• 한국정보통신학회논문지
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• 제21권2호
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• pp.345-352
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• 2017

본 논문에서는 전원전압 1V에서 동작하는 산소 및 과산화수소 기반의 혈당전류를 측정할 수 있는 통합형 정전압분극장치를 설계하고 제작하였다. 정전압분극장치는 저전압 OTA, 캐스코드 전류거울 그리고 모드 선택회로로 구성되어 있다. 정전압분극장치는 산소 및 과산화수소 기반에서 혈당의 화학반응으로 발생하는 전류를 측정할 수 있다. OTA의 PMOS 차동 입력단의 바디에는 순방향전압을 인가하여 문턱전압을 낮추어 낮은 전원전압이 가능하도록 하였다. 또한 채널길이변조효과로 인한 전류의 오차를 줄이기 위해 캐스코드 전류거울이 사용되었다. 제안한 저전압 정전압분극장치는 Cadence SPECTRE를 이용하여 설계하였으며, 매그나칩 $0.18{\mu}m$ CMOS 공정을 이용하여 제작되었으며 회로의 크기는 $110{\mu}m{\times}60{\mu}m$이다. 전원전압 1.0V에서 소모전류는 최대 $46{\mu}A$이다. 페리시안화칼륨($K_3Fe(CN)_6$)을 사용하여 제작된 정전압분극장치의 성능을 확인하였다.

• 약학회지
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• 제29권3호
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• pp.117-123
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• 1985

A clorimetric determination method of pyruvic acid using hydroxylamine was studied. Hydroxylamine was reacted with pyruvic acid to form complex compound in the presence of Cu(II) ion. Optimal conditions for the quantitative analysis were investigated and the structure of complex was examined spectrometrically. The molar ratio (2:1) and the stability constant ($1.88{\times}10^{4}$) of the complex were measured. It was the characteristic feature of this method that the commonly encountered interfering substances such as fructose, glucose and lactic acid do not infuence the measurement of pyruvic acid.

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 하계학술발표회
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• pp.250-251
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• 2002

혈당의 비침습적인 측정의 필요성은 잦은 채혈로 인한 감염의 우려, 필요할 때마다 채혈의 고통 없이 혈당을 측정할 수 있다는 장점 때문에 지난 20여 년 동안 활발히 연구되어 왔다. 근적외선 및 원적외선 흡수분광법, 라만분광법, Polarization rotation 또는 Stimulated Raman 측정법, 온도측정법, 통계적 분석법, 전처리연구 등 많은 분야에서 접근하고 있지만 아직까지는 in vivo 측정에 성공하고 있지 못하고 있다 [1]. (중략)

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1970년도 제9차 학술대회
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• pp.95.1-95.1
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• 1970

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1571-1574
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• 2013

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1179-1182
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• 2005

To facilitate the cell based robot research, we presented a micro-mechanical force measurement system for the biological muscle actuators, which utilize glucose as a power source for potential application in a human body or blood vessels. The system is composed of a micro-manipulator, a force transducer with a glass probe, a signal processor, an inverted microscope and video recoding system. Using this measurement system, the contractile force and frequency of the cardiac myocytes were measured in real time and the magnitude of the contractile force of each cardiac myocyte on a different condition was compared. From the quantitative experimental results, we estimated that the force of cardiac myocytes is about $20{\sim}40\;{\mu}$N, and showed that there is difference between the control cells and the micro-patterned cells.

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.145-148
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• 1992

A microbial sensor for BOD (Biochemical Oxygen Demand) measurement has been developed by immobilizing Hansenula anomala in a polyacrylamide gel. The optimum pH and temperature for BOD measurement using this sensor were pH 7.0 and $30^{\circ}C$, respectively. The response time was 30 min. A linear relationship was observed between the potential and the concentration below 44 ppm BOD. The potential was reproducible within ${\pm}9%$ of the relative error when a sample solution containing 20 mg/l of glucose and 20 mg/l of glutamic acid was employed. The effect of various compounds on BOD estimation was also examined. The potential output of the sensor was almost constant for 30 days. The relative error in BOD estimation was within ${\pm}10%$.

