• 한국염색가공학회지
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• 제27권4호
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• pp.275-280
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• 2015

New series of phthaloperinone dyes were synthesized by the condensation reaction between tetrachloro-phthalic anhydride, 2,3-naphthalene dicarboxylic anhydride and o-phenylenediamine, 1,8-diaminonaphthalene, 1,2-diaminoanthraquinone. These dyes absorb at around 370-490nm. It was found that introduction of naphthalene and anthraquinone moiety on the perinone system produces a large bathochromic shift of 100nm. The synthesized dye 7 containing anthraquinone moiety in perinone chromophoric system exhibited superior heat stability and bright color as yellow chromophore. New dye 7 have been investigated in terms of interacting with volatile organic compound(VOC) $EtNH_2$. The sensing behaviour of the dye 7 toward $EtNH_2$ was studied by UV-vis absorption spectroscopy. Sensing mechanism of dye 7 to $EtNH_2$ was supported by theoretical calculations based on DFT method.

• 폴리머
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• 제28권6호
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• pp.545-550
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• 2004

광조사에 의하여 발색단 분해를 유도함으로써 고분자의 굴절률을 변화시켜 공중합체 박막의 굴절률을 조절하고, FTIR과 UV/Vis 분광 실험으로 굴절률에 영향을 미치는 구조의 변화를 조사하였다. 광표백에 따라 공중합체 박막의 굴절률이 작아지는 것은 광반응에 의하여 발색단 내 C=C 이중결합이 끊어져 고분자의 편극률이 작아지기 때문이다. 입사되는 빛의 전기장 방향에 의존하는 선택적인 광반응에 의하여 필름 면에 평행한 방향으로 존재하는 발색단이 먼저 분해가 되면서 고분자 필름 면에 평행한 방향의 굴절률이 수직한 방향에서 보다 더 급격하게 감소하였다. 이와 같은 고분자 박막 내의 굴절률 차이를 편광 ATR-FTIR 실험에서 얻어지는 고분자 특성 피크의 변화를 조사하여 증명하였다.

• Macromolecular Research
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• 제11권4호
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• pp.250-255
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• 2003

We prepared the photorefractive sol-gel glass based on organic-inorganic hybrid materials containing a charge transporting molecule, second-order nonlinear optical (NLO) chromophore, photosensitizer, and plasticizer. Carbazole and 2-{ 4-[(2-hydroxy-ethyl)-methyl-amino]-benzylidene}-malononitrile were reacted with isocyanato-triethoxy silane and the functionalized silanes were employed to fabricate the efficient photorefractive media induding 2,4,7-trinitrot1uorenone (TNF) to form a charge transfer complex. The prepared sol-gel glass samples showed a large net gain coefficient and high diffraction efficiency at a certain composition. As the concentration of photosensitizer increased, the photorefractive properties were enhanced due to an increment of charge carrier density. Dynamic behavior of the diffraction efficiency was also investigated with the concentration of the photosensitizer.

• Journal of Microbiology and Biotechnology
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• 제25권4호
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• pp.503-510
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• 2015

The iLOV protein belongs to a family of blue-light photoreceptor proteins containing a light-oxygen-voltage sensing domain with a noncovalently bound flavin mononucleotide (FMN) as its chromophore. Owing to advantages such as its small size, oxygen-independent nature, and pH stability, iLOV is an ideal candidate over other reporter fluorescent proteins such as GFP and DsRed. Here, for the first time, we describe the feasibility of applying LOV domain-based fluorescent iLOV as a metal sensor by measuring the fluorescence quenching of a protein with respect to the concentration of metal ions. In the present study, we demonstrated the inherent copper sensing property of the iLOV protein and identified the possible amino acids responsible for metal binding. The fluorescence quenching upon exposure to Cu²⁺ was highly sensitive and exhibited reversibility upon the addition of the metal chelator EDTA. The copper binding constant was found to be 4.72 ± 0.84 µM. In addition, Cu²⁺-bound iLOV showed high fluorescence quenching at near physiological pH. Further computational analysis yielded a better insight into understanding the possible amino acids responsible for Cu²⁺ binding with the iLOV protein.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.50-58
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• 2014

A novel fullerene derivative with photoresponsive azobenzene group was designed and synthesized, and its photoresponsive properties were reported. Starting from 4-nitrophenol, compound 1, which is containing fullerene moiety connected to azobenzene group through covalent linkage was synthesized by 5 steps. All the intermediates and the final compound were characterized by $^1H$, $^{13}C$-NMR, FAB-Mass or elemental analysis. Compound 1 exhibited the expected photoresponsive behavior. Chloroform solution($10^{-5}M$) of it served to maximize the absorption at 351 nm corresponding to the trans-azobenzene chromophore. Irradiation of this solution with 365 nm light resulted in photoisomerization to cis-azobenzene, as evidenced by decrease in the absorbance at 351 nm and an increase in absorbance at 450nm. A photostationary state was reached within about 150 s. Thermal reversion to the original spectrum was observed over the course of about 6 h at room temperature in the dark. However, exposure to bright sun light for about 5 s also effect almost complete reversion to the trans-isomer. This indicates that there is no strong steric influence on the trans-cis reversible isomerization of compound 1.

