• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.145-152
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• 2016

In this study, CuO was introduced on MWCNTs dispersed with Au nanoparticles to improve the glucose sensing capability of electrochemical biosensors. Nano-cluster shaped CuO was synthesized due to the presence of Au nanoparticle, which affects glucose sensing performance. The biosensor featuring CuO/Au@MWCNTs nanocomposite as an electrode material when 0.1 mole of CuO was synthesized showed the highest sensitivity of $504.1{\mu}A\;mM^{-1}cm^{-2}$, which is 4 times better than that of MWCNTs based biosensors. In addition, it shows a wider linear range from 0 to 10 mM and lower limit of detection (LOD) of 0.008 mM. These results demonstrate that CuO/Au@MWCNTs nanocomposite sensors are superior to other CuO based biosensors which are attributed that the nano-cluster shaped CuO is favorable for the electrochemical reaction with glucose molecules.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.493-500
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• 2023

In this study, we developed an impedance sensor capable of controlling electrode polarization by coating iridium oxide (IrO_x) on the surface of the screen-printed carbon electrode. IrO_x was deposited on the surface of carbon electrodes according to the number of cycles (0~50 cycles) by cyclic voltammetry. Observation of scanning electron microscope images revealed that the size and number of IrO_x particles increased as the number of cycles increased. The changes in impedance responses as a function of the NaCl concentration of the as-obtained sensors were investigated using electrochemical impedance spectroscopy. The sensors manufactured in 50 cycles exhibited the best coefficient of determination and reproducibility, attributed to the well-controlled electrode polarization. We further demonstrated the usefulness of the IrO_x-based sensor as a diagnosis sensor for dry eye syndrome by comparing the results of the commercially available osmometer and our sensor using actual solution samples.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.107-112
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• 2014

Using a chlorosulphonated polyethylene rubber solution for a binder of graphite powder and ferrocene for a mediator, a rose leaf tissue-embedded biosensor was built. Linearity on the Hanes-Woolf plot showed the reduction of the substrate was attained through the catalytic power of the rose peroxidase in the experimental range of electrode potential. Furthermore, 10 or more electrochemical parameters demonstrated that the electrode exerts its sensing ability quantitatively. The foregoing gave the full conviction that rose tissue can be used in place of the currently marketed enzyme for the practical use of enzyme electrode.

• The Safety technology
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• no.190
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• pp.24-26
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• 2013

최근 화학물질 안전사고가 잇따라 발생하면서 사업장 내 안전제품을 구비하고 안전한 작업환경을 조성하려는 움직임이 확산되고 있다. (주)유민에쓰티(대표 유흥근)는 이러한 화학물질 안전사고를 예방하기 위해 불산, 염소 등의 화학약품 유출을 감지하는 센서장치를 생산하는 곳이다. 이곳은 누수감지센서를 비롯해 스팀검출센서, 옥외용 강산 검출센서, 유기성액체 검출센서 등을 개발하면서 산업안전제품시장에서 무서운 신장세를 드러내고 있다. 특히 지난 2008년에는 인쇄전자 기반의 필름형 누수감지센서를 세계 최초로 개발해 국무총리상을 수상하면서 우수한 기술력을 자랑하기도 했다. 또한 국내외 약 50여 건에 이르는 특허 획득을 통해 품질을 인증받았으며, 미국전기전자공학회(IEEE)에 소개되는 등 해외에서도 기술력을 인정받고 있다. 이처럼 (주)유민에쓰티는 끊임없는 기술 개발로 안전한 작업현장을 조성하는 데 이바지하고 있다. 하지만 유민에스티의 모든 관계자들은 사업장 내 안전이 먼저 확보됐었기에 이 같은 성장이 가능했다고 입을 모아 말한다. 제조업 특성상 안전사고 발생률이 높은데도 불구하고 2003년 설립된 이후 단 한 건의 안전사고와 산재가 발생하지 않았을 만큼 철저한 안전관리를 전개하고 있는 것이다. 안전을 바탕으로 눈부신 성장을 하고 있는 (주)유민에쓰티를 찾아가봤다.

• Journal of the Korean Chemical Society
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• v.52 no.2
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• pp.197-202
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• 2008

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.28-32
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• 2003

본 논문은 시료의 양을 최소화하고 혈중 요소 및 혈당 농도에 대한 정확한 측정을 위하여 최근에 개발된 전기화학형 마이크로 전극형 센서의 간략한 소개 및 전기적인 특성에 관하여 요약하는 것에서 출발하여 센서로부터 전기신호를 발생시키는 signal conditioning 회로의 설계, microprocessor를 이용한 digital 값으로의 변환 및 data 취득, 취득한 data를 측정된 혈당량 및 요소량으로의 변환 저장 display까지의 휴대용 계측기의 prototype 개발에 관하여 기술한다. 이 계측기는 미량의 혈액채취 한번으로 농도를 측정하는 측정모드와, 측정된 data를 찾아보기 위한 검색모드로 작동시킬 수 있다. Microprocessor의 기능을 최대한 사용하여 측정기의 크기를 소형화하였으며 LCD(Liquid crystal display)틀 채택하는 등 저전력 회로로 구현하였다.

• Electrical & Electronic Materials
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• v.26 no.10
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• pp.3-9
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• 2013

• Electrical & Electronic Materials
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• v.21 no.3
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• pp.27-35
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• 2008

• Journal of Sensor Science and Technology
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• v.33 no.3
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• pp.158-164
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• 2024

We developed a self-operated paper pump that can maintain a nearly constant flow rate of an aqueous solution along a paper strip channel in paper-based analytical devices (PADs). The quasi-stationary flow rate was controlled by increasing the crosssectional channel area (capillary force) using a fan-shaped absorption pad coupled with a paper strip channel. The flow rate is regulated by varying the fan angle of the circular absorbing pad. Furthermore, the flow rate can be increased by furnishing a hollow cavity at the center of a conventional paper strip channel. The rate was regulated by varying the length of the hollow paper channel in the flow rate range of 5.1-26.4 mm/min. As a preliminary work, a paper-pump-coupled PAD was fabricated, and its CV detection capability was evaluated for the redox reaction of Fe(CN)₆^+4/+3. The combination of a paper pump with a PAD resulted in an ideal CV curve with a higher limiting current and faster response time. These results are interpreted well by the Levich equation, which suggests that the paper pump is a very useful component in paper-based sensors.

• Journal of the Korean Electrochemical Society
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• v.10 no.2
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• pp.150-154
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• 2007

Redox complexes to transport electrodes from biomaterial to electrodes are very important part in commercial biosensor industry. A novel osmium redox complex was synthesized by the coordinating pyridine group with osmium metal. A novel osmium complex is described as $[Os(dme-bpy)_2(ap-im)Cl]^{+/2+}$. We have been studied the electrochemical characteristics of this osmium complex with electrochemical techniques such as cyclic voltammetry and chronoamperommetry. In order to immobilize osmium redox complexes on the electrode, we deposited gold nano-particles on screen printed carbon electrode(SPE). The electrical signal converts the osmium redox films into an electrocatalyst for glucose oxidation. The catalytic currents were monitored that the catalytic currents were linearly increased from 1 mM to 5 mM concentrations of glucose.