• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1599-1603
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• 2011

Novel chemosensors based on 2-(2'-hydroxyphenyl)quinoline were prepared and evaluated for sensing metal cations. The photophysical properties of chemosensors 1-3 were examined and their ion-selectivity was evaluated by measuring their fluorescent emission responses to alkali, alkaline earth, and transition metal ions. Chemosensors 1, 2 and 3 show ratiometric and enhanced fluorescence changes with transitional metals that are efficient fluorescence quenchers, especially 3 has a high binding constant with $Hg^{+2}$ in $CH_3CN$.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1093-1096
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• 2009

Two new chemosensors 1 and 2 derived from 5,12- and 5,7-dioxocyclams were prepared and their signaling behaviors toward transition metal ions were investigated. Chemosensors 1 and 2 showed very efficient responses toward $Cu_{2+}$ and $Hg_{2+}$ ions. Ratiometric analysis of the fluorescence changes in pyrene monomer and excimer emissions clearly demonstrated the $Cu_{2+}$- and $Hg_{2+}$-selective signaling behavior. The signaling mechanism of the chemosensors is due to conformation changes upon complexation with metal ions and the inherent quenching nature of the complexed $Cu_{2+}$ and $Hg_{2+}$ ions themselves.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.26-26
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• 2011

Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environment monitoring. Colorimetric chemosensor for pH sensing can easily detect the primary danger or change of the surrounding environment pollution and source of infection and can prevent danger in the various fields. Quinaldine and Indole based colorants having the function of colorimetric chemosensors were synthesized and applied to textiles by the LBL method and electrospinning. The characteristics of colorant containing nanofibers and colored textiles were investigated if they can be used as environmental monitoring chemosensors.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.9
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• pp.711-716
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• 2012

Based on both organic synthesis and theoretical calculations on the effects of molecular orbital energy levels of amines on the fluorescence properties of the fluorophore, fluorescent "turn-on" chemosensors detecting hazardous substances, including aldehyde chemicals and $Hg^{2+}$ ion, were developed.

• Journal of Environmental Science International
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• v.22 no.10
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• pp.1273-1278
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• 2013

Novel rhodamine 6G fluorescent chemosensors 1 and 2 for the detection of transition metal cations were synthesized through the condensation of rhodamine 6G ethylenediamine with each of 2-hydroxy-1-naphthaldehyde and 2,6-pyridinedicarbaldehyde, respectively. 1 and 2 were characterized using $^{13}C$ NMR, $^1H$ NMR and mass spectroscopy. Fluorometric and colorimetric measurements involving various metal ions revealed the ring opening of the rhodamine 6G spirocycle framework. In the absence of metal cations, 2 was colorless and non-fluorescent, whereas the addition of metal cations ($Hg^{2+}$ and others) changed the color to pink, accompanied by the appearance of an orange fluorescence. The chemosensors exhibited high selectivity for $Hg^{2+}$ over other divalent first-row transition metals. The complexes of $Hg^{2+}$ with 1 and 2 were successfully isolated. A huge enhancement in the fluorescence for both one- and two-photon excitations makes these compounds suitable candidates to be used for fluorescent labeling of biological systems.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4280-4280
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• 2012

• Journal of Environmental Science International
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• v.24 no.7
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• pp.955-960
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• 2015

A colorimetric chemosensors $Sn^{2+}$ have been designed and synthesized by three steps. The spirolactam ring-opening process of rhodamine B is one of the most useful mechanisms for controlling fluorescence properties. Herein, new fluorescent chemosensors 1 and 2 based on rhodamine B containing phenothiazine derivertive were synthesized. They exhibit selective fluorescence enhancement behaviour in the presence of $Sn^{2+}$ ion. Complexation between these compounds and the metal cations were confirmed through continuous variation method. It is observed that compounds 1, 2, and $Sn^{2+}$ ion are complexed by 1:1 formation. Especially the proposed compounds 1 and 2 exhibit quick, simple and facile synthetic route.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2009.03a
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• pp.162-163
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• 2009

Colorimetric chemosensors are now considered as one of the most effective analytical method used in the environmental monitoring. In this study, 10 new direct dyes were synthesized to be used as colorimetric chemosensor. When metal ions such as $Al^{3+},\;Ca^{2+},\;Cd^{2+},\;Cr^{3+},\;Cu^{2+},\;Fe^{2+},\;Fe^{3+},\;Hg{^2+},\;Li^+,\;Mg^{2+},\;Na^+,\;Ni^{2+},\;Pb^{2+}\;and\;Zn^{2+}$ were added to the solutions of new dyes, the colors of the solutions were changed and can be easily detected by eyes without any expensive equipments. Some metal ions were coordinated to the new direct dyes forming complex. The experimental data and conclusions were rationalized by UV-VIS spectroscopy.

• Textile Coloration and Finishing
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• v.26 no.1
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• pp.7-12
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• 2014

Nowdays, fluorescent rhodamine chemosensors have attracted a worldwide interest due to its ability to selectively detect heavy and transition metal cations. Due to the importance in environmental and biological toxic effects, the developments of fluorescent chemosensors have been received considerable attention in recent. Especially, a rhodamine-based chemosensor probes have been proved to be useful by exhibiting the efficient "off-on" fluorescence switching toward selected metal cations. This fluorophore can undergo the transformation from non-fluorescent and colorless spirolactam derivative to fluorescent ring-open form. In this study, a new fluorescent chemosensor was synthesized using rhodamine B through two-step procedures, and its selectivity and related optical property were characterized. Selectivity and sensitivity was found toward $Cu^{2+}$ guest molecules and then related optical properties of rhodamine B based fluorescent chemosensor compound were characterized using discussed. In addition, computational calculation was used to determine the HOMO/LUMO values.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1173-1176
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• 2009