• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.92.2-92.2
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• 2018

빠르고 정확한 글루코오스 농도 측정은 의료, 식품, 환경 등 다양한 산업에서 매우 중요하다. 글루코오스 산화효소를 기반으로 하는 현재 글루코오스 센서는 높은 감도와 선택성을 갖지만 온도변화나 다른 화학물 등 환경에 취약하다는 단점이 있다. 따라서 최근 비효소식 글루코오스 센서에 대한 연구가 활발히 진행되고 있다. 금속-유기 구조체(MOFs)는 금속이온과 유기물 리간드로 구성된 결정성 다공체로, 큰 기공 크기와 비표면적, 안정성 등을 특징으로 갖는다. 대부분의 MOFs는 전기전도도가 낮지만 금속이온의 산화/환원, 리간드의 화학적 개질을 통해 전기화학분야에서도 다양하게 연구되고 있다. 본 연구에서는 글루코오스 농도 측정을 위한 전극촉매로 다양한 금속이온과 리간드로 이루어진 MOFs를 합성했다. 표면분석을 통해 MOFs의 전기화학적 처리 전후의 구조와 성질 변화를 관찰했고 전기화학적 분석을 통해 금속이온과 리간드의 종류가 감도, 선택성 등 글루코오스 검지 성능에 주는 영향을 분석했다. 그 결과 Ni, Co 기반의 MOFs가 글루코오스에 대해 높은 감도를 보였으며 이를 통해 MOFs의 글루코오스 센서로의 응용 가능성을 확인했다.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.1
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• pp.39-45
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• 2005

As a basic research for the development of a non-invasive blood glucose sensor using millimeter waves, we have presented a method for measuring the dielectric properties of high loss dielectrics, based on the reflection method, and investigated the variation of the dielectric properties of glucose-water and glucose -0.9% NaCl solutions in the 10～90 GHz range. In the proposed method, a minimal reflection condition is formed by placing a specially-chosen low-loss plane-parallel plate in front of a high-loss medium under test at a given frequency range. Using the minimal power reflection coefficient and the corresponding frequency at this condition, tile dielectric properties of the medium can be determined. The measured results on pure water have shown the adequacy of the proposed method. The measured results on glucose-water and glucose -0.9% NaCl solutions in the 10～90 GHz range showed that the variations of the dielectric properties of glucose solutions according to the change of their glucose concentration were maximum in the 30～45 GHz range. From these facts we concluded that the variation of about 3 mole/L in the glucose solutions must be distinguished With the measurement accuracies of ±0.1 dB and ±0.01 GHz.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.730-734
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• 2005

Flow injection analysis (FIA) system was developed to monitor glucose concentrations in biotechnological processes. A fiber optic oxygen sensor was used to determine consumption of oxygen concentration by reaction of immobilized glucose oxidase (GOD). The GOD was immobilized on VA-Epoxy carrier and integrated into FIA system. A calibration curve for glucose was obtained in the range of 0.5 $g/L{\sim}3.0$ g/L.

• Journal of the Korean Electrochemical Society
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• v.16 no.2
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• pp.74-80
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• 2013

We investigate the formation of nanoporous gold (NPG) surfaces by anodization in three carboxylic acid (formic acid, acetic acid, and propionic acid) solutions and the electrochemical oxidation of glucose at NPG surfaces. Among three carboxylic acids, formic acid provided the most efficient conditions for NPG formation towards glucose oxidation. The optimized conditions during anodization in formic acid for glucose oxidation were 5.0 V of applied potential and 4 hour of reaction time. Electrocatalytic activities for glucose oxidation at NPG surfaces prepared by anodization in carboxylic acids were examined under the absence and presence of chloride ions, which were compared to those observed at NPG prepared in oxalic acid solutions. The application NPG prepared by optimized anodization conditions in formic acid to the amperometric detection of glucose was demonstrated.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.73.2-77
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• 2000

A possibility of the implementation of a quartz crystal sensor to the detennination of chemical oxygen demand is examined by checking the electrochemical behavior of the sensor in a glucose solution. Since the surface of a quartz crystal has to be oxidized, a relatively active metal is coated on the surface of a usual 9 MHz AT-cut crystal. The electrochemical behavior is investigated by measuring the changes of current, resonant frequency and resonant resistance while a constant potential is applied. The crystal is installed in a specially designed container, and a QUartz crystal analyzer is utilized to measure the frequency and resistance simultaneously. The variations of the measurements are examined at different concentrations of glucose solution and the effect of the concentration is analyzed to find a proper relation between the concentration and the measurements. It is fOlmd that a linear relation between the concentration of less than 900 Dpm and the peak current when a constant potential of -180 m V vs. Ag/ AgCI reference is applied.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.263-268
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• 1989

