Browsing by Author "Sung, Yi-Ming"

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An NAD(P)H: quinone oxidoreductase 1 (NQO1) enzyme responsive nanocarrier based on mesoporous silica nanoparticles for tumor targeted drug delivery in vitro and in vivo
(2016)
Gayam, Srivardhan Reddy
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Venkatesan, Parthiban
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Sung, Yi-Ming
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Sung, Shuo-Yuan
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Hu, Shang-Hsiu
The synthesis and characterization of an NAD(P)H: quinone oxidoreductase 1 (NQO1) enzyme responsive nanocarrier based on mesoporous silica nanoparticles (MSNPs) for on-command delivery applications has been described in this paper. Gatekeeping of MSNPs is achieved by the integration of mechanically interlocked rotaxane nanovalves on the surface of MSNPs. The rotaxane nanovalve system is composed of a linear stalk anchoring on the surface of MSNPs, an alpha-cyclodextrin ring that encircles it and locks the payload "cargo" molecules in the mesopores, and a benzoquinone stopper incorporated at the end of the stalk. The gate opening and controlled release of the cargo are triggered by cleavage of the benzoquinone stopper using an endogenous NQO1 enzyme. In addition to having efficient drug loading and controlled release mechanisms, this smart biocompatible carrier system showed obvious uptake and consequent release of the drug in tumor cells, could selectively induce the tumor cell death and enhance the capability of inhibition of tumor growth in vivo. The controlled drug delivery system demonstrated its use as a potential theranostic material.
Colorimetric detection of Al3+ ions using triazole-ether functionalized gold nanoparticles
(2013-12-15)
Chen, Yu-Ching
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Lee, I-Lin
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Sung, Yi-Ming
;
Wu, Shu-Pao
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應用化學系
A sensitive, selective colorimetric Al3+ detection method has been developed by using triazole-ether functionalized gold nanoparticles (TTP-AuNPs). Gold nanoparticles were prepared by reducing HAuCl4 with sodium borohydride in the presence of 5-(1,2-dithiolan-3-yl)-N-(prop-2-yn-1-yl)pentanamide (TP). The azide part of 2-[2-(2-azidoethoxy)ethoxy]ethanol and the acetylene part of TP were combined to form a triazole structure through a click reaction. Aggregation of TTP-AuNPs was induced immediately in the presence of Al3+ ions, yielding a color change from red to blue. This Al3+-induced aggregation of TTP-AuNPs was monitored first with the naked eye and then UV-vis spectroscopy with a detection limit of 18.0 nM. The TTP-AuNPs showed excellent selectivity for Al3+, compared to other metal ions (Ag+, Ca2+, Cd2+, Co2+, Cu2+, Cr3+, Fe2+, Fe3+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+). In addition, TTP-AuNPs were used to detect Al3+ in sea water samples, with low interference. (C) 2013 Elsevier B.V. All rights reserved.
Colorimetric detection of Cd(II) ions based on di-(1H-pyrrol-2-yl)methanethione functionalized gold nanoparticles
(2014-10-01)
Sung, Yi-Ming
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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 sensitive and selective colorimetric Cd2+ detection method was developed using di-(1H-pyrrol-2-yl)methanethione functionalized gold nanoparticles (DP-AuNPs). Aggregation of DP-AuNPs was induced immediately in the presence of Cd2+, yielding a color change from red to blue. This Cd2+-induced aggregation of DP-AuNPs was monitored using the naked eye and UV-vis spectroscopy. The SPR absorbance( 635 nm) of the reaction between DP-AuNPs and Cd2+ shows a good linearity in the Cd2+ concentration range of 0.5-16 mu M and a low detection limit 16.6 nM (S/N = 3). The DP-AuNPs showed excellent selectivity toward Cd2+ compared to other metal ions Ag+, Al3+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+. Optimal detection of Cd2+ was achieved over a pH range from 4 to 9.5. Furthermore, DP-AuNPs were applied to detect Cd2+ in lake water, showing low interference. (C) 2014 Elsevier B.V. All rights reserved.
