Browsing by Author "Wu, Shu-Pao"

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A BODIPY-based colorimetric and fluorometric chemosensor for Hg(II) ions and its application to living cell imaging
(2012)
Vedamalai, Mani
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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 new monostyryl boron dipyrromethene derivative (MS1) appended with two triazole units indicates the presence of Hg2+ among other metal ions with high selectivity by color change and red emission. Upon Hg2+ binding, the absorption band of MS1 is blue-shifted by 29 nm due to the inhibition of the intramolecular charge transfer from the nitrogen to the BODIPY, resulting in a color change from blue to purple. Significant fluorescence enhancement is observed with MS1 in the presence of Hg2+; the metal ions Ag+, Ca2+, Cd2+, Co2+, Cu2+, Fe2+, Fe3+, K+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ cause only minor changes in the fluorescence of the system. The apparent association constant (K-a) of Hg2+ binding in MS1 is found to be 1.864 x 10(5) M-1. In addition, fluorescence microscopy experiments show that MS1 can be used as a fluorescent probe for detecting Hg2+ in living cells.
A BODIPY-Based Highly Selective Fluorescent Chemosensor for Hg2+ Ions and Its Application in Living Cell Imaging
(2012-02-01)
Vedamalai, Mani
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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 new borondipyrromethene (BODIPY) derivative (FS1) containing two triazole units exhibits an enhanced fluorescence in the presence of Hg2+ ions and a high selectivity for Hg2+ ions over competing metal ions in methanol: Ag+, Ca2+, Cd2+, Co2+, Cu2+, Fe2+, Fe3+, K+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence of FS1. The apparent dissociation constant (Kd) of FS1Hg2+ was found to be 62 mu M. Moreover, fluorescence microscopy experiments showed that FS1 can be used as a fluorescent probe for detecting Hg2+ ions in living cells.
A coumarin-based fluorescent probe for thiols and its application in cell imaging
(2016-09)
Liao, Yu-Cheng
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Venkatesan, Parthiban
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Wei, Ling-Fang
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Wu, Shu-Pao
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應用化學系
A new coumarin-based fluorescent probe CAA containing an acrylamide group has been designed and synthesized for the detection of biothiols. The probe CAA shows high selectivity and sensitivity for cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) over other amino acids. A fluorescence turn-on response is induced by a Michael-type reaction. It shows a highly sensitive fluorescence emission to Cys, Hcy, and GSH, with detection limits of 192 nM for Cys, 158 nM for Hcy, and 155 nM for GSH (S/N = 3). Furthermore, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that CAA can be an effective fluorescent probe for thiols in living cells. (C) 2016 Elsevier B.V. All rights reserved.
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 far-red to NIR emitting ultra-sensitive probe for the detection of endogenous HOCl in zebrafish and the RAW 264.7 cell line
(2019-04-14)
Natarajan, Vijay
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Thirumalaivasan, Natesan
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Wu, Shu-Pao
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Sivan, Velmathi
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應用化學系
Fluorescence imaging is a dynamic tool for monitoring the functions of biomolecules in living systems. Probes with emission in the far-red to near-infrared range have been found to demonstrate great application prospects in bioimaging due to their deep tissue penetration, low background fluorescence, minimum photodamage to the tissue and high sensitivity. The present study aimed to construct a far-red to near-infrared emitting probe (PI) bearing dicyanoisophorone coupled with a phenothiazine moiety. The probe exhibits an instant response towards HOCl with a colour change from red to yellow with a 100 fold fluorescence enhancement at 620 nm with a low detection limit (42 nM). The electron-rich sulfur atom can be oxidised by HOCl; this endows the probe with distinct selectivity over other anions as well as other reactive oxygen species. The probe demonstrates great cell permeability with low toxicity to the cell. Therefore, the probe can be effectively applied in biological systems to monitor the endogenous level of HOCl produced by PMA in living systems and in the fluorescence imaging of endogenous HOCl in zebrafish and the RAW 264.7 cell line.