• 한국응용과학기술학회지
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• 제39권1호
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• pp.52-62
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• 2022

소변검사 전 냉/해동 반복과 해동 과정에 따라 대표적인 임상 화학검사 측정값의 변화를 확인함으로써 소변검사의 안정성과 품질 개선방안을 모색하고자 하였다. 조사 대상자는 모두 건강한 남성 10명이었으며 이들의 소변 검체를 이용하여 냉/해동 안정성(freeze and thaw stability) 실험을 진행하였다. Micro-albumin과 Amylase의 경우 시간이 경과 됨에 따라 37℃에서는 통계적 유의성은 없었으나, 42℃와 60℃에서는 시간의 경과에 따른 결과가 통계적으로 유의한 변동이 있었고, BUN, Creatinine, Uric acid와 Glucose에서는 통계적으로 유의한 변동이 있었다. Long term의 안정성 결과, 7일이 지난 후에는 Glucose의 변이는 증가하였고, 60℃에서는 Amylase가 감소하는 양상을 보였다. Glucose와 Amylase의 경우 시간의 경과에 따른 결과가 통계적으로 유의한 변동이 있었다. 신뢰성 있는 검사결과를 얻기 위해서는 소변 시료의 채취, 보관 및 저장 등을 비롯한 요검사의 정확한 표준화가 필요하며 생체 물질별 안정성 확보를 위한 조건들의 체계적 연구가 필요하다.

• Journal of Acupuncture Research
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• 제24권3호
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• pp.81-97
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• 2007

Objectives: The purpose of this study is to investigate the anti-oxidative effect of electroacupuncture at Kokchi($LI_{11}$) in rats. Methods: A study administer AAPH to the abdominal cavity of rats and stimulate Kokchi($LI_{11}$) of the rat that lead to oxidative stress by electropuncture. And the study survey serum albumin, total bilirubin, LDL-cholesterol, LDH, Glucose, GOT, GPT and measure SOD activity, GSH concentration, catalase activity, NO concentration, MDA concentration. Results: 1. At the analysis of blood chemistry Albumin and Glucose significantly increase at $LI_{11}$-NR group, $LI_{11}$-EA group than at control group and holder group. LDL cholesterol, GOT, GPT decrease meaningfully. 2. As results of measurement at liver, SOD, Catalase represnet significantly increase at $LI_{11}$-NR group and $LI_{11}$-EA group than at control group and holder group. 3. Glutathione has some increases at the $LI_{11}$-NR group and $LI_{11}$-EA group than at the control group and the holder group. 4. As a result of measurement of NO and MDA's content, the content of NO decrease at the $LI_{11}$-NR group than at the control group. That reduces more meaningfully at the $LI_{11}$-EA group than at the control group. MDA has a significant decrease at the $LI_{11}$-NR group and the $LI_{11}$-EA group. 5. At the histological analysis, the study confirm that the density of intracellular cytoplasm in the liver tissue decreases at the control group as compared with the Normal group and the size of cell increases. Conclusions : These results suppose that electroacupuncture at $LI_{11}$ has an anti-oxidant effect in human.

• Journal of Microbiology and Biotechnology
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• 제21권2호
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• pp.204-211
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• 2011

To yield high concentrations of protein expressed by genetically modified Escherichia coli, it is important that the bacterial strains are cultivated to high cell density in industrial bioprocesses. Since the expressed target protein is mostly accumulated inside the E. coli cells, the cellular product formation can be directly correlated to the bacterial biomass concentration. The typical way to determine this concentration is to sample offline. Such manual sampling, however, wastes time and is not efficient for acquiring direct feedback to control a fedbatch fermentation. An E. coli K12-derived strain was cultivated to high cell density in a pressurized stirred bioreactor on a pilot scale, by detecting biomass concentration online using a capacitance probe. This E. coli strain was grown in pure minimal medium using two carbon sources (glucose and glycerol). By applying exponential feeding profiles corresponding to a constant specific growth rate, the E. coli culture grew under carbon-limited conditions to minimize overflow metabolites. A high linearity was found between capacitance and biomass concentration, whereby up to 85 g/L dry cell weight was measured. To validate the viability of the culture, the oxygen transfer rate (OTR) was determined online, yielding maximum values of 0.69 mol/l/h and 0.98mol/l/h by using glucose and glycerol as carbon sources, respectively. Consequently, online monitoring of biomass using a capacitance probe provides direct and fast information about the viable E. coli biomass generated under aerobic fermentation conditions at elevated headspace pressures.