• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.130-137
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• 2014

A strip sensor based on $PbO_2$/carbon paste electrode was prepared by a screen-printing method, and employed to electrochemically determine the concentration of fruit sweeteners(i.e. glucose, sucrose, and fructose). The $PbO_2$/carbon paste electrode could monitor electrocatalytic oxidation of organic compounds such as carbohydrates, and measure the levels of natural sweeteners without enzyme. Severe interference from ascorbic acid was effectively reduced by modifying the electrode surface with a Nafion membrane. The response level of the Nafion/$PbO_2$/carbon paste electrode increased in the order of fructose, sucrose, and glucose, which corresponds to the order of sweetness perceived by humans.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.47-52
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• 2015

To improve both the GOD immobilization capability and sensitivity of MWCNTs-based biosensor electrode, the electrode was prepared by adding different quantities of GO. The addition of GO increased hydrophilicity and the surface free energy of electrodes for glucose sensing as well as the dispersion of MWCNTs. In addition, the GOD immobilization capability was enhanced and the sensitivity was improved up to $121{\mu}A\;mM^{-1}$ even though having a high $K_m$ value (0.105) when adding 0.05 g GO to 0.05 g MWCNTs. These experimental results were attributed to the fact that the improvement in dispersion stability for MWCNTs, hydrophilicity, and surface free energy of electrode surface due to the addition of GO affected GOD immobilization capability.

• Journal of the Korean Electrochemical Society
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• v.17 no.1
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• pp.30-36
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• 2014

Redox complexes to transport electrons from enzyme to electrodes are very important part in glucose sensor. Pentacyanoferrate-bound aniline ($Fe(CN)_5$-aminopyridine), was prepared as a potential redox mediator in a glucose dehydrogenase (GDH)-glucose sensor. The synthesized pyridyl-$NH_2$ to pentacyanoferrate was characterized by the electrochemical and spectroscopic methods. A amperometric enzyme-linked electrode was developed based on GDH, which catalyses the oxidation of glucose. Glucose was detected using GDH that was co-immobilized with an $Fe(CN)_5$-aminopyridine and gold nano-particles (AuNPs) on ITO electrodes. The $Fe(CN)_5$-aminopyridine and AuNPs immobilized onto ITO electrodes provided about a two times higher electrochemical response compared to that of a bare ITO electrode. As glucose was catalyzed by wired GDH, the electrical signal was monitored at 0.4 V versus Ag/AgCl by cyclic voltammetry. The anode currents was linearly increased in proportion to the glucose concentration over the 0~10 mM range.

• Journal of Sensor Science and Technology
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• v.28 no.1
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• pp.47-51
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• 2019

Sweat-based glucose sensors are being widely investigated and researched as they facilitate painless and continuous measurement. However, because the concentration of sweat glucose is almost a hundred times lower than that of blood glucose, it is important to develop electrochemical sensing electrode materials that are highly sensitive to glucose molecules for the detection of low concentrations of glucose. The preparation of a flexible and ultra-sensitive sensor for detection of sweat glucose is presented in this study. Oxygen and nitrogen are removed from the surface of a polyimide film by exposure to a CO2 laser; hence, laser-induced graphene (LIG) is formed. The fabricated LIG electrode showed favorable properties of high roughness and good stability, flexibility, and conductivity. After the laser scanning, Pt nanoparticles (PtNP) with good catalytic behavior were electrodeposited and the glucose sensor thus developed, with a LIG/PtNP hybrid electrode, exhibited a high order of sensitivity and detection limit for sweat glucose.

• KSBB Journal
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• v.19 no.1
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• pp.27-32
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• 2004

2-Dimensional fluorescence sensor has a wide range of excitation and emission wavelengths, that some biogenic fluorphors in a biological process can be monitored simultaneously. The production processes of 5-aminolevulinic aicd (ALA) by recombinant E. coli BL21 (DE3) pLysS harboring plasmid pFLS45 were on-line monitored by a 2-dimensional fluorescence sensor The characteristics of fluorescence spectrum was dependent upon physical and biological factors of a bioprocess such as culture pH, cell mass etc. Some off-line data were correlated to the fluorescence intensity well, which was monitored at some combination of excitation and emission wavelengths by the 2-dimensional fluorescence sensor.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.465-468
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• 2003

A microdialysis coupled flow injection amperometric biosensor was calibrated to measure the concentration of glucose using 7 standard samples from 10ml to 70ml of glucose solution. The output of the sensor increased linearly with an increase in the glucose concentration with an $R^2$ correlation of 0.99. The amperometric biosensor was then applied to measure the. glucose concentration of 2 commercial samples(Orange and Pineapple juice) and the results compared with HPLC. Around 12% error was observed in glucose concentration measurements of the samples analyzed. The sensor has potential in rapid measurement once the calibration is done. Potential for on-line sensing is also discussed.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1536-1537
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• 2007