A fluorescence turn-on probe for cysteine and homocysteine based on thiol-triggered benzothiazolidine ring formation
(2014-11-07)
Liu, Shi-Rong
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Chang, Chao-Yiu
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Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
We synthesized a new coumarin-based probe TP, containing a disulfide moiety, to detect biothiols in cells. A fluorescence turn-on response is induced by the thiol-disulfide exchange of the probe, with subsequent intramolecular benzothiazolidine ring formation giving rise to a fluorescent product. The probe exhibits an excellent selectivity for cysteine (Cys) and homocysteine (Hcy) over glutathione (GSH) and other amino acids. The fluorescent probe also exhibits a highly sensitive fluorescence turn-on response to Cys and Hcy with detection limits of 0.8 mu M for Cys and 0.5 mu M for Hcy. In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the probe TP could be an efficient fluorescent detector for thiols in living cells. (C) 2014 Elsevier B.V. All rights reserved.
A fluorescent turn-on probe for detection of hypochlorus acid and its bioimaging in living cells
(2020-06-05)
Chu, Chien-Ju
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Wu, Guan-Syuan
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Ma, Ho-I
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Venkatesan, Parthiban
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Thirumalaivasan, Natesan
Hypochlorous acid has played several functions in the biological system. However, excess HOCI can cause damage to biomolecules and result in some diseases. Accordingly, a new fluorescent probe, BSP, has been developed for fast recognition of HOCI through the HOG-induced oxidation of methyl phenyl sulfide to sulfoxide. The reaction of BSP with HOG caused a 22-fold fluorescence enhancement (quantum yield increase from 0.006 to 0.133). The detection limit of HOCI is found to be 30 nM (S/N = 3). The fluorescence enhancement is due to the suppression of the photo-induced electron transfer from the methyl phenyl sulfide moiety to BODIPY. Eventually, the cellular fluorescence imaging experiment showed that BSP could be effectively used for monitoring HOCI in living cells. (C) 2020 Elsevier B.V. All rights reserved.
A fluorescent turn-on probe for Hg(II) based on an NTe2 chelating motif and its application in living cell imaging
(2015-06-01)
Kao, Shao-Lun
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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 boron dipyrromethene (BODIPY) derivative (BODTe) with an NTe2 chelating motif exhibits high selectivity for Hg2+ detection. Significant fluorescence enhancement was observed with the chemosensor BODTe in the presence of Hg2+. However, the metal ions Ag+, Al3+, Ca2+, Cd2+, Co2+, Cu2+,Cr3+, Fe2+, Fe3+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence values of the system. The association constant (Ka) of Hg2+ binding for the chemosensor BODTe was found to be 3.84 x 10(3) M-1, with a detection limit of 19.2 mu M. The maximum fluorescence enhancement caused by Hg2+ binding in the chemosensor BODTe was observed over the pH range of 4.0-10.0. Confocal fluorescence microscopy imaging using RAW 264.7 cells showed that BODTe can be used as an effective fluorescent probe for detecting Hg2+ in living cells. (C) 2015 Elsevier B.V. All rights reserved.
A highly fluorescent zinc complex of a dipodal N-acyl hydrazone as a selective sensor for H2PO4- ions and application in living cells
(2015-01-01)
Suganya, Sivalingam
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Velmathi, Sivan
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Venkatesan, Parthiban
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Wu, Shu-Pao
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Boobalan, Maria Susai
A dipodal N-acyl hydrazone receptor (R1) was synthesized in a single step, and utilized as a test probe for the selective sensing of metal ions as well as anions. Upon the exposure to various metal ions, R1 displays rapid colorimetric and absorption changes in the presence of Co2+, Ni2+, Cu2+ and Zn2+ ions. However, R1 shows a selective fluorescence response only in the presence of Zn2+ ions and no other metal ions showed obvious changes. In particular, zinc acetate showed higher sensitivity over other zinc sources. Upon the binding of Zn2+ ions with R1, the colorless solution changed into fluorescent yellow color accompanied by the conversion of the non-fluorescence nature into the highly fluorescence nature. The in situ formed R1-Zn2+ complex was further explored for the reversible recognition of H2PO4- ions selectively over other anions such as F-, Cl-, Br-, AcO-, CN-, HSO4- and NO3- ions. A strong and enhanced emission at 502 nm and 534 nm corresponding to the R1-Zn2+ complex was quenched completely in the presence of H2PO4- ions. Relay recognition of different phosphates such as mono, di and tri basic phosphate ions was also tested. Furthermore, R1 has good cell permeability and could serve as a bioprobe in living cells for the intracellular uptake of Zn2+ and H2PO4- ions. Time dependent density functional (TDDFT) calculation has been performed to demonstrate the binding of Zn2+ ions with R1.
