• 제목/요약/키워드: conjugated

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Various Sensor Applications Based on Conjugated Polymers

  • Lee, Chang-Lyoul
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.103.1-103.1
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    • 2014
  • Due to their excellent optical and electrochemical properties, conjugated polymers have attracted much attention over the last two decades and employed to opto-electrical devices. In particular, conjugated polymers possess many attractive features that make them suitable for a variety of sensing task. For example, their delocalized electronic structures can be strongly modified by varying the surrounding environment, which significantly affected molecular energy level. In other word, conjugated polymers can detect and transduce the environmental information into a fluorescence signal. Conjugated polymers also display amplified quenching compared to small molecule counterparts. This amplified fluorescence quenching is attributed to the delocalization and migration of the excitons along the conjugated polymer backbones. Long backbones of conjugated polymer provide the transporting path for electron as a conduit, allowing that excitons migrate rapidly into quencher site along the backbone. This is often referred to as the molecular wire effect or antenna effect. Moreover, structures of conjugated polymers can be easily tailored to adjust solubility, absorption/emission properties, and regulation of electron/energy transfer. Based on this versatility, conjugated polymers have been utilized to many novel sensory platforms as a promising material. In this tutorial, I will highlight a variety of fluorescence sensors base on conjugated polymer and explain their sensory mechanism together with selected examples from reference literatures.

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우레아 분별된 들기름 가수 분해물을 이용한 Conjugated Linolenic Acid(CLnA)의 합성 (Preparation of Conjugated Linolenic Acid from Urea Fractionated Perilla Seed Oil Hydrolysate)

  • 이경수;신정아;이기택
    • 한국식품영양과학회지
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    • 제40권12호
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    • pp.1734-1742
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    • 2011
  • 본 실험에서는 들기름에 약 60%로 존재하는 ${\alpha}$-linolenic acid를 알칼리 이성질화 반응을 이용하여 CLnA(conjugated linolenic acid)와 CLA(conjugated linoleic acid)를 생산하고자 하였다. 들기름을 가수분해한 뒤에 10분에서 6시간까지의 반응시간과 5%에서 60%까지의 NaOH 농도에서 CLnA와 CLA의 생성을 표준물질과 함께 GC와 spectrophotometer를 이용하여 확인하였다. 시간에 따른 CLnA와 CLA 함량 변화는 나타나지 않았으나, NaOH 농도가 증가함에 따라서 CLnA와 CLA가 유의적으로 증가하는 경향을 보였다. 반응조건 중, 20% KOH, $180^{\circ}C$, 1시간 반응에서 14.5%와 14%의 CLnA와 CLA의 함량을 나타냈으며, 42.2%의 C18:3 conjugated 이성질체가 생성되었다. 이성질체를 확인하기 위해 GC-MS 그리고 FT-IR을 이용한 실험을 수행하였다. GC-MS의 ion peak 분석 결과, conjugated 형태에서만 특징적으로 나타나는 m/z=91 ion peak를 확인할 수 있었고, CLA와 CLnA의 분자량이 C18:2와 C18:3과 일치하는 것을 확인할 수 있었다. 그리고 NIST Library에서 검색된 methyl 9c, 11t-CLA, methyl 10t, 12c-CLA와 methyl 9cis, 11trans, 13trans-octadecatrienoate의 결과와 일치하는 ion peak를 형성하였다. 이 외의 이성질체는 FT-IR 분석 결과, 높은 trans fatty acid 함량을 보여 알칼리 이성질화 반응 시, $180^{\circ}C$의 높은 열에 반응을 하여 trans 형태의 conjugated form이 다량 생성된 것으로 사료된다. conjugated 이성질체의 생성 양을 높이기 위해 들기름 가수분해물을 우레아 분별을 한 뒤에, ${\alpha}$-linolenic acid의 함량을 70%까지 높인 뒤에 알칼리 이성질화 반응을 수행한 결과 CLnA의 생성 양이 16.6%까지 증가한 것을 확인할 수 있었다. 그러나 CLnA 이외의 conjugated 지방산 함량의 변화는 없었다.

