Browsing by Author "Chen, Wei-Chieh"

Now showing 1 - 5 of 5

A coumarin-based sensitive and selective fluorescent sensor for copper(II) ions
(2014-09-01)
Yeh, Jiun-Ting
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Chen, Wei-Chieh
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Liu, Shi-Rong
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Wu, Shu-Pao
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應用化學系
A new coumarin-derived fluorescent probe (1) exhibited significant fluorescence quenching in the presence of Cu2+ ions. Other metal ions, e.g. Ag+, Ca2+, Cd2+, Co2+, Fe2+, Fe3+, Hg2+, K+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+, produced only minor changes in the fluorescence of chemosensor 1. The binding ratio of the chemosensor-Cu2+ complexes was found to be 2 :1, according to Job plot experiments. The association constant (K-a) for Cu2+ binding with chemosensor 1 was found to be 9.56 x 10(9) M-2. The maximum fluorescence quenching caused by Cu2+ binding with chemosensor 1 occurred over a pH range of 5-9. Moreover, fluorescence microscopy experiments showed that chemosensor 1 could be used as a fluorescent probe for detecting Cu2+ in living cells.
A dual-mode chemosensor: Highly selective colorimetric fluorescent probe for Cu2+ and F- ions
(2014-12-01)
Udhayakumari, Duraisamy
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Velmathi, Sivan
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Chen, Wei-Chieh
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Wu, Shu-Pao
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應用化學系
N-Phenylthiosemicarbazones (R1-R4) have been synthesized and characterized by various spectroscopic techniques. The sensors (R1-R4) exhibited highly selective and sensitive recognition toward Cu2+ and F ions over other cations and anions via visual color change. Sensors showed a significant fluorescent enhancement toward Cu2+ in aqueous medium and found a sub-nanomolar detection limit with good quantum yield. R1 displayed high selectivity to Cu2+ over other interference ions with 89-fold fluorescence intensity enhancement upon the addition of 2 equiv. of Cu2+. In addition, the turn-on fluorescent changes upon the addition of Cu2+, is also applied in cell imaging. (C) 2014 Elsevier B.V. All rights reserved.
A highly selective turn-on fluorescent probe for hypochlorous acid based on hypochlorous acid-induced oxidative intramolecular cyclization of boron dipyrromethene-hydrazone
(2015-07-02)
Chen, Wei-Chieh
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Venkatesan, Parthiban
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Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
A BODIPY-based fluorescent probe, HBP, was developed for the detection of hypochlorous acid based on the specific hypochlorous acid-promoted oxidative intramolecular cyclization of heterocyclic hydrazone in response to the amount of HOCl. The reaction is accompanied by a 41-fold increase in the fluorescent quantum yield (from 0.004 to 0.164). The fluorescence intensity of the reaction between HOCl and HBP is linear in the HOCl concentration range of 1-8 mu M with a detection limit of 2.4 nM (S/N = 3). Confocal fluorescence microscopy imaging using RAW264.7 cells showed that the new probe HBP could be used as an effective fluorescent probe for detecting HOCl in living cells. (C) 2015 Elsevier B.V. All rights reserved.
A hypochlorous acid turn-on fluorescent probe based on HOCl-promoted oxime oxidation and its application in cell imaging
(2014-06-01)
Yu, Shiang-Yi
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Hsu, Chen-Yi
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Chen, Wei-Chieh
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Wei, Ling-Fang
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Wu, Shu-Pao
A coumarin-based fluorometric probe, HS1, has been successfully developed for highly sensitive and selective detection of hypochlorous acid (HOCl). The probe is based on the specific HOCl-promoted oxidation of oxime. The reaction is accompanied by a 7-fold increase in the fluorescent quantum yield (from 0.03 to 0.21). The fluorescence intensity of the reaction between HOCl and HS1 shows a good linearity in the HOCl concentration range of 1-20 mu M and a low detection limit of 25 nM (S/N = 3). In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the HS1 probe could be an efficient fluorescent probe for HOCl in living cells. (C) 2014 Elsevier B.V. All rights reserved.
A turn-on fluorescent probe for hypochlorous acid based on HOCl-promoted removal of the C=N bond in BODIPY-hydrazone
(2015-01-01)
Chen, Wei-Chieh
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Venkatesan, Parthiban
;
Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
A boron dipyrromethene-based fluorescent probe, BODH, has been successfully developed for hypochlorous acid detection based on the HOCl-promoted oxidative removal of the C=N bond in response to the amount of HOCl. The reaction is accompanied by a 6-fold increase in fluorescent quantum yield (from 0.05 to 0.29). The fluorescence intensity of the reaction between HOCl and BODH shows a good linearity in the HOCl concentration range of 1-25 mu M with a low detection limit of 205 nM (S/N = 3). Confocal fluorescence microscopy imaging using RAW264.7 cells shows that the new probe, BODH, can be used as an effective fluorescent probe for the detection of HOCl in living cells.