A highly selective fluorescent anthracene-based chemosensor for imaging Zn2+ in living cells and zebrafish
(2020-05-01)
Minh-Hai Nguyen
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Thi-Nguyet Nguyen
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Danh-Quang Do
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Hung-Huy Nguyen
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Quan-Manh Phung
A new fluorescent chemosensor (An3) bearing anthracenyl rings was designed and developed for detection of Zn2+. Addition of Zn2+ into An3 gave rise to a fluorescent turn-on response at 424 nm whereas Al3+, Cd (2+), Co2+, Cu2+, K+, Mg2+, Zn2+, Ca2+, Fe3+, Mn2+, Ni2+, Pb2+, and Hg2+ did not induce any emission intensity enhancement. Furthermore, the probe exhibited high selectivity toward Zn2+ and a very low detection limit (36 nM) based on chelation-enhanced fluorescence. Theoretical calculations revealed the possible formation of 1:1 and 1:2 complexes between An3 and Zn2+. In bioimaging experiments, the chemosensor displayed low cytotoxicity and good biocompatibility, rendering it an effective tool for fluorescent visualization of Zn2+ in living cells and zebrafish models.
A highly selective fluorescent sensor for Hg(II) based on an NTe2 chelating motif and its application to living cell imaging
(2015-01-01)
Kao, Shao-Lun
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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 fluorescent probe (NBDTe) based on an NTe2 chelating motif has been developed for the highly selective and sensitive detection of Hg2+. Significant fluorescence enhancement was observed with the chemosensor NBDTe in the presence of Hg2+. Moreover, the metal ions Ag+, Al3+, Ca2+, Cd2+, Co2+, Cu2+, Cr3+, Fe2+, Fe3+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence values of the system. The association constant (K-a) of Hg2+ binding to the chemosensor NBDTe was found to be 3.81 x 10(3) M (1), with a detection limit of 4.2 mu M. The maximum fluorescence enhancement caused by Hg2+ binding to the chemosensor NBDTe was observed over the pH range of 4.0-10.0. In addition, fluorescence microscopy experiments showed that the chemosensor NBDTe can be used as a fluorescent probe for detecting Hg2+ in living cells.
A highly selective turn-on fluorescence chemosensor for Hg(II) and its application in living cell imaging
(2014-10-01)
Yu, Shiang-Yi
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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 new coumarin derivative (MS1) containing an imine moiety and a hydroxyl moiety exhibits an enhanced fluorescence in the presence of Hg2+ ions. Other metal ions Al3+, Ca2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg-2+,Hg- Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence values of MS1. The binding ratio of MS1-Hg2+ complexes was determined from the Job plot to be 1:1. The binding constant (Ka) of Hg2+ binding to MS1 was found to be 6.85 x 103 M-1. The maximum fluorescence enhancement caused by Hg2+ binding to MS1 was observed in the pH range of 6.5-9.0. Confocal fluorescence microscopy imaging using RAW 264.7 cells showed that MS1 could be used as an effective fluorescent probe for detecting Hg2+ in living cells. (C) 2014 Elsevier B.V. All rights reserved.
A highly selective turn-on fluorescence chemosensor for Hg(II) and its application in living cell imaging
(2014-10-01)
Yu, Shiang-Yi
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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 new coumarin derivative (MS1) containing an imine moiety and a hydroxyl moiety exhibits an enhanced fluorescence in the presence of Hg2+ ions. Other metal ions Al3+, Ca2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg-2+,Hg- Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence values of MS1. The binding ratio of MS1-Hg2+ complexes was determined from the Job plot to be 1:1. The binding constant (Ka) of Hg2+ binding to MS1 was found to be 6.85 x 103 M-1. The maximum fluorescence enhancement caused by Hg2+ binding to MS1 was observed in the pH range of 6.5-9.0. Confocal fluorescence microscopy imaging using RAW 264.7 cells showed that MS1 could be used as an effective fluorescent probe for detecting Hg2+ in living cells. (C) 2014 Elsevier B.V. All rights reserved.
