• Title/Summary/Keyword: fluorescein

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SERS Study of Fluorescein Using the Silver Sol and Silver Mirror Substrates (Silver Sol과 Silver Mirror Substrate를 이용한 Fluorescein의 SERS 연구)

  • Lee, Chul-Jae;Choi, Hyun-Kuk;Jung, Maeng-Joon
    • Journal of the Korean Society of Industry Convergence
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    • v.10 no.1
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    • pp.27-32
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    • 2007
  • It has been recently reported that the SERS (Surface Enhanced Raman Scattering) effect of the silver mirror substrate made by Tollen's method is much superior to that of other substrates. In this study, the experiments for comparison of surface enhancement of silver sol and silver mirror substrates were done, where we checked the characteristics of silver mirror substrate made by Tollen's method. The surface enhancement of fluorescein was analyzed by silver sol and silver mirror substrates. We observed the SERS spectra of fluorescein. The assignments of the vibrational bands shown in SERS spectra are given based on both literature and the semi-empirical calculations at the PM3 methods. The surface enhancement properties for fluorescein showed that the silver mirror was more superior to sliver sol substrates. Spectra of fluorescein revealed that fluorescein was adsorbed on silver surfaces by a common oxygen atom. According to the 'surface selection rule', the vibrations in the band intensities reflect the adsorption orientation of the molecule on to the surface of SERS substrates. Therefore, we deduced that the adsorption orientation of fluorescein was little tilted perpendicular to the silver surfaces by using of the surface selection rules.

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A Case of Myelopathy after Intrathecal Injection of Fluorescein

  • Park, Kwang-Yeol;Kim, Young-Baeg
    • Journal of Korean Neurosurgical Society
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    • v.42 no.6
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    • pp.492-494
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    • 2007
  • We present a case with seizure, confusion, hypesthesia and paraplegia after intrathecal injection of fluorescein. A 41-year-old man was admitted to our institution for the management of the CSF leakage. Intrathecal injection of fluorescein was performed and he complained of severe pain and numbness in the lower extremities at the end of the injection. Four hours later, he exhibited confusion, paraparesis and two episodes of generalized seizures. Two days later, he showed paraplegia and all sensory modalities below the T12 level were absent. Spine magnetic resonance imaging revealed myelopathic change in the lower thoracic spinal cord. There was no improvement of weakness and sensory deficits in lower extremity even 14 days after fluorescein injection. We speculated that thoracic myelopathy was associated with the intrathecal injection of fluorescein. In spite of its rarity, the complication after intrathecal injection of fluorescein could be serious. Thus, obtaining an informed consent with discussion with patient before the procedure is mandatory.

Synthesis of Novel Fluorescent Dye Based on Fluorescein

  • Hwang, Ji-Yong;Son, Young-A
    • Textile Coloration and Finishing
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    • v.26 no.3
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    • pp.272-276
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    • 2014
  • The functional materials have been developed as a promising research topic toward the end uses for organic materials and applications. In this study, fluorescein based dye was synthesized by three step reaction. We have designed and synthesized the colorimetric dye through the reactions of fluorescein and methoxy group and ethylene diamine and squaric acid. The structure of the non-fluorescent spirolactam was elucidated by $^1H$-NMR, LC-Mass and FT-IR analyzes. Further studies are in progress to understand the effects of various substituent during the recognition process and to develop fluorescein based sensors for cations or anions.

Assay of Lipase Activity by the pH-Dependent Fluorescence Change of Fluorescein (Fluorescein 형광의 pH 의존성을 이용한 lipase 활성 측정방법)

  • Park, Jong-Won;Choi, Suk-Jung
    • Journal of Life Science
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    • v.18 no.8
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    • pp.1159-1163
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    • 2008
  • The purpose of this study was to establish a high-throughput assay method capable of estimating specific lipase activity at oil-water interface. The method is based on the fact that fluorescence intensity of fluorescein is affected by pH. The pH-dependence might be used to monitor pH change caused by the release of fatty acid through the action of lipase. Assay was performed by incubating a reaction mixture containing oil emulsion, fluorescein and enzyme and by monitoring fluorescence intensity periodically. Fluorescence intensity decreased linearly with a rate proportional to the enzyme amount. Linear relationship was observed between enzyme amount and reaction rate which was calculated from a graph of fluorescence change against time. The assay was possible at different pH conditions in the range of pH 6.0-8.0.

