• Title/Summary/Keyword: Fluorescent dyes

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Investigation of Fluorescent Shape Memory Polyurethanes Grafted with Various Dyes

  • Chung, Yong-Chan;Choi, Jae-Won;Lee, Seung-Hwan;Chun, Byoung-Chul
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.2988-2996
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    • 2011
  • Shape memory polyurethane (SMPU), grafted with a fluorescent dye (Rhodamine, Mehylene violet, or Fluorescein) through an allophanate linking, was tested for the fluorescence and the shape recovery effect. The main chain of SMPU was composed of 4,4'-methylenebis(phenylisocyanate) (MDI), poly(tetramethyleneglycol) (PTMG), and 1,4-butanediol (BD), and a fluorescent dye was connected through a second MDI linked to the carbamate moiety of the main chain. Three series of SMPU, differing according to their dye content, were prepared to compare their shape recovery and fluorescence properties. In tensile mechanical property, maximum stress increased up to 350% compared to the linear SMPU, and strain remained above 2000%. Shape recovery went to as high as 97%, and remained almost same after repetitive shape recovery test cycles. Finally, the fluorescence emission of SMPU was demonstrated in the luminescence spectrum and fluorescent light emission pictures. In addition, the response of SMPU to external stimuli such as metal ions was investigated.

Rhodamine 6G Based New Fluorophore Chemosensor Toward Hg2+

  • Son, Young-A;Park, June-Min
    • Textile Coloration and Finishing
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    • v.24 no.3
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    • pp.158-164
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    • 2012
  • Rhodamine dyes belong to xanthene family has excellent photostability and photophysical properties. In rhodamine dyes, Rhodamine 6G and its precursors also have xanthene chromophore and it shows high fluorescent quantum yield. Rhodamine 6G derivates are simple to synthesis and its high sensitivity and water solubility are suitable as good chemosensor. In this regard, Rhodamine 6G derivates which have selectivity to specific metal cation can used to detect various heavy metal ions. In this study, rhodamine 6G derivatives were synthesized by reaction of rhodamine 6G hydrazide and glyoxal and 4-phenyl thiosemicarbazide and it showed colorimetric and fluorescence sensing toward $Hg^{2+}$ ion. This novel chemosensor was analyzed and measured on UV-Vis and fluorescence spectrophotometer. HOMO/LUMO values were also calculated by computational calculation.

Study on characteristics of Red OLED doped with rubrene (rubrene을 도핑한 Red OLED 특성 연구)

  • Lee, Jeong-Ho;Jeong, Ji-Hun;Kim, Yeong-Gwan
    • Proceedings of the Optical Society of Korea Conference
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    • 2005.02a
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    • pp.166-167
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    • 2005
  • The doping technique has been well known as method to get various emission color by choosing appropriate fluorescent dyes as a dopant. Usually, red emission of OLED device based on Alg$_{3}$ doped with DCM and rubrene is fabricated. Result that fabricate OLED device was manufactured by various doping density, we looked for the doping ratio of highest luminescent efficiency.

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Multiparameter Flow Cytometry: Advances in High Resolution Analysis

  • O'Donnell, Erika A.;Ernst, David N.;Hingorani, Ravi
    • IMMUNE NETWORK
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    • v.13 no.2
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    • pp.43-54
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    • 2013
  • Over the past 40 years, flow cytometry has emerged as a leading, application-rich technology that supports high-resolution characterization of individual cells which function in complex cellular networks such as the immune system. This brief overview highlights advances in multiparameter flow cytometric technologies and reagent applications for characterization and functional analysis of cells modulating the immune network. These advances significantly support highthroughput and high-content analyses and enable an integrated understanding of the cellular and molecular interactions that underlie complex biological systems.

Detection of rare point mutation via allele-specific amplification in emulsion PCR

  • Cheng, Changming;Zhou, Yin;Yang, Chao;Chen, Juan;Wang, Jie;Zhang, Jie;Zhao, Guoping
    • BMB Reports
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    • v.46 no.5
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    • pp.270-275
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    • 2013
  • It is essential to analyze rare mutations in many fields of biomedical research. However, the detection of rare mutations is usually failed due to the interference of predominant wild-type DNA surrounded. Herein we describe a sensitive and facile method of detecting rare point mutation on the basis of allele-specific amplification in emulsion PCR. The identification and selective amplification of rare mutation are accomplished in one-pot reaction. The allele-specific primers coupled on magnetic beads allow the exclusive amplification and enrichment of the mutant amplicons. The productive beads bearing mutant amplicons are subsequently stained with the fluorescent dyes. Thus, the rare point mutations with a percentage as low as 0.1%, can be detected by fluorescent analysis. The relative percentages of mutation among different samples can be roughly accessed by counting the fraction of fluorescent positive beads through flow cytometry.

Applying Fluorescent Whitening Agent and Tinting Dye on Paper

  • Wang Li-Jun;Chen Fu-Shan;An Kook-Hun;Yoon Byung-Ho
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2004.11a
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    • pp.100-105
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    • 2004
  • The difference of whiteness, brightness and lightness was clearly explained in this paper through the use of a tinting dye and a fluorescent whitening agent which are commercially wide]y used to make paper look whiter. Other optical properties such as tint, color shade, and color difference were also discussed. It was suggested that in comparing two tinting dyes, lightness $(L^*)$ is the most important property to be compared, while whiteness data should be used in caution in order not to surpass its significant range, and $a^*,\;b^*$ values can also be used to see the change of color shades together with ${\Delta}E$ as color difference. In comparing two fluorescent whitening agents, whiteness or brightness values are most important to be compared, but lightness values are not suitable fur this purpose; $a^*,\;b^*$ and color difference ${\Delta}E$ can also be referred, but with less significance.

