Browsing by Author "Huang, G. Steven"

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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
;
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
Application of Nanobiotechnology to Construct a Piezoelectric Sensor Matrix Sensing the Flexibility of Immunoglobulin
(2007)
Huang, G. Steven
;
Chen, Yu-Shiun
;
Lin, Xin-Yau
;
材料科學與工程學系奈米科技碩博班
;
Graduate Program of Nanotechnology , Department of Materials Science and Engineering
We have constructed a piezoelectric sensor matrix with the capability of measuring the flexibility of immunoglobulin. The matrix consisted of 6 independent quartz crystal microbalance (QCM) coated with gold nanoparticles (GNP) of 3.5, 5, 12, 17, and 37 nm, and BSA. The detection was performed simultaneously. Antiserum against GNP bound to QCMs coated with 3.5 nm GNP and maximized for 5 nm GNP-coated QCM. To our best knowledge, this is the first biosensor sensing the topological change and flexibility of biological macromolecule.
DNA sequencing using electrical conductance measurements of a DNA polymerase
(2013-06-01)
Chen, Yu-Shiun
;
Lee, Chia-Hui
;
Hung, Meng-Yen
;
Pan, Hsu-An
;
Chiou, Jin-Chern
The development of personalized medicine-in which medical treatment is customized to an individual on the basis of genetic information-requires techniques that can sequence DNA quickly and cheaply. Single-molecule sequencing technologies, such as nanopores, can potentially be used to sequence long strands of DNA without labels or amplification, but a viable technique has yet to be established. Here, we show that single DNA molecules can be sequenced by monitoring the electrical conductance of a phi29 DNA polymerase as it incorporates unlabelled nucleotides into a template strand of DNA. The conductance of the polymerase is measured by attaching it to a protein transistor that consists of an antibody molecule (immunoglobulin G) bound to two gold nanoparticles, which are in turn connected to source and drain electrodes. The electrical conductance of the DNA polymerase exhibits well-separated plateaux that are similar to 3 pA in height. Each plateau corresponds to an individual base and is formed at a rate of similar to 22 nucleotides per second. Additional spikes appear on top of the plateaux and can be used to discriminate between the four different nucleotides. We also show that the sequencing platform works with a variety of DNA polymerases and can sequence difficult templates such as homopolymers.
DNA sequencing using electrical conductance measurements of a DNA polymerase (Retracted article. See vol. 10, pg. 563, 2015)
(2013-06-01)
Chen, Yu-Shiun
;
Lee, Chia-Hui
;
Hung, Meng-Yen
;
Pan, Hsu-An
;
Chiou, Jin-Chern
The development of personalized medicine-in which medical treatment is customized to an individual on the basis of genetic information-requires techniques that can sequence DNA quickly and cheaply. Single-molecule sequencing technologies, such as nanopores, can potentially be used to sequence long strands of DNA without labels or amplification, but a viable technique has yet to be established. Here, we show that single DNA molecules can be sequenced by monitoring the electrical conductance of a phi29 DNA polymerase as it incorporates unlabelled nucleotides into a template strand of DNA. The conductance of the polymerase is measured by attaching it to a protein transistor that consists of an antibody molecule (immunoglobulin G) bound to two gold nanoparticles, which are in turn connected to source and drain electrodes. The electrical conductance of the DNA polymerase exhibits well-separated plateaux that are similar to 3 pA in height. Each plateau corresponds to an individual base and is formed at a rate of similar to 22 nucleotides per second. Additional spikes appear on top of the plateaux and can be used to discriminate between the four different nucleotides. We also show that the sequencing platform works with a variety of DNA polymerases and can sequence difficult templates such as homopolymers.
DNA sequencing using electrical conductance measurements of a DNA polymerase (Retracted article. See vol. 10, pg. 563, 2015)
(2013-06-01)
Chen, Yu-Shiun
;
Lee, Chia-Hui
;
Hung, Meng-Yen
;
Pan, Hsu-An
;
Chiou, Jin-Chern
The development of personalized medicine-in which medical treatment is customized to an individual on the basis of genetic information-requires techniques that can sequence DNA quickly and cheaply. Single-molecule sequencing technologies, such as nanopores, can potentially be used to sequence long strands of DNA without labels or amplification, but a viable technique has yet to be established. Here, we show that single DNA molecules can be sequenced by monitoring the electrical conductance of a phi29 DNA polymerase as it incorporates unlabelled nucleotides into a template strand of DNA. The conductance of the polymerase is measured by attaching it to a protein transistor that consists of an antibody molecule (immunoglobulin G) bound to two gold nanoparticles, which are in turn connected to source and drain electrodes. The electrical conductance of the DNA polymerase exhibits well-separated plateaux that are similar to 3 pA in height. Each plateau corresponds to an individual base and is formed at a rate of similar to 22 nucleotides per second. Additional spikes appear on top of the plateaux and can be used to discriminate between the four different nucleotides. We also show that the sequencing platform works with a variety of DNA polymerases and can sequence difficult templates such as homopolymers.
