• Title/Summary/Keyword: glucose determination

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Application of cabbage Peroxidase for Glucose Assay (양배추 Peroxidase의 포도당 분석에의 이용)

  • Park, In-Shik;Kho, Sun-Ok;Nam, in
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.19 no.3
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    • pp.224-228
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    • 1990
  • Cabbage contained high peroxidase activity among tested plant sources. The cabbage peroxi-dase can replace horseradish peroxidase to assay glucose with glucose oxidase. The amount of glucose can be determined quantitatively by glucose oxidase-cabbage peroxidase. The opti-mum pH and temperature for enzymatic glucose determination by glucose oxidase-cabbage peroxidase were 6.0 and 35-45$^{\circ}C$ respectively. The glucose assay was inhibited by addition of various metal salts such as mercuric chloride lead acetate silver nitrate ammonium molyb-date sodium tunstate and cupric sulfate. The relationship between absorbance and amount of glucose was linear up to 8.33 mM glucose in the assay mixture under the assay conditions.

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Structure Determination of Sucrose by Acetylation and Acid Hydrolysis

  • Min, Hee-Jeong;Lee, Tae-Seong;Bae, Young-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.2
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    • pp.183-192
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    • 2014
  • For the structure determination of D-(+)-sucrose, which consists of ${\alpha}$-D-(+)-glucose and ${\beta}$-D-(+)-fructose, it was acetylated with acetic anhydride and triethyl amine, pyridine, zinc chloride, and sodium acetate as catalysts. The acetylated D-(+)-sucrose was acid-hydrolyzed using sulfuric acid and sodium chloride in methanolic solution. The structures of the reaction products were determined by $^1H$-NMR and $^{13}C$-NMR spectra. The yield of the acetylation indicated the high value in zinc chloride as 70% in zinc chloride catalyst. The acid-hydrolyzed product of the acetylated D-(+)-sucrose, 2,3,4,6,1',3',4',6'-octa-O-acetyl-D-(+)-sucrose, gave 2,3,4,6-tetra-O-acetyl-${\beta}$-D-(+)-glucose and it suggests that the acetylated D-(+)-sucrose was rearranged through the formation of oxonium ion by mutarotation in the 2,3,4,6-tetra-O-acetyl-${\alpha}$-D-(+)-glucose moiety and through the ring opening in the 1',3',4',6'-tetra-O-acetyl-${\beta}$-D-(+)-fructose moiety.

Determination of Insulin Signaling Pathways in Hepatocytes

  • Kim, Sang-Kyum
    • Toxicological Research
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    • v.21 no.3
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    • pp.195-208
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    • 2005
  • Diabetes is a major cause of morbidity and mortality, and associated with a high risk of atherosclerosis, and liver, kidney, nerve and tissue damage. Defective insulin secretion in pancreas and/or insulin resistance in peripheral tissues is a central component of diabetes. It is well established that, regardless of the degree of muscle insulin resistance, glucose levels in diabetic and non-diabetic individuals are determined by the rate of hepatic glucose production. Moreover recently studies using liver-specific insulin receptor knockout mice show the paramount role of the liver in insulin resistance and diabetes. Insulin exerts a multifaceted and highly integrated series of actions via its intracellular signaling systems. The first major section of this review defines the major insulin-mediated signaling pathways including phosphatidylinositol 3-kinase and mitogen activated protein kinases. The second major section of the review presents a summary and evaluation of methods for determination of the role and function of signaling pathways, including methods for determination of kinase phosphorylation, the use of pharmacological inhibitors of kinase and dominant-negative kinase constructs, and the application of new RNA interference methods.

Development of Glucose Biosensor Using Sol-Gel Reaction of Tetraethoxysilane (Tetraethoxysilane의 졸-겔 반응을 이용한 전기화학적 glucose biosenor 개발)

  • Chang, Seong-Cheol;Park, Deog-Su
    • Journal of Sensor Science and Technology
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    • v.21 no.4
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    • pp.311-317
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    • 2012
  • Disposable amperometric screen-printed biosensor strips have been fabricated by a sol-gel encapsulation for the analysis of glucose. The glucose oxidase(GOx) is entrapped in the gel matrix through sol-gel transition of tetraethoxysliane(TEOS). The biosensor is fabricated by GOx containing thin film of TEOS gel on the surface of screen-printed carbon electrode(SPCE). The GOx-containing thin film of TEOS gel offers a one-step modification process on the surface of SPCE. The optimum conditions for glucose determination have been characterized with respect to the applied potential, enzyme loading ratio, and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 16.0 mM and 0.25 mM, respectively.

