• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.627-629
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• 2003

In this work fiber-optic biosensor that has been used in medical applications was developed. And we can monitored the concentration of glucose and lactate in blood sample by using developed fiber-optic glucose and lactate sensor. Glucose oxidase(GOD) and Lactate oxidase(LOD) were immobilized by using acrylamide adhesive and zeolite on the tip of the optic fiber.

• Journal of Biosystems Engineering
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• v.33 no.4
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• pp.276-281
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• 2008

A flow injection analysis method (FIA), which analyzes sample conditions after injecting a sample and reagents into a continuous stream, are recognized as the most adequate analyzing method according to the increase of sampling frequency, the decrease of measuring time and the diversity of measuring targets. Specially, the FIA is considered to be used effectively for the control of a fermentation process to produce fermentation food and useful microbial production by activation of a fermentation industry for development of biological materials. In this study, a flow injection analysis sensor unit was developed for on-line monitoring of the fermentation process. The performance was verified by on-line measuring the concentration of glucose of the fermentation process of wine. The glucose concentrations of the samples were measured every 12 hours during the whole fermentation process and compared with those by a HPLC. The concentration relative errors of glucose on the fermentation process of wine showed below 30% within 72 hours and over 50% after the 72 hours. The sensor unit had potential to on-line monitoring of the fermentation process but some problems to overcome for an commercial application.

• Journal of IKEEE
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• v.11 no.4
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• pp.293-296
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• 2007

A novel sensitive and non-invasive ring-type glucose probe was designed and measured. The magnitude and phase of return loss change with different concentration of the glucose solution inside the loop structure. Ring type probe is more advantageous than open ended probe to measure electrical characteristics under the skin. The maximum difference of return loss was 0.94 for the concentration difference of 0% and 20% at 285MHz and more sensitive in low frequency.

• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.154-160
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• 1990

Hydroxypropyl methacrylate polymeric membranes having tertiary amine moiety were prepared to control the release rate of insulin in response to the concentration of glucose. Hydroxypropyl methacrylate was copolymerized with N, N'-diethylaminoethylacrylate. Its water content was increased with decreasing the pH of the medium and was reversible with variation of the pH of the medium. The permeation coefficient of insulin through copolymer membrane was also increased with decreasing the pH of the medium. Combining this copolymer membrane and the glucose oxidase immobilized membrane as a sensor for glucose, composite membrane was prepared. The permeability of this composite membrane was increased with addition of glucose.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.248-250
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• 2002

본 논문은 당뇨병의 지표물질인 glucose의 농도를 극미량의 시료를 사용하여 정량 할 수 있는 방법을 개발하기 위하여 효소 고정화 전극을 제작하였다. 전극은 실리콘 웨이퍼상에 마이크로 크기의 전극을 반도체 공정을 이용하여 제작하였고, 전기 화학적 방법으로 마이크로 전극에 전도성 고분자 Polypyrrole(PPy) 및 glucose oxidase(GOx)를 고정화한 고감도의 전기화학 전극을 개발하였다. 도전성 고분자의 전기 화학적 중합은 순환 전압 전류법으로 하였으며, 용액의 액성에 따른 효소의 표면 전하를 이용하여, 도전성 고분자를 코팅한 전극에 일정한 전압을 인가하고 GOx를 도우핑 하였다. 제작된 전극은 시간대 전류법으로 glucose의 농도에 따른 감도 측정결과 마이크로 리터의 시료에 $5{\mu}A$/decade를 얻었다. 전극의 표면분석은 Scanning electron microscopy(SEM), Energy dispersive X-ray spectroscopy(EDX)를 이용하였다.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.415-420
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• 1999

A biochemical oxygen demand (BOD) sensor loaded with Candida sp. was designed and constructed for the quick measurement of the concentrations of biologically assimilable organic substances dissolved in water. The sensitivity of the sensor was higher for glucose, acetic acid, aspartic acid and glutamic acid than that for lactose, sucrose and lactic acid. The sensitivities of BOD sensors loaded with $Zn^{2+}$ tolerant and intact strains were almost identical while the sensitivity of sensor loaded with Cd$^{2+}$ tolerant strain was considerably lower. The sensitivities of the sensors loaded with intact or $Zn^{2+}$ tolerant strains did not change with the concentration of $Cd^{2+}$ in the aqueous solution while the sensitivity of the sensor loaded with $Cd^{2+}$ tolerant strain decreased slightly. The sensitivities of the sensors loaded with intact strain, $Zn^{2+}$ or $Cd^{2+}$ tolerant strains were not affected by the concentration of $Zn^{2+}$ in the aqueous solution.n.

