Browsing by Author "Chang, Gao-Fong"

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An organic hydrogel film with micron-sized pillar array for real-time and indicator-free detection of Zn(2+)
(2011-11-01)
Chao, Yu-Chiang
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Huang, Yi-Sa
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Wang, Hsin-Ping
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Fu, Ssu-Ming
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Huang, Chien-Hao
A hydrogel sensing film for a real-time and indicator-free detection of Zn(2+) is developed by embedding a fluorescent indicator 11,16-bis( phenyl)-6,6,21,21-tetramethyl-m-benzi-6,21-porphodimethene in a hydrogel host poly(2-hydroxyethyl methacrylate). The sensing film shows high stability and selectivity to Zn(2+). The sensitivity of the sensing film is increased by fabricating a micron-sized pillar array on the surface of the sensing film to increase the surface area. For Zn(2+) concentrations of 10 (4) and 10 (3) M, the response time is 30 and 3 s, respectively. (C) 2011 Elsevier B.V. All rights reserved.
An organic hydrogel film with micron-sized pillar array for real-time and indicator-free detection of Zn2+
(2011-11-01)
Chao, Yu-Chiang
;
Huang, Yi-Sa
;
Wang, Hsin-Ping
;
Fu, Ssu-Ming
;
Huang, Chien-Hao
A hydrogel sensing film for a real-time and indicator-free detection of Zn2+ is developed by embedding a fluorescent indicator 11,16-bis( phenyl)-6,6,21,21-tetramethyl-m-benzi-6,21-porphodimethene in a hydrogel host poly(2-hydroxyethyl methacrylate). The sensing film shows high stability and selectivity to Zn2+. The sensitivity of the sensing film is increased by fabricating a micron-sized pillar array on the surface of the sensing film to increase the surface area. For Zn2+ concentrations of 10 (4) and 10 (3) M, the response time is 30 and 3 s, respectively. (C) 2011 Elsevier B.V. All rights reserved.
Effects of Core-modification on Porphyrin Sensitizers to the Efficiencies of Dye-sensitized Solar Cells
(2014-05-01)
Mane, Sandeep B.
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Luo, Liyang
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Chang, Gao-Fong
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Diau, Eric Wei-Guang
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Hung, Chen-Hsiung
To study dye-sensitized solar cells (DSSCs) with core-modified porphyrins as the sensitizing dyes, three porphyrins with an ethynyl benzoic acid as an anchoring group are prepared. The properties of free-base regular porphyrin (N4), thiaporphyrin (N3S) and oxaporphyrin (N3O) were thoroughly studied by spectroscopic methods, DFT calculations, and photovoltaic measurements. Replacing one of the porphyrinic core nitrogen atoms by oxygen or sulfur considerably changes the absorption spectra. The Soret band of the N3O and N3S observed bathochromic shifts of 3-9 nm while the Q band reaches 700 nm to the near-infrared region. The overall conversion efficiencies of the DSSCs based on these porphyrins are in the order N4 (3.66%) >> N3S (0.22%) > N3O (0.01%). The time-correlated single photon counting observed short fluorescence lifetimes for N3O adsorbed both on TiO2 and Al2O3 which explicates the poor efficiency of DSSC using N3O as the photosensitizer.
Electrospun Fibers as a Solid-State Real-Time Zinc Ion Sensor with High Sensitivity and Cell Medium Compatibility
(2013-03-25)
Syu, Jia-Hao
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Cheng, Yi-Kai
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Hong, Wun-Yan
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Wang, Hsing-Ping
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Lin, Yu-Chao
meso-2,6-Dichlorophenyltripyrrinone (TPN-Cl2), a probe molecule for zinc II ions, is dispersed in a polymer host. The red fluorescence peak at 620 nm appears when the molecule forms a complex with zinc at its center. TPN-Cl2 has a high selectivity for zinc II and tolerates many common metal ions present in the human body. The probe molecules are blended with a hydrogel polymer, poly(2-hydroxyethyl methacrylate) (poly HEMA), with 30 wt% dimethylformamide (DMF). The fiber structure with 1 m diameter is made by electrospinning in DMF solution of the probe and poly HEMA mixture. The fibrous film detects zinc ions with concentrations as low as 106 M in real-time both in water and in the commonly used cell culture liquid media Dulbecco's modified Eagle medium (DMEM) and fetal bovine serum (FBS), which contain many metal ions and proteins. The time-resolution is 5 min for 106 M and 1 min for 105 M. This sensitivity and response speed satisfy the requirements for non-invasive biomedical studies.
