• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.379-383
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• 2005

This research aims to develop DNA chip array without an indicator. We fabricated microelectrode array by photolithography technology. Several DNA probes were immobilized on an electrode. Then, indicator-free target DNA was hybridized by an electrical force and measured electrochemically. Cyclic-voltammograms (CVs) showed a difference between DNA probe and mismatched DNA in an anodic peak. Immobilization of probe DNA and hybridization of target DNA could be confirmed by fluorescent. This indicator-free DNA chip microarray resulted in the sequence-specific detection of the target DNA quantitatively ranging from $10^{-18}\;M\;to\;10^{-5}$ M in the buffer solution. This indicator-free DNA chip resulted in a sequence-specific detection of the target DNA.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.31-34
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• 1997

A semiconductor microelectrode array has been successfully used in obtaining single unit recordings from medial giant nerve of clay fish, rat saphenous nerve and abdominal ganglia of aplysia. The recording device fabricated using silicon microfabrication techniques is a depth-probe type and, previously, has been mostly used to record from central nerve system of vertebrates. From invertebrates, and also from peripheral nerves of vertebrates, however, the quality of the recorded signal depends heavily on the recording conditions, such as the proximity of the electrode site to the nerve cells and the size of the neuron. We have modeled the signal to noise ratio as unctions of these parameters and compared the experimental data with the calculated values thus obtained.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.145-146
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• 1998

A planar-type silicon microelectrode array has been fabricated and used successfully in obtaining simultaneous multichannel recordings from peripheral nerve of invertebrates. This paper demonstrates that planar-type semiconductor electrode arrays are useful for studying traveling wave properties of action potential.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.147-148
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• 1998

In this paper, we developed the process for depth-probe type silicon microelectrode arrays. The process consists of four mask steps only. The steps are for defining sites, windows, and for shaping probe using plasma etch from above, and for shaping using wet etch from below, respectively. The probe thickness is controlled by dry etching, not by impurity diffusion. We used gold electrodes with a triple dielectric system consisting of oxide/nitride/oxide. The shank of the probe taper from 200um to tens of urn tip and has 30 um thickness.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.5
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• pp.85-91
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• 2010

In this paper, we present details on fabrication of single-cell electroporation microdevice, practical experiments of single-cell electroporation with our fabricated microdevice. Also, the continuous electroporation for the continuous flow of cells is used for high-throughput electroporation. The delivery efficiency and cell viability tests are provided and the successful GFP transfection into cells is also evaluated with a fluorescent microscope after electroporation. This device enables to reduce the size of samples and thus the use of small amount of reagents. Also, it makes it possible to permit to avoid cell discrimination (transfected cells versus non-transfected cells) encountered when traditional bulk electroporation is held.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2009.10a
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• pp.267-267
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• 2009

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.65-70
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• 2006

In this study, a DNA chip with a microelectrode array was fabricated using microfabrication technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5 end were immobilized on the gold electrodes by DNA arrayer. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 concentrated at the electrode surface through association with formed hybrid. It suggested that this DNA chip could recognize the sequence specific genes.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1136-1141
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• 2004

In recent years, demands on microelectrode have been greatly enhanced because of its potential applications and mass production of microelectrodes is needed. An electrochemical fabrication is used as an method for the simple and cheap fabrication of multi microelectrodes. In this paper, one dimensional microelectrode array is used for fabricating of multi electrodes. A diffusion layer which is formed near the electrode surface has an effect on the shape error of multi microelectrodes. The optimal distance between electrodes to minimize shape errors of multi electrodes is investigated. Multi microelectrodes which has several tens of and hundreds of micrometer in diameter are fabricated at a time.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.5
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• pp.286-292
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• 2004

In this study, an integrated microelectrode array was fabricated on glass slide using microfabrication technology. Probe DNAs consisting of mercaptohexyl moiety at their 5-end were spotted on the gold electrode using micropipette or DNA arrayer utilizing the affinity between gold and sulfur. Cyclic voltammetry in 5mM ferricyanide/ferrocyanide solution at 100 ㎷/s confirmed the immobilization of probe DNA on the gold electrodes. When several DNAs were detected electrochemically, there was a difference between target DNA and control DNA in the anodic peak current values. It was derived from specific binding of Hoechst 33258 to the double stranded DNA due to hybridization of target DNA. It suggested that this DNA chip could recognize the sequence specific genes. It suggested that multichannel electrochemical DNA microarray is useful to develop a portable device for clinical gene diagnostic System.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.7
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• pp.729-737
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• 2004

In this paper, a DNA chip with a microelectrode array was fabricated using microfabrication technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5 end were immobilized on the gold electrodes by DNA arrayer. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 concentrated at the electrode surface through association with formed hybrid. It suggested that this DNA chip could recognize the sequence specific genes.