A highly selective turn-on fluorescent chemosensor for copper(II) ion
(2010-12-18)
Wu, Shu-Pao
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Wang, Tzu-Hao
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Liu, Shi-Rong
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應用化學系
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Department of Applied Chemistry
A new pyrene derivative (1) containing a diaminomaleonitrile moiety exhibits high selectivity for Cu(2+) detection. Significant fluorescence enhancement was observed with chemosensor 1 in the presence of Cu(2+). However, the metal ions Ag(+), Ca(2+), Cd(2+), Co(2+), Fe(2+), Fe(3+), Hg(2+), Mg(2+), Mn(2+), Ni(2+), Pb(2+), and Zn(2+) produced only minor changes in fluorescence values for the system. The apparent association constant (K(a)) of Cu(2+) binding in chemosensor 1 was found to be 5.55x10(3) M(-1). The maximum fluorescence enhancement caused by Cu(2+) binding in chemosensor 1 was observed over the pH range 5-7.5. (C) 2010 Elsevier Ltd. All rights reserved.
A highly selective turn-on fluorescent chemosensor for copper(II) ion (vol 66, pg 9655, 2010)
(2011-04-01)
Wu, Shu-Pao
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Wang, Tzu-Hao
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Liu, Shi-Rong
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應用化學系
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Department of Applied Chemistry
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 highly selective turn-on fluorescent sensor for Cu(II) based on an NSe2 chelating moiety and its application in living cell imaging
(2013)
Chou, Cho-Yen
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Liu, Shi-Rong
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Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
In this study, a boron-dipyrromethene (BODIPY)-based fluorescent chemosensor CBS was developed for metal ion sensing. It was found that CBS containing an NSe2 moiety exhibited high selectivity for Cu2+ detection while CBS in the presence of Cu2+ displayed significant fluorescence enhancement. However, the metal ions Ag+, Ca2+, Co2+, Cr3+, Fe2+, Fe3+, Hg2+, K+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+ produced only minor changes in the fluorescence values of the system. The binding constant (K-a) of Cu2+ binding to CBS was found to be 7.28 x 10(3) M-1. The binding ratio of CBS-Cu2+ complexes was determined from the Job plot to be 1 : 1. The maximum fluorescence enhancement caused by Cu2+ binding to CBS was observed over the pH range 5.0-9.0. Additionally, the methyl thiazolyl tetrazolium (MTT) assay demonstrated the CBS to have low cytotoxicity. Confocal fluorescence microscopy imaging using RAW264.7 cells showed that CBS could be used as an effective fluorescent probe for detecting Cu2+ in living cells.
A highly selective turn-on fluorescent sensor for fluoride and its application in imaging of living cells
(2014-12-01)
Yeh, Jiun-Ting
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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 fluorescent probe (FS) based on a fluoride-specific desilylation reaction has been developed for a highly selective and sensitive detection of F-. In the presence of F-, the probe FS provided significant green fluorescence enhancement, while other anions produced only minor changes in fluorescence intensity. The probe FS has a limit of detection of 1.45 mu M, which is reasonable for the detection of micromolar concentrations of F- ions. The maximum fluorescence enhancement induced by F- in the probe was observed over the pH range 7-10. Moreover, fluorescence microscopy imaging using mouse leukaemic monocyte macrophage showed that the probe FS could be an efficient fluorescent probe for F- ions in living cells.
A hydrogen sulfide triggered self-immolative fluorescent probe for lysosome labeling in live cells
(2018-02-07)
Velusamy, Nithya
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Thirumalaivasan, Natesan
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Bobba, Kondapa Naidu
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Wu, Shu-Pao
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Bhuniya, Sankarprasad
We developed a naphthalimide-based, lysosome-targeting, and self-immolative fluorescent probe for H2S detection. Probe LS-1 comprises a 2-formylbenzoate derivative of the 1,8-naphthalimide fluorophore. H2S forms a thiohemiacetal intermediate by reacting with the formyl group of the 2-formylbenzoate derivative, which subsequently undergoes intramolecular cyclization with the ester moiety to generate a free naphthalimide fluorophore (FL-1). The UV-vis absorbance (lambda(abs)) value of probe LS-1 at 450 nm increased in the presence of H2S. Similarly, with increasing H2S concentrations, the emission band (lambda(em)) centered at 560 nm increased gradually. The probe was found to be highly sensitive and chemoselective towards H2S compared with other biological analytes. Probe LS-1 was nontoxic and very stable across the physiological pH range. The probe LS-1 enables the detection of intracellular endogenous H2S formation in HT29 cells in lysosomes.