• Bulletin of the Korean Chemical Society
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• 제24권12호
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• pp.1793-1798
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• 2003

A series of amorphous molecules that possess both photoconductive and electro-optic properties was synthesized in order to investigate photorefractive properties of bifunctional organic-glasses. Diethylaminobenzaldehyde-diphenylhydrazone was covalently attached to 5-(4-diethylamino-benzylidene)-1,3-dimethylpyrimidine-2,4,6-trione through a flexible alkyl chain (3, 4, 5, 6 and 10 carbons) containing two ether linkages. The longer linkage not only lowered the glass transition temperature ($T_g$) of the molecules, but also allowed faster orientation of the chromophore. To examine the photorefractive properties, a 50 ${\mu}$m-thick film was prepared from the mixture of a bifunctional molecule, butyl benzyl phthalate, and $C_{60}$. The photoconductivity of this composite was as high as $8.01\;{\times}\;10^{-12}$ S/cm at 60 V/ ${\mu}$m, and the maximum diffraction efficiency ( ${\eta}_{max}$) of 50 ${\mu}$m-thick film was about 5% at 80 V/ ${\mu}$m.

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.77-84
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• 2005

We prepared the new nonlinear optical chromophores that show fairly high microscopic nonlinearity through intramolecular charge transfer. Phenothiazine and carbazole units played an important role to contribute high electron donability and connect the resonance pathway via conjugative effect in the cyclized ring beside the aromatic ring. Theoretical calculation, electrochemical analysis, and absorption spectroscopic study gave us useful information about the energy states and microscopic nonlinearities of two serial chromophores. We compared the microscopic nonlinearities of four chromophores with the conjugation length and electron donability in the push-pull type NLO chromophores. The effect of gradient donability and lengthening the conjugation were investigated on the electronic state and microscopic nonlinearity.

• 약학회지
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• 제41권6호
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• pp.718-723
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• 1997

In the course of developing novel antitumor intercalating agents, we synthesized 3- carbamoyloxymethyl-azaanthraquinones 6-12, incorporating the latent alkylating functionality. These compounds were designed to explore the effect of heteroatom incorporation into anthraquinone chromophore and the effect of the incorporation of the latent alkylating functionality. The derivatives were prepared by hetero Diels-Alder reaction as a key step followed by functionality of allylic methyl to the desired substituents. Growth inhibitory studies of the azaanthraquinones were conducted in vitro against human cancer cell lines (SNU-354: liver and MCF7: breast) and human epidermoid carcinoma cells that are sensitive (KB-3-1) and multidrug-resistant (KB-V-1). The derivatives were 10 to 100-fold less potent than doxorubicin against sensitive cell lines. However, they were marginally cross-resistant with doxorubicin against KB-V-1.

• 복식문화연구
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• 제12권4호
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• pp.579-590
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• 2004

This research was aimed to investigate and compare the effectiveness of TLC and GC-MS methods in the analysis of chromophoric substances extracted from madder plant. Alizarin and purpurin 0.3% solution were used as comparative standards; madder extraction was prepared by heating the solution of powdered madder at 80℃, pH 1.5, for 90 min. Best elution solvent for TLC in silica gel plate was toluene:ethyl acetate=9:1, which resulted in red and yellow spots from madder extraction each of which showed R/sub f/ values 0.32-0.43 and 0.07-0.11. Although the red spot in particular exhibited similar characteristics as standard purpurin in color, shape, and R/sub f/ values, the result was inconsistent throughout different TLC trials. GC-MS analysis showed only small amount of alizarin and no purpurin in the madder extraction. Other chromophoric substance such as 2-furancarboxaldehyde, 5-(hydroxymethyl)-, anthralin, and danthron were also detected in small amounts. The result indicated that TLC was less sensitive to detecting and identifying the natural dyestuff which is generally constituted with a number of similar but chemically different chromophoric substances.

• Molecules and Cells
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• 제39권6호
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• pp.460-467
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• 2016

Bacteriophytochromes are phytochrome-like light-sensing photoreceptors that use biliverdin as a chromophore. To study the biochemical properties of the Deinococcus radiodurans bacteriophytochrome (DrBphP) protein, two anti-DrBphP mouse monoclonal antibodies (2B8 and 3H7) were generated. Their specific epitopes were identified in our previous report. We present here fine epitope mapping of these two antibodies by using truncation and substitution of original epitope sequences in order to identify minimized epitope peptides. The previously reported original epitope sequences for 2B8 and 3H7 were truncated from both sides. Our analysis showed that the minimal peptide sequence lengths for 2B8 and 3H7 antibodies were nine amino acids (RDPLPFFPP) and six amino acids (PGEIEE), respectively. We further characterized these peptides in order to investigate their reactivity after single deletion and single substitution of the original peptides. We found that single-substituted 2B8 epitope (RDPLPAFPP) and dual-substituted 3H7 epitope (PGEIAD) showed significantly increased reactivity. These two antibodies with high reactivity for the short modified peptide sequences are valueble for developing new peptide tags for protein research.