-167
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    • 2006
  • Dendrimers represent a new class of synthetic macromolecules characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L-films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for Impression.

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Construction and Patterning of the biospecific affinity surfaces on gold using dendrimer

  • 홍미영;윤현철;김학성
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.703-706
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    • 2000
  • We constructed a biospecific affinity surface using hyper-branched dendrimers on gold for biospecific recognition, and characterized the resulting surfaces by using confocal fluorescence microscopy. The dendrimer monolayer was firstly constructed on the mercaptoundecanoic acid SAM/Au with pentafluorophenyl ester activation and further functionalized with sulfo-NHS-biotin, an activated ester of biotin. To confirm the formation of biospecific affinity surface, FITC(fluorescein isothiocyanate)-labeled avidin was loaded onto the biotinylated dendrimer monolayer, and fluorescence images of the bound avidins were investigated with a confocal microscope. The constructed biospecific affinity surface showed a much more dense and uniform fluorescence compared to those from poly-L-lysine- and cystamine SAM-based affinity surfaces. For the dependency on the concentration of added FITC-labeled avidin on the affinity surface, derived fluorescence could be detectable from as low as $1{\mu}g/ml$, and intensified up to $50{\mu}g/ml$. Further reaction of FITC-labeled avidin layer with TMR(tetramethylrhodamine)-biocytins resulted in the efficient FRET(fluorescence resonance energy transfer) phenomenon. As an extension of the study, we attempted a patterning of the affinity surfaces on gold by microcontact printing. Fluorescence of the patterned surface demonstrated that FITC-labeled avidin molecules were specifically bound to the biotinylated patches.

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