• Journal of Microbiology and Biotechnology
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• 제8권4호
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• pp.416-421
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• 1998

A carboxyl group modifier, l-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) was used to study the interactions between three components of toluene dioxygenase (TDO) from Pseudomonas putida FI. $Ferredoxin_{TOL}$ activity was increased by the treatment with EDC; however, the activity was rapidly declined in the prolonged incubation. In covalent cross-linking experiments with EDC, $Ferredoxin_{TOL}$ made a one-to-one complex with $Reductase_{TOL}$ or the large subunit of $ISP_{TOL}$. These results provide evidence for the involvement of electrostatic interactions in the TDO electron transfer system.

• 약학회지
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• 제40권4호
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• pp.442-448
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• 1996

Mitomycin C(MMC) has been used as an anticancer drug and behaves as an alkylating agent forming covalent cross-link between complementary strands of double strand DNA. The purpose of this research was to determine number of DNA adducts, formed in vivo by Mitomycin C, in mouse organs. DNAs from liver, lung, brain and pancreas were isolated and used for $^{32}P$-postlabelling. The labeled nucleotides were separated by 2D-TLC and subjected to autoradiography. Numbers of MMC-DNA adducts were 9,9,5,4 in liver, pancreas, lung and brain, respectively.

• 접착 및 계면
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• 제4권2호
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• pp.10-20
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• 2003

This paper is relative to the electroless deposition of nickel or copper films on polyimide and polytetrafluoroethylene substrates. First, it is presented an original approach of the electroless process which consists in grafting nitrogenated functionalities on the polymer surfaces via plasma or VUV-assisted treatments operating in a nitrogen-based atmosphere ($NH_3$, $N_2$), and then in catalysing the grafted surfaces in an aqueous tin-free, Pd(+2)-based solution. Adhesion of the Pd(+2) catalytic species on polymer surfaces is explained by the formation of strong covalent bonds between these species and the grafted nitrogenated groups. Second, it is show how a fragmentation test performed in conjunction with electrical measurements can be used to characterize the practical adhesion of the electroless coatings deposited on flexible polymer substrates, and to evidence the influence of some experimental parameters (plasma treatment time and nature of the gas phase).

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.9.2-9.2
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• 2011

Ultrathin polyelectrolyte (PE) multilayer films prepared by the versatile layer-by layer (LbL) assembly method have been utilized for the preparation of light-emitting diodes, electrochromic, membrane, and drug delivery system, as well as for selective area patterning and particle surface modification because the various materials with specific properties can be inserted into the film with nano-level thickness irrespective of the size or the shape of substrate. Since the introduction of the LbL technique in 1991 by Decher and Hong, various hydrophilic materials can be inserted within LbL films through complementary interactions (i.e., electrostatic, hydrogen-bonding or covalent interaction). In this study, it is demonstrated that LbL SA multilayer films based on nucleophilic substitution reaction can allow the preparation of the highly efficient magnetic and/or optical films and nonvolatile memory devices.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.303-303
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• 2006

In-situ ring opening polymerization of ${\varepsilon}-caprolactum$ was carried out in the presence of aminoethylaminopropylisobutyl POSS and stoichiometric amount of adipic acid. The covalent bond formation of POSS on the polyamide was confirmed by the appearance of FT-IR peak at $1123\;cm^{-1}$ that corresponds to the Si-O stretching of POSS structures. Gradual decrease in melting endotherm peak was observed on loading POSS in PA6/POSS nanocomposites. Sharp increase in intrinsic viscosity was observed upto 2.5 wt % loading POSS in the polyamide 6 nanocomposites. These nanocomposites were further characterized using nuclear magnetic resonance, melt viscosity and X-ray diffraction.

• 대한화학회지
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• 제26권3호
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• pp.148-154
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• 1982

수용액중에서 Nd(III)와 Ho(III) 이온의 hypersensitive 전이대의 oscillator strength에 미치는 몇가지 리간드의 효과를 연구하였다. 이때에 사용한 리간드는 furoate, anthranilate와 squarate이다. 각 착화합물에 있어서 금속-리간드 결합간에 존재하는 공유결합성을 리간드의 $pK_a$와 착화합물의 hypersensitive 전이대의 oscillator strength 사이에 정립된 관계에 근거를 두고 논하였다.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.749-752
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• 2013

Trehalose-tethered monomeric and dimeric berberines were synthesized in 50% and 30% from the reaction of berberrubine with 6-tosyl-${\alpha}$,${\alpha}^{\prime}$-trehalose and 6,6'-ditosyl-${\alpha}$,${\alpha}^{\prime}$-trehalose, respectively, and fully characterized by MS (HR and ESI) and NMR ($^1H$, $^{13}C$, COSY and HSQC). Spectrophotometric and spectrofluorimetric titrations indicated that compared with berberine, trehalose-tethered monomeric berberine had comparable DNA-binding affinity toward calf-thymus DNA, whereas trehalose-spaced dimeric berberine exhibited higher DNA-binding affinity. The potential application of these conjugates is also briefly discussed.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3722-3726
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• 2013

Covalent functionalization of a $Zn_{12}O_{12}$ nano-cage with $CO_2$ molecule in terms of energetic, geometry, and electronic properties was investigated by density functional theory method. For chemisorption configurations, the adsorption energy of $CO_2$ on the $Zn_{12}O_{12}$ nano-cage for the first $CO_2$ was calculated -1.25 eV with a charge transfer of 1.00|e| from the nano-cage to the $CO_2$ molecule. The results show that $CO_2$ molecule was significantly detected by pristine $Zn_{12}O_{12}$ nano-cage, therefore the nano-cage can be used as $CO_2$ storage. Also, more efficient binding could not be achieved by increasing the $CO_2$ concentration. For Physisorption configurations, HOMO-LUMO gap of the configurations has not changed, while slight changes have been observed in the chemisorption configurations.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1998년도 봄 학술발표회 논문집
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• pp.28-31
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• 1998

Photoresponsive polymers are being intensely investigated over last two decades, which can be attributed to both fundamental and applied significance. Presently the attention is being directed to these materials in view of their possible application in nonlinear optics and optoelectronics. It was demnstrated quite early that by covalent fixation of both photochromic group and the mesogenic group to the same polymer main chain high concentration of photochromic group can be attained.(omitted)

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권4호
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• pp.263-267
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• 2003

Magnetic nanoparticles prepared from an alkaline solution of divalent and trivalent iron ions could covalently bind protein via the activation of Nethyl-N-(3-dimethylaminopropyl) carbodiimide (EDC). Trypsin and avidin were taken as the model proteins for the formation of protein-nanoparticle conjugates. The immobilized yield of protein increased with molar ratio of EDC/nanoparticie. Higher concentrations of added protein could yield higher immobilized protein densities on the particles. In contrast to EDC, the yields of protein immobilization via the a ctivation of cyanamide were relatively lower. Nanoparticles bound with avidin could attach a single-stranded DNA through the avidin-biotin interaction and hybridize with a DNA probe. The DNA hybridization was confirmed by fluorescence microscopy observations. Immobilized DNA on nanoparticles by this technique may have widespread applicability to the detection of specific nucleic acid sequence and targeting of DNA to particular cells.