Hydro gel light-guiding conjunction for absorptive type multi-ions detection
(2016-10-05)
Lin, Hung-Cheng
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Yang, Sean Tsungyeh
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Ng, Sock Hoon
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Zan, Hsiao-Wen
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Meng, Hsin-Fei
We present a novel miniaturized solid state sensor produced by embedding two optical fibers in a sensing hydro gel conjunction. The conjunction is a poly (2-hydroxyethyl methacrylate) (poly HEMA) hydro gel mixed with two kinds of selective fluorescent probes. Meso-2,6-Dichlorophenyltripyrrinone (TPN-Cl2) is used to react with zinc ion (Zn2+) and the synthesized "Chemosensor 1" is used to detect ferric ion (Fe3+). This hydro gel conjunction can serve as a light-guiding waveguide that allows light signals to transfer between two fibers. By using a multi-wavelength excitation light, a mixed solution that contains Zn2+ and Fe3+ can be detected in real-time. This miniaturized sensor develops an image for real-time monitoring of Zn2+ and Fe3+ ions in vivo. (C) 2016 Elsevier B.V. All rights reserved.
Integrated semiconductor optoelectronic devices for real-time and indicator-free detection of aqueous nitric oxide
(2011-05-01)
Chao, Yu-Chiang
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Yeh, Shih-De
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Zan, Hsiao-Wen
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Chang, Gao-Fong
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Meng, Hsin-Fei
A real-time and indicator-free sensor specific to nitric oxide (NO) is realized for the first time by integrating a sensing hydrogel film, a top-emitting polymer light-emitting diode (PLED), and a silicon photodetector. The top-emitting PLED is utilized to excite the sensing film specific to NO, and the photoluminescence of the sensing film is transformed into electric signal by the photodetector. The influence of the excitation light on the out-put photocurrent of the photodetector is diminished by two delicately selected organic filters based on their absorption spectra. Lead phthalocyanine is deposited on a top-emitting PLED as a filter for generating an excitation light without overlapping the emission maximum of the sensing hydrogel film. Poly(3-hexylthiophene) is placed in front of the photodetector as another filter to remove the excitation light. This sensor demonstrated a fast photocurrent response to NO with response time within 5 min. (C) 2011 Elsevier B.V. All rights reserved.
Integrated semiconductor optoelectronic devices for real-time and indicator-free detection of aqueous nitric oxide
(2011-01-01)
Wang, Shin-Ping
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Cheng, Yi-Kai
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Chao, Yu-Chiang
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Zan, Hsiao-Wen
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Chang, Gao-Fong
Sensing films specific to nitric oxide and zinc were fabricated by embedding respectively indicator 1,2-diaminoanthraquinone (DAQ) and 11,16-Bis(phenyl)-6,6,21,21-tetramethyl-m-benzi-6,21-porphodimethene (BPDM-H) in hydrogel host poly(2-hydroxyethyl methacrylate). The sensing film contains DAQ, which responses to nitric oxide, shows stability in acid environment. The sensing film contains BPDM-H responses to zinc. The electrospinning technique was also utilized to fabricate the fibrous film.
m-Benziporphodimethene: a new porphyrin analogue fluorescence zinc(II) sensor
(2008)
Hung, Chen-Hsiung
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Chang, Gao-Fong
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Kumar, Anil
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Lin, Geng-Fong
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Luo, Li-Yang
m-Benziporphodimethene is presented here as a long-wavelength Zn2+ specific chemosensor; this sensor shows fluorescence switch-on upon Zn2+ binding with no apparent background fluorescence.
New Dual Donor-Acceptor (2D--2A) Porphyrin Sensitizers for Stable and Cost-Effective Dye-Sensitized Solar Cells
(2013-09-01)
Ambre, Ram B.
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Chang, Gao-Fong
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Zanwar, Manoj R.