Fabrication of optical reflectors by using of elastomer with self-organized undulations
(2008-08-01)
Wang, Jui-Hao
;
Shih, Teng-Kai
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Chen, Chia-Fu
;
Chen, Kuang-Chung
;
Chen, Chien-Chung
Back-surface diffusive reflectors have been widely applied in many optical systems to promote the efficiency used in system. In this work, we propose a novel way to fabricate a soft diffusive reflector by using of silicone (polydimethylsiloxane, PDMS). High-reflectance substrates were first fabricated by mixing nanoscaled TiO2 powders with PDMS polymers, and then microscale wave-like undulations were spontaneously developed after the substrates were dipped into H2SO4/HNO3 solutions. After optical examination, a TiO2/PDMS plate comprising microscale undulations, which can surely serve as a reflector, could reflect and diffuse light effectively. Besides, all fabrication processes can be executed in the ambient environment and at low temperature. This proposed method has a potential for mass production in the future. (c) 2008 Elsevier B.V. All rights reserved.
Generation, inhalation delivery and anti-hypertensive effect of nisoldipine nanoaerosol
(2014-12-01)
Onischuk, A. A.
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Tolstikova, T. G.
;
Baklanov, A. M.
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Khvostov, M. V.
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Sorokina, I. V.
Nisoldipine is a dihydropyridine subclass calcium channel blocker with low oral bioavailability. Therefore, novel drug delivery systems able to enhance nisoldipine bioavailability are urgently needed. Here the nanoaerosol pulmonary administration of nisoldipine is investigated in experiments with WISTAR and ISIAH rats. The drug aerosol inhalation scheme includes an evaporation-condensation aerosol generator, inhalation chambers for rats, and aerosol spectrometer (to control aerosol concentration and size distribution). The particle mean diameter and number concentration are within the ranges 10-200 nm and 10(3)-2 x 10(7) cm(-3), respectively. The chemical composition of nanoaerosol particles was shown by means of liquid chromatography to be identical with the maternal drug. Using nose-only exposure chambers, the rat lung deposition efficiency was evaluated as a function of particle diameter. The dose-dependent effect from aerosolized nisoldipine was compared with that from the intravenous and oral drug delivery. In particular, it was found that nisoldipine aerosol administration is essentially more effective than traditional oral treatment, i.e. it gives the same blood pressure reduction as the oral treatment at the body deposited dose about 100 times less. (C) 2014 Elsevier Ltd. All rights reserved.
Gold nanoparticles regulate the blimp1/pax5 pathway and enhance antibody secretion in B-cells
(2014-03-28)
Lee, Chia-Hui
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Syu, Shih-Han
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Chen, Yu-Shiun
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Hussain, Saber M.
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Onischuk, Andrei Aleksandrovich
Nanoparticles are potential threats to human health and the environment; however, their medical applications as drug carriers targeting cancer cells bring hope to contemporary cancer therapy. As a model drug carrier, gold nanoparticles (GNPs) have been investigated extensively for in vivo toxicity. The effect of GNPs on the immune system, however, has rarely been examined. Antibody-secreting cells were treated with GNPs with diameters ranging from 2 to 50 nm. The GNPs enhanced IgG secretion in a size-dependent manner, with a peak of efficacy at 10 nm. The immune-stimulatory effect reached a maximum at 12 h after treatment but returned to control levels 24 h after treatment. This enhancing effect was validated ex vivo using B-cells isolated from mouse spleen. Evidence from RT-PCR and western blot experiments indicates that GNP-treatment upregulated B-lymphocyte-induced maturation protein 1 (blimp1) and downregulated paired box 5 (pax5). Immunostaining for blimp1 and pax5 in B-cells confirmed that the GNPs stimulated IgG secretion through the blimp1/pax5 pathway. The immunization of mice using peptide-conjugated GNPs indicated that the GNPs were capable of enhancing humoral immunity in a size-dependent manner. This effect was consistent with the bio-distribution of the GNPs in mouse spleen. In conclusion, in vitro, ex vivo, and in vivo evidence supports our hypothesis that GNPs enhance humoral immunity in mouse. The effect on the immune system should be taken into account if nanoparticles are used as carriers for drug delivery. In addition to their toxicity, the immune-stimulatory activity of nanoparticles could play an important role in human health and could have an environmental impact.
Measuring the flexibility of immunoglobulin by gold nanoparticles
(2006-11-08)
Huang, G. Steven
;
Chen, Yu-Shiun
;
Yeh, Hsiao-Wei
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材料科學與工程學系奈米科技碩博班
;
奈米科技中心
We measured the flexibility of Fab and Fc arms of immunoglobulin using gold nanoparticles (GNPs). Enzyme-linked immunosorbent assay was performed to measure the affinity of anti-5 nm GNP antiserum against various sizes of GNPs. The flexibility of Fc was also measured by electron microscopy. The restricted binding affinity indicated that only a very limited amount of freedom was allowed for the Fab-Fab hinge, while Fab-Fc showed a much larger degree of freedom.