• Journal of Sensor Science and Technology
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• v.4 no.4
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• pp.23-28
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• 1995

The ISFET glucose and sucrose sensors containing platinum electrode and photopolymeric enzyme membrane were fabricated. The platinum working electrode was used for the electrolysis of hydrogen peroxide, which was the other product of the enzyme reaction, to improve sensing characteristics of the sensors. In order to improve response time, photo-crosslinkable polymer(PVA-SbQ) was used to the matrix for the enzyme immobilized membrane. The characteristics of glucose and sucrose sensors were investigated according to the variation of platinum electrode area. The response time was about $3{\sim}5$ minutes and determinations of glucose and sucrose in the range of about $30{\sim}300mg/dl$ could be possible.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.52-57
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• 2023

This study is a basic research for the development of high performance flexible electrode material. To enhance its electrochemical property, CuO nanoparticles (CuO NPs) were introduced and dispersed on surface of CNT fiber through electrochemical deposition method. The CNT fiber/CuO NPs electrode was fabricated and applied to electrochemical non-enzymatic glucose sensor. Surface morphology and elemental composition of the CNT fiber/CuO NPs electrode was characterized by scanning electron microscope (SEM) with energy dispersive X-ray spectrometry (EDS). And its electrochemical characteristics were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The CNT fiber/CuO NPs electrode exhibited the good sensing performance for glucose detection such as high sensitivity, wide linear range, low detection limit and good selectivity due to synergetic effect of CNT fiber and CuO NPs. Based on the unique property of CNT fiber, CuO NPs were provide large surface area, enhanced electrocatalytic activity, efficient electron transport property. Therefore, it is expected to develop high performance flexible electrode materials using various nanomaterials.

• Journal of Sensor Science and Technology
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• v.14 no.5
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• pp.291-296
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• 2005

In this paper, the PDMS based micromixer having 3-dimension triangular structure has been developed for the reaction of samples in the micro volume. The mixing efficiency was measured according to the change of Reynolds number (Re: 0.08, 0.8, 8, 16) and channel height (100, 200, $300{\mu}m$). Total length of mixing region is 7.4 mm and the measured mixing efficiencies at the outlet were over 85 %. Within the mixing length 2.4 mm, the mixing efficiencies were more than 70 % at any Reynolds numbers, and this indicates the strong mixing has occurred inside the mixing channel due the triangular structures. By employing these 2 mixers, we have fabricated the microreactor to detect the glucose-catalysts reaction. The microreactor showed good reactivity of glucose and enzymes with the small amount of sample solution.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.22-34
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• 1998

The purpose of this study is to develop biosensor for determination of glucose, lactate, and ethanol in foods and food-stuffs simultaneously. The multiple cathode system was prepared with an oxygen electrode having one anode and hexagonal cathode. Glucose oxidase, mutarotase, lactate oxidase, alcohol oxidase and catalase were used for immobilization to determine glucose, lactate, and ethanol. These components including ethanol were simultaneously determined by the immobilized enzymes in the multiple cathode system. The determination of the components by enzyme sensor was based on the maximum slope of oxygen consumption from enzyme reaction of each sensor part. The response time for analysis was 1 min. The optimum condition for glucose, lactate and ethanol sensor was found to be 0.1 M potassium phosphate buffer, pH 7.0 at $40^{\circ}C$. Interferences of various sugars and organic acids were investigated. Less than 10% of error was found in determination of the components except organic acids. This difference was compensated by the modified equation. This system was confirmed by conventional methods. It was concluded that the multiple cathode system of this study is for an effective method to determine sugar, organic acid, ethanol simultaneously in foods.