Colorimetric detection of Cd(II) ions based on di-(1H-pyrrol-2-yl)methanethione functionalized gold nanoparticles
(2014-10-01)
Sung, Yi-Ming
;
Wu, Shu-Pao
;
應用化學系
;
Department of Applied Chemistry
A sensitive and selective colorimetric Cd2+ detection method was developed using di-(1H-pyrrol-2-yl)methanethione functionalized gold nanoparticles (DP-AuNPs). Aggregation of DP-AuNPs was induced immediately in the presence of Cd2+, yielding a color change from red to blue. This Cd2+-induced aggregation of DP-AuNPs was monitored using the naked eye and UV-vis spectroscopy. The SPR absorbance( 635 nm) of the reaction between DP-AuNPs and Cd2+ shows a good linearity in the Cd2+ concentration range of 0.5-16 mu M and a low detection limit 16.6 nM (S/N = 3). The DP-AuNPs showed excellent selectivity toward Cd2+ compared to other metal ions Ag+, Al3+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe2+, Fe3+, Hg2+, Mg2+, Mn2+, Ni2+, Pb2+, and Zn2+. Optimal detection of Cd2+ was achieved over a pH range from 4 to 9.5. Furthermore, DP-AuNPs were applied to detect Cd2+ in lake water, showing low interference. (C) 2014 Elsevier B.V. All rights reserved.
Colorimetric detection of Fe(3+) ions using pyrophosphate functionalized gold nanoparticles
(2011-01-01)
Wu, Shu-Pao
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Chen, Yi-Pu
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Sung, Yi-Ming
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應用化學系
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Department of Applied Chemistry
A sensitive, selective colorimetric Fe(3+) detection method has been developed by using pyrophosphate functionalized gold nanoparticles (P(2)O(7)(4-)-AuNPs). Gold nanoparticles were prepared by reducing HAuCl(4) with sodium borohydride, in the presence of Na(4)P(2)O(7). IR spectra suggested that pyrophosphates were capped on the surface of the gold nanoparticles. Aggregation of P(2)O(7)(4-)-AuNPs was induced immediately in the presence of Fe(3+) ions, yielding a color change from pink to violet. This Fe(3+)-induced aggregation of P(2)O(7)(4-)-AuNPs was monitored using first the naked eye and then UV-vis spectroscopy with a detection limit of 5.6 mu M. The P(2)O(7)(4-)-AuNPs bound by Fe(3+) showed excellent selectivity compared to other metal ions (Ca(2+), Cd(2+), Co(2+), Fe(2+), Hg(2+), K(+), Mg(2+), Mn(2+), Na(+), Ni(2+), Pb(2+), and Zn(2+)). The best detection of Fe(3+) was achieved in a pH range from 3 to 9. In addition, the P(2)O(7)(4-)-AuNPs were also used to detect Fe(3+) in lake water samples, with low interference.
Colorimetric detection of Fe3+ ions using pyrophosphate functionalized gold nanoparticles
(2011-01-01)
Wu, Shu-Pao
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Chen, Yi-Pu
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Sung, Yi-Ming
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應用化學系
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Department of Applied Chemistry
A sensitive, selective colorimetric Fe3+ detection method has been developed by using pyrophosphate functionalized gold nanoparticles (P2O74--AuNPs). Gold nanoparticles were prepared by reducing HAuCl4 with sodium borohydride, in the presence of Na4P2O7. IR spectra suggested that pyrophosphates were capped on the surface of the gold nanoparticles. Aggregation of P2O74--AuNPs was induced immediately in the presence of Fe3+ ions, yielding a color change from pink to violet. This Fe3+-induced aggregation of P2O74--AuNPs was monitored using first the naked eye and then UV-vis spectroscopy with a detection limit of 5.6 mu M. The P2O74--AuNPs bound by Fe3+ showed excellent selectivity compared to other metal ions (Ca2+, Cd2+, Co2+, Fe2+, Hg2+, K+, Mg2+, Mn2+, Na+, Ni2+, Pb2+, and Zn2+). The best detection of Fe3+ was achieved in a pH range from 3 to 9. In addition, the P2O74--AuNPs were also used to detect Fe3+ in lake water samples, with low interference.