Macrophage의 IL-1$\beta$Gene Expression 대한 Lectin-conjugated Ellagitannin의 효과 (Effects of Lectin-conjugated Ellagitannin on the IL-1$\beta$, Gene Expression of Macrophage)

  • 김한준;김민수;이민원;최영욱;김하형;이도익
    • 약학회지
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    • 제46권3호
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    • pp.197-202
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    • 2002
  • Lectin-conjugated praecoxin A, which has developed as a missile antitumor drug, is the one that has conjugated with wheat germ agglutinin (WGA), a kind of carbohydrate-binding protein (lectin) especially bound to melanoma. Praecoxin A is a kind of tannin extracted and purified from plants. Beside this direct antitumor effect as tannins, we have examined an activation of macrophage by lectin-conjugated praecoxin A. We also confirmed the gene expression of IL-1 $\beta$, both in vitro and in vivo. We added 1, 10, 100 $\mu\textrm{g}$/mι of lectin-conjugated praecoxin A, 10 $\mu\textrm{g}$/mι of lectin, 10 $\mu\textrm{g}$/mι of praecoxin A to normal murine macrophage and analyzed the extracted total RNAs by RT-PCR after 4, 8, 12, 24 hours. Our data demonstrated that lectin-conjugated praecoxin A increased IL-1$\beta$, mRNA expression in a dose dependent manner. However, the effectiveness of lectin-conjugated praecoxin A was not superior to lectin and praecoxin A.

Bioactivities and Potential Mechanisms of Action for Conjugated Fatty Acids

  • Park, Yeon-Hwa;Pariza, Michael W.
    • Food Science and Biotechnology
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    • 제18권3호
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    • pp.586-593
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    • 2009
  • Since conjugated linoleic acid (CLA) was identified as a principal anticancer component from ground beef in the 1980s, CLA research has discovered that CLA has a wide range of biologically beneficial effects. Clinical studies with CLA are on the rise, and it is apparent that CLA may not be as effective in humans as in rodents, in particular its anti-obesity aspect. In addition, research with regard to other conjugated fatty acids as well as CLA metabolites is still in its infancy. Investigation of bioactivities for other conjugated fatty acids and CLA metabolites may help to extend the understanding of CLA and its mechanisms of actions. This may pose an opportunity to use CLA more efficiently and expand the future use of other conjugated fatty acids as pharmacological agents to assist current treatments.

Lectin-conjugated Ellagitannin의 흑색종에 대한 전이억제효과 (Effects of Lectin-conjugated Ellagitannin on Inhibition of Melanoma Metastasis)

  • 김형근;한기숙;이도익
    • 약학회지
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    • 제44권6호
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    • pp.601-606
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    • 2000
  • Recently, studies on missile antitumor drugs, which selectively act on tumor cell and display drug effects, have been performed. These missile antitumor drugs which can increase drug effects and decrease side effects, are ideal medication method. Lectin has been reported as tumor cell specific binding protein and tannin as antitumor substance. In this study, we studied inhibition of melanoma metastasis by lectin-conjugated ellagitannin and used praecoxin A as ellagitannin source. Mouse melanoma cell, B16-F10, was injected into the sole of forefoot of C57BL/6 mouse, and after administration with drug, the number of pulmonary tumor colony was counted. The administration of praecoxin A, lectin-praecoxin A mixiture, and lectin-conjugated praecoxin A was started after amputation of established tumor foci at right forefoot of mice and continued for 3 weeks with i.p. injection of one of those drugs A every 24 hours. Lectin-praecoxin A mixture, and lectin-conjugated praecoxin A significantly reduced the number of spontaneous pulmonary metastasis. Exposure to 5 mg/kg of lectin-praecoxin A mixiture and lectin-conjugated praecoxin A produced a statistically significant 38.3%, 41.8% reduction in the number of remaining pulmonary metastasis. These results suggest that metastasis inhibition by lectin-praecoxin A mixiture and lectin-conjugated praecoxin A are better than that of praecoxin A.

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반추위에서 분리한 곰팡이의 Conjugated Linoleic Acid 생산과 ITS-1 영역의 염기서열 해석 (Isolation and Identification of Rumen Fungus and Its Produced Conjugated Linoleic Acid)

  • 남인식
    • 미생물학회지
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    • 제43권2호
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    • pp.111-115
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    • 2007
  • 반추위에서 분리한 곰팡이(IS-13)의 conjugated linoleic acid 생산 과정을 조사하고conjugated linoleic acid를 생산하는 곰팡이를 동정하기 위하여 본 연구를 실시하였다. IS-13 곰팡이가 함유된 배양액에 linoleic acid를 첨가한 결과 linoleic acid는 배양 12시간 이내에 conjugated linoleic acid와 trans-11 vaccenic acid로 biohydrogenation되었다. IS-13 곰팡이의 동정은 internal transcribed spacer 1 영역(ITS1)을 sequence하여 GenBank 유래의 관련 23속(종)의 반추위 곰팡이와 비교하였다. IS-13 곰팡이의 ITS1의 length는 218 bp인 것으로 확인되었으며, 염기서열 분석 결과 Orpinomyces species와 98% 일치하여 반추위내 Orpinomyces species는 conjugated linoleic acid 생산에 깊이 관여하는 것으로 확인되었다. 연구결과 본 균주는 Orpinomyces 속에 속하는 균으로 동정되었다.