To maximize the performance of recombinant cell fermentation process through optimizing environmental conditions, the production of invertase from recombinant Saccharomyces cerebisiae Containing SUC2 gene was studied as a model. The recombinant cells showed biphasic growth on glucose. Since the promoter of the SUC2 is regulated by the concentration of glucose in the medium, expression of invertase by recombinant yeast began when the glucose concentration decreased in a range of 0.25-0.4 g/L during the batch culture. Plasmid segregation occured frequently during glucose fermentation, and infrequently during ethanol oxidation. A rapid appearance of invertase activity with glucose was observed under nonaerated condition, and the maximum specific invertase activity was about 1.5 times as high as under aerobic condition, In fed batch culture, when n low level of glucose was continuously supplied to the tormentor after the time of glucose depletion during growth phase, specific and total invertase activity increased about 1.7 and 2.9 fold, respectively, in a batch culture.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.406-410
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• 1990

The influence of glucose concentration on cell growth rate and on the expression level of the strong promoter obtained from alkali-tolerant Bacillus sp. YA-14 chromosomal DNA was studied. In fed-batch culture, the promoter activity could be maximized by maintaining a very low level of glucose concentration in the broth and glucose consumption rate below 1.08g/g cell-h. The induction of the promoter was possible by addition of sporulation medium after the cell was grown in growth medium with only low level of CAT activity.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.379-381
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• 2001

굴절율 측정에 의하여 당 성분을 정량하는 방법을 이용한 장치로, 글루코오스의 환원성에 기초하여 산화ㆍ환원 반응을 이용한 적정법이나 흡광도 측정법과 비교하여 시약이 필요없고 시간이 단축되는 장점이 있다. 그리고, 보통의 굴절율 측정기(예로 Abbe refractometer)가 당 농도 0.5％일 때의 굴절율 값 단위로 측정되는 한계를 극복하여 본 당 모니터링 장치는 바탕 물질과의 굴절율 차이를 증폭한 값으로 data(differential refractive index)를 얻을수 있으므로 글루코오스 농도 0.01% 단위까지 정량할 수 있어서 0.1% 이하의 저농도도 측정 가능하며 그 이상의 농도 범위에서도 측정 오차를 줄일수 있는 장점이 있다. (중략)

• KSBB Journal
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• v.25 no.4
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• pp.351-356
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• 2010

To increase the production of ethanol by using sugar from lignocellulosic biomass, pentose and hexose have to be fermented simultaneously by yeast. The effects of mixed sugar and nitrogen on ethanol production by immobilized Pichia stipitis KCCM 12009 were investigated. When optimal mixed sugar and nitrogen concentration were 5% (Glucose/Xylose = 3:1) and 1%, respectively, ethanol concentration produced by immobilized P. stipitis was 19-20 g/L. In repeated fed-batch by immobilized P. stipitis, all glucose was consumed very quickly at 1-3% mixed sugar concentration. But, xylose consumption was decreased as the mixed sugar concentration increased. Also, ethanol (5.6 g/L) was stably produced and ethanol production rate was 0.13 g/$L{\cdot}h$ in immobilized cell reactor (ICR) with 1% mixed sugar (Glucose/Xylose = 3:1) as feeding media.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.314-319
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• 1997

Sugars in Korean jujube fruit and jujube fruit drinks were studied. The sugars in Korean jujube fruit were extracted by boiling with water for 30min and stirring for 1 hour at 7$0^{\circ}C$ after soaking in the water for 24 hours at 4$^{\circ}C$ followed by crushing. Korean jujube fruit was found to contain 25% of sucrose, 21.2% of fructose and 20.7% of glucose. Korean jujube fruit drinks of V company and H company were found sugar composition of 5.9% and 6.9% of sucrose, 2.2% and 2.1% of fructose and 2.4% and 2.4% of glucose, respectively. No other mono- and oligosaccharides were detected in the test of TLC and HPLC. A viscous material in jujube fruit and jujube fruit drinks was separated by ethanol fractionation, and identified as pectin by 1H-NMR and carbazole analysis. Pectin of Korean jujube fruit, jujube drink of V company and jujube drink of H company was found to contain 61, 58 and 55% of galacturonic acid, respectively.