Browsing by Author "Yang, Chung-Shi"

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A Perfusion-based Micro Opto-fluidic System (PMOFS) with GNP Signal Enhancement for Continuously In-situ Immune Sensing
(2009)
Tseng, Yuan-Tai
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Yang, Chung-Shi
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Tseng, Fang-Gang
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
This paper proposes a novel design of a reusable biosensor for in-situ and continuous protein detection. The sensing probe was practiced by the integration of a fiber optic interferometry (FOI) sensor accommodated in a micro opto-fluidic chip covered with a microdialysis membrane and surface regeneration mechanism for regenerable detection. Gold-nanoparticles (GNPs) labeled anti-rabbit IgG was used to enhance the protein conjugation signal due to an elongated optical path length by GNPs layer, providing extended interference fringe shift for signal enhancement. On the other hand, surface regeneration of the sensor was realized through local pH level manipulation by employing a photoactivable molecule, o-Nitrobenzaldehyde (o-NBA), for the elution of immune complex. Experimental results showed the o-NBA elution method can keep the pH variation to be limited close to the neighboring region of the sensor surface, providing a self-contained sensing system. In-situ immune detection and surface regeneration of the sensing probe was achieved successfully for two identical cycles on the same sensing probe, and 10ng/ml of detection limit can be approached.
In-situ Formation and Assembly of Gold Nanoparticles by Gum Arabic as Efficient Photothermal Agent for Killing Cancer Cells
(2013-10-01)
Liu, Ching-Ping
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Lin, Fong-Sian
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Chien, Chih-Te
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Tseng, Sheng-Yang
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Luo, Chih-Wei
Probing the binding kinetics of proinflammatory cytokine-antibody interactions using dual color fluorescence cross correlation spectroscopy
(2011)
Wu, Chia-Yan
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Huang, Chuan-Keng
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Chung, Chao-Yu
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Huang, I-Ping
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Hwu, Yeukuang
Dual color fluorescence cross correlation spectroscopy (FCCS) was used to investigate quantitatively the binding kinetics of tumor necrosis factor (TNF alpha) with TNF alpha antibody (anti-TNF alpha) following fluorescent labeling. Through the analysis of the auto correlation curves of fluorescence correlation spectroscopy (FCS), diffusion coefficients of 100.06 +/- 4.9 mu m(2) s(-1) and 48.96 +/- 2.52 mu m(2) s(-1) for Alexa488-TNF alpha and Atto647N-anti-TNF alpha were obtained. In addition, the calculated hydrodynamic diameters of the Alexa488-TNF alpha and Atto647N-anti-TNF alpha were approximately 4.89 +/- 0.24 nm and 9.99 +/- 0.52 nm, respectively, which agrees with the values of 5.20 +/- 1.23 nm and 9.28 +/- 0.86 nm for the native TNF alpha and the anti-TNF alpha as determined from dynamic light scattering measurements. For the binding kinetics, association (k(on)) and dissociation (k(off)) rate constants were (1.13 +/- 0.08) x 10(4) M(-1) s(-1) and (1.53 +/- 0.19) x 10(-3) s(-1) while the corresponding dissociation constant (K(d)) at 25 degrees C was (1.36 +/- 0.10) x 10(-7) M. We believe this is the first report on the binding kinetics for TNF alpha-antibody recognition in the homogeneous phase. Using this technology, we have shown that controlled experiments can be performed to gain insight into molecular mechanisms involved in the immune response.