Binding Affinities of Carbohydrate-Conjugated Chlorins for Galectin-3

  • Park, Young K.;Bold, Bayarmaa;Cui, Bing Cun;Bai, Jin Quan;Lee, Woo-Kyoung;Shim, Young-Key
    • Bulletin of the Korean Chemical Society
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    • 제29권1호
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    • pp.130-134
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    • 2008
  • Carbohydrate-conjugated chlorins were synthesized for use as biosensors for the detection of the galectin-3 cancer marker. We used ELISA, SDS-gel electrophoresis, and Bradford assays to examine the binding of galectins to d-(+)-galactose- and b-lactose-conjugated chlorins. The binding affinities of these conjugated chlorins for galectin-3 were quantified using fluorescence spectroscopy. The fluorescence emission of the carbohydrate-conjugated chlorins decreased as the amount of galectin-3 in the binding reaction increased over a limited concentration range, indicating that carbohydrate-conjugated chlorins are potentially useful fluorescence biosensors for the galectin-3 cancer marker.

알카리 및 산촉매법(酸觸媒法)에 의한 conjugated triene 지방산(脂肪酸) 잔기(殘基)을 함유(含有)한 트리글리세리드의 메칠 에스틸화(化)의 비교(比較) (Methyl Ester Preparation from Triacylglycerols Containing Conjugated Trienoic Fatty Acids, by Alkaline and Acid Catalyst)

  • 조용계
    • 한국응용과학기술학회지
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    • 제12권1호
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    • pp.119-124
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    • 1995
  • Conventional alkaline catalytic procedure, including sodium methoxide-methanol N, N, N', N'-tetramethyl guanidine-methanol, and acid-catalytic methods of $BF_{3}-methanol$ and HCI-methanol, have been applied for preparing methyl esters from the triacylglycerols of Trichosanthes kirilowiil seeds containing conjugated trienoic acids. The alkaline catalytic methods produce the methyl esters quantitatively without isomerization of the conjugated trienoic acids, but the acid-catalytic ones destroy almost the molecules of conjugated trienoic acids during transesterification of the triacylglycerols although the molar ratios of monoenoic and dienoic acids (non-conjugated) to saturated acids are in good agreement with those obtained from the alkaline methods.

Lectin-conjugated Ellagitannin의 혹색종에 대한 항암활성 (Effects of Lectin-conjugated Ellagitannin on Antitumor Activity)

  • 김형근;한기숙;이도익
    • 약학회지
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    • 제44권6호
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    • pp.607-612
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    • 2000
  • Generally, antitumor drugs have strong toxicity and result in damage in normal cells. Previously, lectin has been reported as a tumor cell specific binding protein and tannin as an antitumor substance. In this study, we investigated antitumor activity of lectin-conjugated ellagitannin and used praecoxin A as an ellagitannin source. We injected mouse melanoma cell, B16-F10, on right the femoral region of C57BL/6 mouse. After 10 hours later, first treatment with praecoxin A, lectin-praecoxin A mixiture and lectin-conjugated praecoxin A was carried and followed by injection i.m. every 48 hours. Praecoxin A extended the life of mice up to 14.8% in comparison with the negative control group at 5 mg/kg dose. The life extending ratio of Lectin-praecoxin A mixture was 26.1% at 5 mg/kg dose, and the life extending ratio of lectin-conjugated praecoxin A was 28.7% at 5 mg/kg dose. On the basis of these findings, we suggest that antitumor activities of lectin-praecoxin A mixiture and lectin-conjugated praecoxin A on survival are better than that of praecoxin A.

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Fluorescence Tuning Using Conjugated Aromatic Imine Systems

  • Lee, Ki-Hwan;Park, Chang-Shik;Jeon, Ki-Seok
    • Journal of Photoscience
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    • 제9권3호
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    • pp.71-74
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    • 2002
  • The fluorescent conjugated aromatic imine derivatives are systematically designed and synthesized as the high yield through the simple one-pot condensation reaction. The emission of the synthesized conjugated aromatic imine derivatives can be tuned efficiently in the range of about 100 nm by the change of electron donating groups constituting parent molecule, which shows the considerable quantum yields from 0.38 to 0.56.

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