Browsing by Author "Shiu, Jau-Ye"

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Addressable Cell Microarrays via Switchable Superhydrophobic Surfaces
(2010)
Shiu, Jau-Ye
;
Kuo, Chiung Wen
;
Whang, Wha-Tzong
;
Chen, Peilin
;
材料科學與工程學系
Here we describe an approach to fabricate addressable cell microarrays, which are based on the patterned switchable superhydrophobic surfaces. The switchable superhydrophobic surfaces were prepared by roughening the surfaces of fluoropolymers on the electrodes. Upon the application of 150 V to the underneath electrodes, the water contact angle on the roughened fluoropolymer surfaces could be decreased from 163 degrees to less than 10 degrees allowing the deposition of fibronectin, which could guide the growth of the cells. Our result indicated that it was possible to control the spatial distribution of two different cells on the cell microarrays. (C) Koninklijke Brill NV, Leiden, 2010
Behavior of single DNA molecules in the well-ordered nanopores
(2008-10-03)
Shiu, Jau-Ye
;
Whang, Wha-Tzong
;
Chen, Peilin
;
材料科學與工程學系
;
Department of Materials Science and Engineering
Here we describe a simple approach to fabricate robust three-dimensional periodic porous nanostructure inside the microchannels. In this approach, the colloidal crystals were first grown inside the microchannel using an evaporation-assisted self-assembly process. Then the void spaces among the colloidal crystals were filled with epoxy-based negative tone photoresist. After subsequent development and nanoparticle removal, the well-ordered nanoporous structures inside the microchannel could be fabricated. Depending on the size of the colloidal nanoparticles, periodic porous nanostructures inside the microchannels with cavity size of 330 and 570 nm have been obtained. The dimensions of interconnecting pores for these cavities were around 40 and 64 nm, respectively. The behavior of single X-phage DNA molecules in these nanoporous structures was studied using fluorescence microscopy. It was found that the length of DNA molecules oscillated in the nanoporous structures. The measured length for A-phage DNA was larger in the 330 nm cavity than those measured in the 570 nm cavity. (C) 2008 Elsevier B.V. All rights reserved.
Functionalized silver nanowires for live cell study
(2008-06-05)
Kuo, Chiung-Wen
;
Shiu, Jau-Ye
;
Wei, Kung Hwa
;
Chen, Peilin
;
材料科學與工程學系
The biocompatibility of the surface-functionalized silver nanowires has been investigated in two cell lines. It was found that the functionalized silver nanowires with 200 nm diameter and length up to a few mu m can be internalized by cells. The cytotoxicity of the silver nanowires was found to depend on their surface modifications. It was also demonstrated that the surface-enhanced Raman scattering (SERS) could be measured on the silver nanowires, which added additional functionality to the silver nanowires.
Monolithic integration of well-ordered nanoporous structures in the microfluidic channels for bioseparation
(2007-08-31)
Kuo, Chiung-Wen
;
Shiu, Jau-Ye
;
Wei, Kung Hwa
;
Chen, Peilin
;
材料科學與工程學系
Gel electrophoresis and capillary gel electrophoresis are widely used for the separation of biomolecules. With increasing demand in the miniaturized devices such as lab-on-a-chip, it is necessary to integrate such a separation component into a chip format. Here, we describe a simple approach to fabricate robust three-dimensional periodic porous nanostructures inside the microchannels for the separation of DNA molecules. In our approach, the colloidal crystals were first grown inside the microchannel using evaporation assisted self-assembly process. Then the void spaces among the colloidal crystals were filled with epoxy-based negative tone photoresist (SU-8). UV radiation was used to cure the photoresist at the desired area inside the microchannel. After subsequent development and nanoparticle removal, the well-ordered nanoporous structures inside the microchannel were obtained. Our results indicated that it was possible to construct periodic porous nanostructures inside the microchannels with cavity size around 300 nm and interconnecting pores around 30 nm. The mobility of large DNA molecules with different sizes was measured as a function of the applied electric field in the nanoporous materials. It was also demonstrated that I kilo-base pair (kbp) DNA ladders could be separated in such an integrated system within 10 min under moderate electric field. (c) 2007 Published by Elsevier B.V.