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Yao, Ching-Fa
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Diau, Eric Wei-Guang
A series of porphyrin sensitizers that featured two electron-donating groups and dual anchoring groups that were connected through a porphine -bridging unit have been synthesized and successfully applied in dye-sensitized solar cells (DSSCs). The presence of electron-donating groups had a significant influence on their spectroscopic, electrochemical, and photovoltaic properties. Overall, the dual anchoring groups gave tunable electronic properties and stronger attachment to TiO2. These new dyes were readily synthesized in a minimum number of steps in gram-scale quantities. Optical and electrochemical data confirmed the advantages of these dyes for use as sensitizers in DSSCs. Porphyrins with electron-donating amino moieties provided improved charge separation and better charge-injection efficiencies for the studied dual-push-pull dyes. Attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopy of the porphyrin dyes on TiO2 suggest that both p-carboxyphenyl groups are attached onto TiO2, thereby resulting in strong attachment. Among these dyes, cis-Zn2BC2A, with two electron-donating 3,6-ditertbutyl-phenyl-carbazole groups and dual-anchoring p-carboxyphenyl groups, showed the highest efficiency of 4.07%, with JSC=9.81mAcm-2, VOC=0.63V, and FF=66%. Our results also indicated a better photostability of the studied dual-anchored sensitizers compared to their mono-anchored analogues under identical conditions. These results provide insight into the developments of a new generation of high-efficiency and thermally stable porphyrin sensitizers.
Real-time and indicator-free detection of aqueous nitric oxide with hydrogel film
(2010-05-31)
Chao, Yu-Chiang
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Yeh, Shih-De
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Zan, Hsiao-Wen
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Chang, Gao-Fong
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Meng, Hsin-Fei
A sensing hydrogel film is demonstrated for real-time and indicator-free detection of nitric oxide (NO) in aqueous solution. The film composed of NO probe 11,16-bisphenyl-6,6,21,21-tetramethyl-m-benzi-6,21-porphodimetheno-chloro-zinc(II) and host polymer poly(2-hydroxyethyl methacrylate). The water-containing nature of this sensing hydrogel film makes the surface area high. The response time is bellow 10 s. This sensing hydrogel film also shows high selectivity, sensitivity, and stability in various pH values. (C) 2010 American Institute of Physics. [doi:10.1063/1.3425895]
Solid-state sensing tip for zinc ion with double parallel optical fibers embedded in fluorescent hydrogel
(2015-11-01)
Su, Heng-Tsan
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Tsai, May-Jywan
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Chang, Gao-Fong
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Hung, Chen-Hsiung
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Lin, Hung-Cheng
A tip-shaped zinc ion solid-state sensor is made by two parallel optical fibers embedded closely in a sensing hydrogel film. The film is made of poly(2-hydroxyethyl methacrylate) (poly HEMA) hydrogel mixed with the selective fluorescent probe meso-2,6-Dichlorophenyltripyrrinone (TPN-Cl-2) with weight ratio of 0.025 wt%. A 405 nm laser output is sent from one fiber and the 622 nm fluorescence of the doped hydrogel is collected by the second fiber. Each fiber diameter is 370 mu m (core is 300 mu m), whose sum is roughly the tip diameter. The 0.4 cm by 0.5 cm tip has real-time response for zinc ion concentration over 10(-6) M, with marginal signal for 10(-7) M. The tip is inserted inside an oyster and successfully detects the zinc ions, showing that the sensor works in complex body fluid and tolerates certain mechanical stress. To show the potential application for medicine, the sensing film is applied for primary neuronal cultures. We report for the first time zinc ions release at concentration levels 10(-6)-10(-7) M to the medium under stress conditions of ischemia, inflammation, and intoxication. Furthermore, this correlates with the zinc levels detected by biochemical assay. Such sensing tip has great potential for biomedical monitoring ex vivo or in vivo. (C) 2015 Elsevier B.V. All rights reserved.
Solid-state sensing tip for zinc ion with double parallel optical fibers embedded in fluorescent hydrogel (vol 26, pg 429, 2015)
(2016-08)
Su, Heng-Tsan
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Tsai, May-Jywan
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Chang, Gao-Fong
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Hung, Chen-Hsiung
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Lin, Hung-Cheng