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Fabrication and Mechanical Properties of Carbon Nanotube Probe for Ultrasmall Force Measurement in Biological Application (생물학적 초미세력 검출을 위한 탄소나노튜브 프로브의 제작 및 기계적 특성 검출)

  • Kwon, Soon-Geun;Park, Hyo-Jun;Lee, Hyung-Woo;Kwak, Yoon-Keun;Kim, Soo-Hyun
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.5
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    • pp.140-147
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    • 2008
  • In this study, a carbon nanotube probe (CNT probe) is proposed as a mechanical force transducer for the measurement of pico-Newton (pN) order force in biological applications. In order to measure nantube's displacement in the air or liquid environment, the fabrication of a CNT probe with tip-specific loading of fluorescent dyes is performed using tip- specific functionalization of the nanotube and chemical bonding between dyes and nanotube. Also, we experimentally investigated the mechanical properties of the CNT probe using electrostatic actuation and fluorescence microscope measurement. Using fluorescence measurement of the tip deflection according to the applied voltage, we optimized the bending stiffness of the CNT probe, therefore determined the spring constant of the CNT probe. The results show that the spring constant of CNT probes is as small as 1 pN/nm and CNT probes can be used to measure pN order force.

HISTOLOGIC EvALUATION OF BONE HEALING AROUND TITANIUM PLASMA SPRAYED AND HYDROXYAPATITE-COATED IMPLANTS IN DOGS (성경 대퇴골에 매식된 Titanium Plasma Spray 및 Hydroxyapatite 피복임프란트 주위의 골치유 양상)

  • Huh, Ki-Nam;Chung, Hyun-Ju
    • Journal of Periodontal and Implant Science
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    • v.25 no.2
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    • pp.418-437
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    • 1995
  • The effect of the hydroxyapatite coatings on Titanium implants has been the subject of recent investigations. So far, the use of HA coating remains substantially controversial.This study was aimed to evaluate histologically the bone healing patterns around titanium plasm sprayed(TPS) amd HA-coated implant after implantation into the femur neck of ten adult dogs. After implantation, animals were sacrificed at the intervals of 2,4,6,8 and 12 weeks.The fluorescent dyes were injected on the postoperative 4th and 12th week into the animals supposed to be killed at the 12th week. The morphology and direction of new bone formation was similar in both TPS and HA-coated implants.There was a tendency toward more bone formation in the cortical bone area than in the cancellous bone area. Histologically,in the interface of the HA-coated implants, bone response and bone maturation was faster, compared to the TPS implants in the 2nd and 4th week. By fluorescent microscopy, new bone formation was active in the 4th week around both implants and was directed from the periosteum overlying cortical bone to the cancellous bone. These results suggest that the bone formation and maturation is faster during the early healing stage in the interface of the HA-coated implant and where the cortical bone quality is poor, HA coated implant is superior to the TPS implant in the early phase of new bone formation.

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A SPECTROSCOPIC STUDY OF THE OPTICAL PROPERTIES OF VARIOUS PAPERS MADE FROM RECLAIMED FIBRES

  • Ingegerd Forsskahl;Carola Olkkonen;Henrik Tylli
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 1999.04b
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    • pp.296-301
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    • 1999
  • Different papers such as toilet and towel tissue, newsprint and copy paper made from reclaimed fibres were characterized using UV-VIS reflectance and fluorescence spectroscopy. The emission properties of the extracts of the papers were also evaluated. Photochemical irradiation at ambient temperatures, and thermal aging of the copy papers at 105$^{\circ}C$ and 150$^{\circ}C$ were performed. Post-colour numbers (PC) were calculated from the reflectance values measured from the corresponding UV-VIS reflectance spectra. Light absorption coefficient spectra were calculated before and after irradiation, and the changes in absorption coefficient were related to the content of chromophores in the papers. Photochemical and thermal discolouration of the copy papers, similar to that of virgin fibres, was readily observed. The influence of changes in the concentrations of fluorescent brightening agents and dyes on the spectral properties was also assessed. Photostabilization studies of the copy papers were performed with the use of polymer additives polyethylene glycol (PEG) and polytetrahydrofuran (PTHF).

Influence of Fluorescent Dye Doping on Efficiency of Red Organic Light-emitting Diodes (형광염료 도핑이 적색 유기 발광 소자의 효율에 미치는 영향)

  • Lee, Jeong-Gu;Lim, Kee-Joe
    • The Journal of the Korea Contents Association
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    • v.8 no.11
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    • pp.18-24
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    • 2008
  • An organic light-emitting diode(OLED) has advantages of low power driving, self light-emitting, wide viewing angle, excellent high resolution, full color, high reproduction, fast response speed, simple manufacturing process, or the like. However, there are still a number of challenges to get over in order to put it to practical use as a high performance display. First of all, the most important thing is to improve the efficiency of the OLED element in order to commercialize it. To this end, its efficiency can be improved by lowering the driving voltage through the improvement of structure of the OLED element and the application of new organic substance. Therefore, in this study, we have manufactured a red OLED element by applying fluorescent dyes to the emitting layer of the element having the structure of ITO/TPD/ Znq2+DCJTB /Znq2/Al and the structure of ITO/CuPc/NPB/ Alq3+DCJTB/Alq3/Al, in order to light-emitting various colors or improve the brightness and the efficiency, and then we have evaluated its electrical and optical characteristics.