Morphological control of CuPc and its application in organic solar cells
(2008-10-15)
Hsiao, Yu-Sheng
;
Whang, Wha-Tzong
;
Suen, Shich-Chang
;
Shiu, Jau-Ye
;
Chen, Chih-Ping
We have prepared organic photovoltaic (OPV) cells possessing an ideal bulk heterojunction (BHJ) structure using the self-assembly of copper phthalocyanine (CuPc) as the donor material and fullerene (C(60)) as the acceptor. The variable self-assembly behavior of CuPc on a diverse range of substrates (surface energies) allowed us to control the morphology of the interface and the degree of carrier transportation within the active layer. We observed rod-like CuPc structures on indium-tin oxide (ITO), poly(3,4-ethylenedioxythiophene)poly(4-styrenesulfonate) (PEDOT: PSS) and Au substrates. Accordingly, the interfaces and continuing transport path between CuPc and fullerene domains could be greatly improved due to the ideal BHJ structure. In this paper, we discuss the mechanisms of producing CuPc rod-like films on ITO, PEDOT: PSS and Au. The OPV cell performance was greatly enhanced when a mixture of horizontal and vertical CuPc rods was present on the PEDOT: PSS surfaces, i.e. the power conversion efficiency was 50 times greater than that of the corresponding device featuring a planar CuPc structure.
Nanofluidic system for the studies of single DNA molecules
(2008-07-01)
Kuo, Chiung-Wen
;
Wei, Kung Hwa
;
Lin, Chun-Hsun
;
Shiu, Jau-Ye
;
Chen, Peilin
Here, we describe a simple and low-cost lithographic technique to fabricate size-controllable nanopillar arrays inside the microfluidic channels for the studies of single DNA molecules. in this approach, nanosphere lithography has been employed to grow a single layer of well-ordered close-packed colloidal crystals inside the microfluidic channels. The size of the polymeric colloidal nanoparticles could be trimmed by oxygen plasma treatment. These size-trimmed colloidal nanoparticles were then used as the etching mask in a deep etching process. As a result, well-ordered size-controllable nanopillar arrays could be fabricated inside the microfluidic channels. The gap distance between the nanopillars could be tuned between 20 and 80 nm allowing the formation of nanofluidic system where the behavi of of a single lambda-phage DNA molecule has been investigated. It was found that the lambda-phage DNA molecule could be fully stretched in the nanofluidic system formed by nanopillars with 50 nm gap distance at a field of 50 V/cm.
Observation of enhanced cell adhesion and transfection efficiency on superhydrophobic surfaces
(2010)
Shiu, Jau-Ye
;
Kuo, Chiung-Wen
;
Whang, Wha-Tzong
;
Chen, Peilin
;
材料科學與工程學系
It was found that cells attached preferentially on the roughened area of patterned superhydrophobic surfaces allowing the formation of cell microarrays with the advantages of improved cell adhesion, natural separation of colonies and enhanced transfection efficiency.
Superhydrophobic Coatings for Microdevices
(2008)
Shiu, Jau-Ye
;
Whang, Wha-Tzong
;
Chen, Peilin
;
材料科學與工程學系
;
Department of Materials Science and Engineering
We have developed two simple techniques to impart superhydrophobic properties to the surfaces of microdevices. In the first approach, thin films of a fluoropolymer were spin-coated on the device surfaces followed by an oxygen plasma treatment. By varying the oxygen plasma treatment time, the water contact angles on device surface could be tuned from 120 degrees to 169 degrees. In the second approach, a nanoimprint process was used to create nanostructures on the devices. To fabricate nanoimprint stamps with various feature sizes, nanosphere lithography was employed to produce a monolayer of well-ordered close-packed nanoparticle array on the silicon surfaces. After oxygen plasma trimming, metal deposition and dry etching process, silicon stamps with different nanostructures were obtained. These stamps were used to imprint nanostructures on hydrophobic coatings, such as Teflon, over the device surfaces. The water contact angle as high as 167 degrees was obtained by the second approach. (c) Koninklijke Brill NV, Leiden, 2008