Browsing by Author "Hong, Meng-Yen"

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A protein transistor made of an antibody molecule and two gold nanoparticles
(2012-03-01)
Chen, Yu-Shiun
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Hong, Meng-Yen
;
Huang, G. Steven
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材料科學與工程學系
;
生醫電子轉譯研究中心
A major challenge in molecular electronics is to attach electrodes to single molecules in a reproducible manner to make molecular junctions that can be operated as transistors. Several attempts have been made to attach electrodes to proteins, but these devices have been unstable. Here, we show that self-assembly can be used to fabricate, in a highly reproducible manner, molecular junctions in which an antibody molecule (immunoglobulin G) binds to two gold nanoparticles, which in turn are connected to source and drain electrodes. We also demonstrate effective gating of the devices with an applied voltage, and show that the charge transport characteristics of these protein transistors are caused by conformational changes in the antibody. Moreover, by attaching CdSe quantum dots to the antibody, we show that the protein transistor can also be gated by an applied optical field. This approach offers a versatile platform for investigations of single-molecule-based biological functions and might also lead to the large-scale manufacture of integrated bioelectronic circuits.
A protein transistor made of an antibody molecule and two gold nanoparticles (vol 7, pg 197, 2012)
(2012-04-01)
Chen, Yu-Shiun
;
Hong, Meng-Yen
;
Huang, G. Steven
;
生醫電子轉譯研究中心
;
Biomedical Electronics Translational Research Center
Camellia sinensis tea melanin suppresses transformation of the aryl hydrocarbon receptor and prevents against dioxin-induced toxicity in mice
(2008-02-01)
Hung, Yao-Ching
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Huang, Guewha Steven
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Sava, Vasyl M.
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Makan, Svetlana Y.
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Hong, Meng-Yen
The suppressive effects of Camellia sinensis tea melanin (CSTM) on transformation of aryl hydrocarbon receptor (AhR) induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were disclosed for the first time. CSTM strongly inhibited TCDD-induced toxicity with IC50 equalling 20.4 mu g mL(-1). Daily administration of CSTM (40 mg kg(-1), p.o.) prevented TCDD-induced body weight loss, ameliorated TCDD-induced mortality and prevented TCDD-induced hepatomegaly and thymic atrophy. Co-administration of CSTM significantly inhibited TCDD-induced hepatic CYP1 A1 activity. CSTM retarded transformation of AhR in vitro. In animals treated with CSTM, the antibody-secreting cells produced significantly (P < 0.05) more antibodies (32-34%) than the antigen control. Administration of TCDD caused a suppression of antibody-forming cells of 29-33% against the antigen control level. Co-administration of CSTM restored immunity to the control level. We demonstrated that CSTM directly competed with TCDD during the transformation of AhR and suppressed the downstream activation of genes associated with TCDD toxicity.
Picogram detection of metal ions by melanin-sensitized piezoelectric sensor
(2007-10-31)
Huang, G. Steven
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Wang, Meng-Te
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Su, Chia-Wei
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Chen, Yu-Shiun
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Hong, Meng-Yen
A heavy metal ion sensor was constructed by cross-linking melanin onto the gold electrode of quartz crystal microbalance (QCM). A mercury ion sensitivity of 518 +/- 37 Hz/ppm was observed, a substantial increase in sensitivity compared to previous reports of 10-50 Hz/ppm with the limit of detection at 5 ppb. Detection of other metal ions including Sn2+, Ge4+, Li+, Zn2+, Cu2+, Bi3+, Co2+, Al3+, Ni2+, Ag+, and Fe3+ were also performed. Unexpectedly, binding of Mn7+, Ph2+, Cd2+, and Cr3+ increased resonant frequencies. The surface profile of melanin thin film upon binding to metal ions was investigated by atomic force microscopy (AFM). Structural change of melanin upon binding to metal ions was characterized by circular dichroism and by infrared spectroscopy. The current study provides the first example of melanin-coated piezoelectric sensor showing high sensitivity and selectivity to metal ions. (c) 2007 Elsevier B.V. All rights reserved.
Self-assembly of an antireflective moth-like structure using antibody-functionalized nanowires and nanopore arrays
(2011-11-25)
Chen, Yu-Shiun
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Hung, Ning
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Chou, Li-Jen
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Chiou, Jin-Chern
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Hong, Meng-Yen
A novel framework to fabricate moth-like nanopillar arrays was proposed. In this scheme, nanowires were first cross-linked with anti-gold nanoparticle (GNP) antibodies and mixed with the nanopore array pre-deposited by GNP, which was then followed by centrifugation. An optimal success rate of 95% was finally obtained by choosing nanorods with an aspect ratio of 5:1 by modifying with 10 ng mL(-1) antibodies, and by inserting them into a pore array pre-deposited with 54.4 mu M GNP. The nanopillar arrays thus fabricated showed high levels of antireflective efficiency across a broad wavelength. Here we demonstrate the assembly of nanowires and nanopores into nanopillar arrays by the assistance of antibody-antigen binding. The application of bio-nano-interaction provides an economic, time-saving, and throughput approach to manipulating objects on the nanoscale.
Thea sinensis melanin prevents cisplatin-induced nephrotoxicity in mice
(2007-07-01)
Hung, Yao-Ching
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Huang, G. Steven
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Lin, Li-Wei
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Hong, Meng-Yen
;
Se, Pei-San
The preventive effect of Thea sinensis melanin (TSM) against cisplatin-induced nephrotoxicity was studied on ICR mice. Animals were given 20 mg/kg i.p. of cisplatin, and TSM was injected i.p. in doses 10-40 mg/kg 2 h before intoxication. The protective effects were evidenced by a complete inhibition of the cisplatin-induced elevation of serum Blood Urea nitrogen (BUN), prevention of oxidative stress, and complete blockade of cisplatin-induced elevation of serum creatinine. TSM by itself, however, did not affect the renal functional parameters, including serum BUN and creatinine. Real-time RT-PCR was applied to quantify mRNA levels of cisplatin-treated mouse kidney compared to normal mouse kidney for selected marker genes. Cisplatin treatment increases mRNA levels 40-fold for glutathione-S-transferases (Gstp2), 15-fold for soluble epoxide hydrolase (Ephx1), 15-fold for lipocalin 2 (Lcn2), 9-fold for lysozyme (Lyz), 5-fold for UDP glycosyltransferase 2 (Utg2b), 30-fold for survival motor neuron (Smn1), 30-fold for guanidinoacetate methyltransferase (Gamt), 80-fold for urine retinol binding protein (Rbp4), 60-fold for aminopeptidase N (Apn), 60-fold for cytochrome P450 (Cyp2d18), and 100-fold for ornithine aminotransferase (Oat). Pre-administration of TSM restored normal expression of marker genes for cisplatin-treated mouse kidneys. TSM by itself, however, did not affect the transcription for marker genes. Results obtained demonstrate that TSM pre-administration can prevent the renal toxic effects of cisplatin. (c) 2007 Elsevier Ltd. All rights reserved.