A FRET Assay for Celiac Disease

  • Lee, Sae A;Cho, Chul Min;Jang, Il Ho;Kang, Jung Sook
    • Biomedical Science Letters
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    • v.22 no.4
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    • pp.160-166
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    • 2016
  • To provide a basis for a homogeneous fluorescence resonance energy transfer (FRET) immunoassay for celiac disease, we carried out a FRET experiment using guinea pig tissue transglutaminase (tTG) and antibodies to tTG (anti-tTG) purified from rat serum. Fluorescein was utilized as the probe, and a nonfluorescent dye, QSY 7 served as the quencher. We labeled anti-tTG and tTG with fluorescein isothiocyanate and QSY 7 succinimidyl ester, respectively. Fluorescein-labeled anti-tTG was the donor, and QSY 7-labeled tTG was the acceptor of the FRET experiment. When we titrated fluorescein-labeled anti-tTG with QSY 7-labeled tTG, we observed a large decrease in the steady-state fluorescence intensity, which was due to strong FRET from fluorescein-labeled anti-tTG to QSY 7-labeled tTG. Using time-resolved fluorescence spectroscopy, we could also observe a decrease in the fluorescence lifetime, which confirms the steady-state data. We expect that these results might be useful in the development of a novel fluorescence immunoassay for an easy screening and follow-up of celiac patients.

The Distance-Dependent Fluorescence Enhancement Phenomena in Uniform Size Ag@SiO2@SiO2(dye) Nanocomposites

  • Arifin, Eric;Lee, Jin-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.539-544
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    • 2013
  • $Ag@SiO_2@SiO_2$(FITC) nanocomposites were prepared by the simple polyol process and St$\ddot{o}$ber method. Fluorescence enhancement of fluorescein moiety (fluorescein isothiocyanate, FITC) was investigated in the presence of silver nanoparticles in $Ag@SiO_2@SiO_2$(FITC) system with varying thickness (X nm) of first silica shell. Maximum enhancement factor of 4.3 fold was achieved in $Ag@SiO_2@SiO_2$(FITC) structure with the first silica shell thickness of 8 nm and the average separation distance of 11 nm between the surface of silver nanoparticle and fluorescein moiety. The enhancement is believed to be originated from increased excitation rate of fluorescein moiety due to concentrated local electromagnetic field which was improved by interaction of light with silver nanoparticles.

Binding of Lectins to the Zona Pellucida on Sperm-oocytes Interaction in the Pig (체외에서 돼지 정자-난자의 상호작용시 투명대내 Lectin 결합)

  • Hwang, In-Sun;Kim, Choung-Ik;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Clinical and Experimental Reproductive Medicine
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    • v.29 no.3
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    • pp.179-186
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    • 2002
  • Objective: Lectins are cell-agglutinating and sugar specific proteins or glycoproteins of non-immune origin that precipitate glycoconjugates having saccharides of appropriate complementarity. Because of these properties, plant lectins have been used to help characterize the carbohydrate moieties of glycoproteins in the zona pellucida (ZP) of several mammalian species including pigs. Treatment of oocytes with various lectins blocks sperm binding to the ZP in various mammalian species. This study was undertaken to examine the distribution of sugar residues in the ZP of pig oocytes matured in vitro and the ability of spermatozoa to bind to ZP and in vitro penetration in oocytes treated with fluorescein isothiocyanate (FITC)-labelled lectins. Materials and Methods: The lectins of Banderiaea simplicifolia (BS-II, bind to $\beta$-D-N-acetylglucosamine), Canavalin ensiformis (Con A, bind to $\alpha$-D-Mannose), Lens culinaris (LCA, bind to a-D-Mannose), Ricinus communis (RCA-I, bind to $\beta$-D-Galactose) and Ulex europaeus (UEA-I, bind to $\alpha$-L-Fucose) were examined for spermatozoa penetration, binding capacity to ZP and distribution of lectins. Results: The penetration rates were significantry (p<0.05) higher in control oocytes (63%) than those treated with all lectins, but penetration rates ($40{\sim}49%$) were simililar in group treated with lectins. The incidence of monospermy was similar in oocytes untreated and UEA-I, but it was higher in oocytes treated with BS-II, Con A, RCA-I and LCA. The porcine oocytes cultured for 48 h in TC-199 medium were freed from cumulus cells and treated for 30 min with fluorescein isothiocyanate-labelled lectins. When examined under fluorescein illumination, higher (p<0.001) proportions of oocytes showed fluorescein of zona pellucida after treatment with Con A (93%), LCA (93%) and RCA-I (100%) than BS-II (37%) and UEA-I (50%). All of the oocytes treated with RCA-I exhibited strong fluorescein in the outer region of the zona pellucida while those treated with LCA exhibited strong fluorescein throughout the zona pellucida. BS-II bounded mainly to the outer region and UEA-I bounded mainly to the inner region of the zona pellucida, with either strong or weak fluorescein. At 120 min after insemination in vitro, fewer spermatozoa were bound to the zona pellucida of the oocytes treated with BS-II, Con-A and RCA-I. Of the lectins, Con A most inhibited sperm binding. Conclusions: These results suggest that $\beta$-D-Galactose residues in the porcine zona pellucida may act as primary sperm receptors and inducers of the sperm acrosome reaction and these sugar residues may be involved in the block to polyspermy.