본 논문은 당뇨병의 지표 물질인 glucose의 농도를 극미량의 시료를 사용하여 정량할 수 있는 방법을 개발하기 위해 organic/inorganic 네트웍에 의해 안정화된 나노입자 효소를 이용하여 초소형 효소 전극을 개발하였다. 전극은 실리콘 웨이퍼상에 반도체 공정을 이용하여 마이크로 크기의 금 박막 전극을 제작하였다, Organic/Inorganic 물질과 함께 합성된 glucose oxidase 나노입자는 20nm 크기로 투과형 전자현미경 (Transmission Electron Microscope:TEM)으로 관찰하고, 푸리에변환 적외선분광법(Fourier transform infrared spectrophotometer : FTIR) 을 이용하여 분석하였고, 전극 특성을 알아보기 위해 Potentiostat/Galvanostat을 사용하여 전기 화학 실험을 하였다. 제작된 전극은 시간대 전류법으로 glucose의 농도에 따른 감도를 측정하였다. 실험결과에 따라 전극의 표면에서 발생하는 전류는 glucose의 농도에 비례함을 알 수 있었다. 또한 순환 전압전류법을 통하여 감도를 측정하였다.

• Journal of Plant Biotechnology
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• v.35 no.2
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• pp.141-145
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• 2008

In this study, glucose-inducible intergenic sequences were used to generate bioreporters of the cyanobacterium Synechocystis sp. PCC 6803 that could monitor environmental pollutants. Luciferase genes LuxAB from the marine bacterium Vibrio fischeri under the control of glucose-inducible intergenic seqeucens of eight genes (atpI, ndbA, ctaD1, tkt, pgi, pdh, ppc, and cydA) were successfully expressed in the cyano-bacterial transformants, showing 5-25 fold increases in biolumeniscence upon exposure to glucose. In addition, glucose-inducible cyanobacterial bioreporters were very sensitive to various chemicals such as heavy metals ($Hg^{2+}$, $Cu^{2+}$, $Zn^{2+}$), electron transport inhibitors (DCMU, DBMIB, $CN^-$), and antibiotics (chloramphenicol and rifampicin). These glucose-inducible cyanobacterial bioreporters would be useful to develop biosensors for rapid screening of environmental samples.

• Journal of the Korean Electrochemical Society
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• v.17 no.3
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• pp.164-171
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• 2014

A highly sensitive and selective non-enzymatic glucose sensor has gained great attention because of simple signal transformation, low-cost, easily handling, and confirming the blood glucose as the representative technology. Until now, glucose sensor has been developed by the immobilization of glucose oxidase (GOx) on the surface of electrodes. However although GOx is quite stable compared with other enzymes, the enzyme-based biosensors are still impacted by various environment factors such as temperature, pH value, humidity, and toxic chemicals. Non-enzymatic sensor for direct detecting glucose is an attractive alternative device to overcome the above drawbacks of enzymatic sensor. Many efforts have been tried for the development of non-enzymatic sensors using various transition metals (Pt, Au, Cu, Ni, etc.), metal alloys (Pt-Pb, Pt-Au, Ni-Pd, etc.), metal oxides, carbon nanotubes and graphene. In this paper, we show that Ni-based nano-particles (NiNPs) exhibit remarkably catalyzing capability for glucose originating from the redox couple of $Ni(OH)_2/NiOOH$ on the surface of ITO electrode in alkaline medium. But, these non-enzymatic sensors are nonselective toward oxidizable species such as ascorbic acid the physiological fluid. So, the anionic polymer was coated on NiNPs electrode preventing the interferences. The oxidation of glucose was highly catalyzed by NiNPs. The catalytically anodic currents were linearly increased in proportion to the glucose concentration over the 0~6.15 mM range at 650 mV versus Ag/AgCl.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.5
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• pp.991-1000
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• 2021

Among non-invasive blood glucose detection technologies, the optical technique is a method that uses light reflection, absorption, and scattering characteristics when passing through a biological medium. It reduces pain or discomfort in measurement and has no risk of infection. So it is becoming a major flow of blood glucose detection research. Among them, near-infrared spectroscopy has a disadvantage in that the complexity increases when analyzing signals detected due to interferences between proteins and acids that share a similar absorption function with blood glucose molecules. In this study, a non-invasive sensor system with multiple near-infrared bands was designed and manufactured to alleviate the deterioration of blood glucose detection function that may occur due to skin absorption of near-infrared rays. A blood survey was conducted to verify the system, and the degree of blood glucose response in the blood was collected as spectral data, and the results of this study were quantitatively verified in terms of correlation between the data and blood glucose.