Colorimetric sensing of Cu(II): Cu(II) induced deprotonation of an amide responsible for color changes
(2010)
Wu, Shu-Pao
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Du, Kun-Ju
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Sung, Yi-Ming
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應用化學系
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Department of Applied Chemistry
9,10-Anthraquinone-based chemosensor 1 indicates the presence of Cu(II) ions among other transition metal ions with high selectivity by a color change from yellow to dark red. Chemosensor 2 shows binding toward Cu(II), Ni(II) and Co(II) with color changes from yellow to dark red, red and pale green, respectively. Especially, Co(II) binding with chemosensor 2 causes significantly green fluorescence. On addition of Cu(II), 1 and 2 exhibit 76 and 80 nm red shifts in absorption wavelength (pH 7.0). The effect on pH by the formation of these 1-Cu(II) and 2-Cu(II) complexes was determined by UV-vis spectroscopic pH titration. In the pH range of 6-7.5, a maximum absorption was observed at 473 nm and exhibited the formation of deprotonated 1-Cu(II) and 2-Cu(II) complexes.
Colorimetric sensing of iodide based on triazole-acetamide functionalized gold nanoparticles
(2014-04-01)
Lee, I-Lin
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Sung, Yi-Ming
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Wu, Chien-Hou
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Wu, Shu-Pao
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應用化學系
We have modified gold nanoparticles (AuNPs) with triazole acetamide to obtain a material for the sensitive and selective colorimetric determination of iodide. The functionalized AuNPs were prepared by a reductive single chemical step using a Cu(I)-catalyzed click reaction. The presence of iodide ions induces the aggregation of these AuNPs and results in a color change from wine-red to purple. The iodide-induced aggregation can be detected visually with bare eyes, but also by photometry. The detection limit is as low as 15 nM. The method displays excellent selectivity for iodide over other anions due to the selective interaction with the amido groups of the triazole. The method was applied to the determination of iodide in spiked lake waters.
Highly fluorescent probe for copper (II) ion based on commercially available compounds and live cell imaging
(2014-07-01)
Udhayakumari, Duraisamy
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Velmathi, Sivan
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Sung, Yi-Ming
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Wu, Shu-Pao
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應用化學系
The commercially available 2, 3-diaminophenazine, 1,2-diamino-anthraquinone and 2, 4-dinitrophenylhydrazine (S1-S3) act as a colorimetric, fluorescent probes for selective detection of Cu2+ ions in aqueous medium over other metal ions. In presence of Cu2+, S1 shows fluorescent turn-on due to the inhibition of photoinduced electron transfer mechanism. The fluorescent probes S1-S3 detect Cu2+ ions in aqueous solution at nanomolar levels. Theoretical calculations were emploued to understand the sensing mechanism of the semsors towards Cu2+. S1, S2 and S3 were further applied for biological imaging to confirm that it can be used as a fluorescent probe for monitoring Cu2+ in living cells, and demonstrated its value in practical applications such as environmental and biological systems. (C) 2014 Elsevier B.V. All rights reserved.
Highly selective and sensitive colorimetric detection of Ag(I) using N-1-(2-mercaptoethyl)adenine functionalized gold nanoparticles
(2014-07-01)
Sung, Yi-Ming
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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 sensitive and selective colorimetric Ag+ detection method was developed by using N-1-(2-mercaptoethyl)adenine functionalized gold nanoparticles (MEA-AuNPs). The presence of Ag+ immediately induced aggregation of MEA-AuNPs, yielding a color change from red to blue. This Ag+-induced aggregation of MEA-AuNPs was monitored by bare eye and UV-vis spectroscopy with a detection limit of 3.3 nM. MEA-AuNPs showed excellent selectivity toward Ag+ compared with other metal ions through interaction between adenine and Ag+. The best detection of Ag+ was achieved at pH 6-9. Furthermore, MEA-AuNPs were applied to detect Ag+ in lake water with low interference. (C) 2014 Elsevier B.V. All rights reserved.