Nanosurface design of dental implants for improved cell growth and function
(2012-08-24)
Pan, Hsu-An
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Hung, Yao-Ching
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Chiou, Jin-Chern
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Tai, Shih-Ming
;
Chen, Hsin-Hung
A strategy was proposed for the topological design of dental implants based on an in vitro survey of optimized nanodot structures. An in vitro survey was performed using nanodot arrays with dot diameters ranging from 10 to 200 nm. MG63 osteoblasts were seeded on nanodot arrays and cultured for 3 days. Cell number, percentage undergoing apoptotic-like cell death, cell adhesion and cytoskeletal organization were evaluated. Nanodots with a diameter of approximately 50 nm enhanced cell number by 44%, minimized apoptotic-like cell death to 2.7%, promoted a 30% increase in microfilament bundles and maximized cell adhesion with a 73% increase in focal adhesions. An enhancement of about 50% in mineralization was observed, determined by von Kossa staining and by Alizarin Red S staining. Therefore, we provide a complete range of nanosurfaces for growing osteoblasts to discriminate their nanoscale environment. Nanodot arrays present an opportunity to positively and negatively modulate cell behavior and maturation. Our results suggest a topological approach which is beneficial for the design of dental implants.
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.
Psoralea corylifolia extract ameliorates experimental osteoporosis in ovariectomized rats
(2007)
Tsai, Meng-Hsiun
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Huang, G. Steven
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Hung, Yao-Ching
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Bin, Liu
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Liao, Lung-Te
We evaluated the protective effect of Psoralea corylifolia L. (PCL) extract on the ovariectomized (OVX) rat model. The biochemical markers of bone turnover, calcium metabolism, and calcium balance were examined. PCL extract (25 mg or 50 mg/kg body weight/day) was orally administrated to OVX rats for 3 months. PCL extract did not alter weight gain or uterus weight in OVX rats. PCL extract significantly increased serum Ca (calcium) levels (p < 0.05, vs. OVX group) as well as decreased urinary Ca excretion (p < 0.05, vs. OVX group) in OVX rats. The upregulation of serum osteocalcin level by ovariectomy was suppressed by treatment with PCL extract in rats (p < 0.05, vs. OVX group). PCL extract increased bone mineral density at 50 mg/kg body weight/day in OVX rats (p < 0.05, vs. OVX group). Our results indicate that orally administrated PCL extract can decrease urinary calcium excretion and decrease serum osteocalcin in OVX rats, resulting in positive effects on bone mineral density as well as bone formation. In conclusion, our studies showed that PCL might be a potential candidate for treatment of postmenopausal osteoporosis.
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.
The spatial and temporal control of cell migration by nanoporous surfaces through the regulation of ERK and integrins in fibroblasts
(2013-01-01)
Pan, Hsu-An
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Liang, Jia-You
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Hung, Yao-Ching
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Lee, Chia-Hui
;
Chiou, Jin-Chern
Nanotopography controls cell behaviours, such as cell adhesion and migration. However, the mechanisms responsible for topology-mediated cellular functions are not fully understood. A variety of nanopores was fabricated on 316L stainless steel to investigate the effects of spatial control on the growth and function of fibroblasts, the temporal regulation of integrins, and their effects on migration. The NIH-3T3 fibroblast cell line was cultured on the nanopore surfaces, whose pore diameters ranged from 40 to 210 nm. The 40 and 75 nm nanopores enhanced cell proliferation, focal adhesion formation and protein expression of vinculin and beta-tubulin after 24 h of incubation. Integrin expression was analysed by qPCR, which showed the extent of spatial and temporal regulation achieved by the nanopores. The protein expression of pERK1/2 was greatly attenuated in cells grown on 185 and 210 nm nanopore surfaces at 12 and 24 h. In summary, the 40 and 75 nm nanopore surfaces promoted cell adhesion and migration in fibroblasts by controlling the temporal expression of integrins and ERK1/2. The current study provides insight into the improvement of the design of stainless steel implants and parameters that affect biocompatibility. The ability to regulate the expression of integrin and ERK1/2 using nanopore surfaces could lead to further applications of surface modification in the fields of biomaterials science and tissue engineering. (C) 2012 Elsevier Ltd. All rights reserved.
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.
Topographical control of cell-cell interaction in C6 glioma by nanodot arrays
(2014-05-21)
Lee, Chia-Hui
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Cheng, Ya-Wen
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Huang, G. Steven
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材料科學與工程學系
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分子醫學與生物工程研究所
Nanotopography modulates the physiological behavior of cells and cell-cell interactions, but the manner of communication remains unclear. Cell networking ( syncytium) of astroglia provides the optimal microenvironment for communication of the nervous system. C6 glioma cells were seeded on nanodot arrays with dot diameters ranging from 10 to 200 nm. Cell viability, morphology, cytoskeleton, and adhesion showed optimal cell growth on 50-nm nanodots if sufficient incubation was allowed. In particular, the astrocytic syncytium level maximized at 50 nm. The gap junction protein Cx43 showed size-dependent and time-dependent transport from the nucleus to the cell membrane. The transport efficiency was greatly enhanced by incubation on 50-nm nanodots. In summary, nanotopography is capable of modulating cell behavior and influencing the cell-cell interactions of astrocytes. By fine-tuning the nanoenvironment, it may be possible to regulate cell-cell communications and optimize the biocompatibility of neural implants.