Quinone-Modified Mn-Doped ZnS Quantum Dots for Room-Temperature Phosphorescence Sensing of Human Cancer Cells That Overexpress NQO1
(2015-11-25)
Sung, Yi-Ming
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Gayam, Srivardhan Reddy
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Hsieh, Pei-Ying
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Hsu, Hsin-Yun
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Diau, Eric Wei-Guang
Early detection of cancer cells in a rapid and sensitive approach is one of the great challenges in modern clinical cancer care. This study has demonstrated the first example of a rapid, selective, and sensitive phosphorescence probe based on phosphorescence energy transfer (PET) for cancer-associated human NAD(P)H:quinone oxidoreductase isozyme 1 (NQO1). An efficient room-temperature phosphorescence NQO1 probe was constructed by using Mn-doped ZnS quantum dots (Mn:ZnS QDs) as donors and trimethylquinone propionic acids as acceptors. Phosphorescence quenching of Mn:ZnS QDs from the Mn:ZnS QDs to a covalently bonded quinone was achieved through PET. Phosphorescence of Mn:ZnS QDs was turned on by the rapid reduction-initiated removal of the quinone quencher by NQO1. This probe shows low cellular toxicity and can rapidly distinguish between NQO1-expressing and -nonexpressing cancer cell lines through phosphorescence imaging.
The Oxidation of Phenylhydrazine by Tyrosinase
(2013-04-01)
Sung, Yi-Ming
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Gayam, Srivardhan Reddy
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Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
Tyrosinase was found to catalyze the oxidation of phenylhydrazine to phenol in a reaction that did not resemble those typically performed by tyrosinase. The kinetics of this reaction was investigated by measuring the initial velocity of the formation of phenol (25 A degrees C). The values of k (cat) and K (M) for the oxidation of phenylhydrazine were obtained as 11.0 s(-1) and 0.30 mM, respectively. The generation of superoxides during the oxidation of phenylhydrazine by tyrosinase was monitored by nitroblue tetrazolium (NBT) assay. In the phenylhydrazine-tyrosinase reaction, 1 mol O-2 was required for the production of 1 mol phenol and 1/6 mol superoxide. The decomposition of superoxide by superoxide dismutase enhanced the rate constant of the oxidation of phenylhydrazine. Phenol formed in the oxidation of phenylhydrazine by tyrosinase was further oxidized by tyrosinase to an o-quinone, after the oxidation of phenylhydrazine by tyrosinase was almost completed.
Triazole functionalized gold nanoparticles for colorimetric Cr+ sensing
(2013-11-01)
Chen, Yu-Ching
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Lee, I-Lin
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Sung, Yi-Ming
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Wu, Shu-Pao
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應用化學系
Triazole functionalized gold nanoparticles (NTP@AuNPs) were synthesized through a click reaction and have been developed for sensitive and selective colorimetric Cr3+ detection. Gold nanoparticles were prepared by reducing HAuCl4 with sodium citrate and then using 4-(prop-2-ynyloxy)pyridine (PP) as the capping agent. The acetylene part of PP and the azide part of 1-(azidomethyl)-4-nitrobenzene were combined to form a triazole structure through a click reaction. Aggregation of NTP@AuNPs was induced immediately in the presence of Cr3+ ions, yielding a color change from red to purple. This Cr3+-induced aggregation of NTP@AuNPs was first monitored using the naked eye and then UV-vis spectroscopy with a detection limit of 1.4 mu M. In addition, NTP@AuNPs were also used to detect Cr3+ in lake water samples, with low interference. (C) 2013 Elsevier B.V. All rights reserved.
Triazole-acetate functionalized gold nanoparticles for colorimetric Pb(II) sensing
(2014)
Lee, I-Lin
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Sung, Yi-Ming
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Wu, Shu-Pao
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應用化學系
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Department of Applied Chemistry
New triazole-acetate functionalized gold nanoparticles (TTA-AuNPs) for sensitive and selective colorimetric detection of Pb2+ were developed. Aggregation of TTA-AuNPs was induced immediately in the presence of Pb2+, yielding a color change from wine-red to purple. This Pb2+-induced aggregation of TTA-AuNPs was monitored by the bare eye and UV-vis spectroscopy with a detection limit of 16.7 nM. TTA-AuNPs showed excellent selectivity toward Pb2+ compared to other metal ions through the interaction between the carboxyl group and triazole structure of TTA and Pb2+. The best detection of Pb2+ was achieved in a pH range from 5 to 10. Furthermore, TTA-AuNPs were applied to detect Pb2+ in lake water with low interference.