Non-invasive Blood Glucose Measurement by a Portable Near Infrared (NIR) System (휴대용 근적외선 분광분석기를 이용한 비침투 혈당 측정)

  • 강나루;우영아;차봉수;이현철;김효진
    • YAKHAK HOEJI
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    • v.46 no.5
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    • pp.331-336
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    • 2002
  • The purpose of this study is to develop a non-invasive blood glucose measurement method by a portable near infrared (NIR) system which was newly integrated by our lab. The portable NIR system includes a tungsten halogen lamp, a specialized reflectance fiber optic probe and a photo diode array type InGaAs detector; which was developed by a microchip technology based on the lithography. Reflectance NIR spectra of different parts of human body (finger tip, earlobe, and inner lip) were recorded by using a fiber optic probe. The spectra were collected over the spectral range 1100 ∼ 1740 nm. Partial least squares regression (PLSR) was applied for the calibration and validation for the determination of blood glucose. The calibration model from earlobe spectra presented better results, showing good correlation with a glucose oxidase method which is a mostly used standard method. This model predicted the glucose concentration for validation set with a SEP of 33 mg/dL. This study indicated the feasibility for non-invasive monitoring of blood glucose by a portable near infrared system.

Assay of Glucose-6-phosphate Dehydrogenase in E. coli Cells Ruptured by Phage Ghost (Phage Ghost로 破裂시킨 E. coli 에서 Glucose-6-phosphate Dehydrogenase의 活性度 測定)

  • Yun, Se-Joong
    • Journal of the Korean Chemical Society
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    • v.12 no.4
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    • pp.142-145
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    • 1968
  • The relative activity of glucose-6-phosphate dehydrogenase in E. coli was measured at 340 $m\mu$ with a spectrophotometer. The synchronized E. coli cells in exponential phase were treated with Phage($T_2$) ghost, and used as a enzyme solution directly. This assay method supposed to be useful for the continuous determination of enzyme activity in E. coli.

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Fabrication of Polyimide Film Electrode by Laser Ablation and Application for Electrochemical Glucose Biosensor (Laser ablation을 이용한 폴리이미드 필름 전극제조 및 전기화학적 글루코오즈 바이오센서 응용)

  • Park, Deog-Su
    • Journal of Sensor Science and Technology
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    • v.22 no.5
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    • pp.357-363
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    • 2013
  • An ultraviolet pulsed laser ablation of polyimide film coated with platinum has been used to enhance the sensitivity for the application as an electrochemical biosensor. Densely packed cones are formed on polyimide surface after UV irradiation which results in increase of surface area. In order to apply the sensitivity improvement of laser ablated polyimide film electrodes, the glucose oxidase modified biosensor was fabricated by using an encapsulation in the gel matrix through sol-gel transition of tetraethoxysliane on the surface of laser ablated polyimide film. The optimum conditions for glucose determination have been characterized with respect to the applied potential and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 18.0 mM and 0.18 mM, respectively. The sensitivity of glucose biosensors fabricated with laser ablated polyimide film is about three times higher than that of plain polyimide film due to increase in surface area by laser ablation.

Fundamental Investigation of Non-invasive Determination of Glucose by Near Infrared Spectrophotometry (근적외선 분광법을 이용한 비침투적 혈당 분석법 개발에 관한 기초 연구)

  • Kim, Hyo J.;Woo, Young A.;Chang, Soo H.;Cho, Chang H.;Cantrell, Kevin;Piepmeier, Edward H.
    • Analytical Science and Technology
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    • v.11 no.1
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    • pp.47-53
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    • 1998
  • This study is to improve the diagnosis of diabetes mellitus and the self-monitoring of blood glucose in people with diabetes by providing a non-invasive method of monitoring blood glucose. A near-infrared (NIR) spectrophotometer was used to measure absorption spectra of 80 glucose samples ranges from 1 mg/dL to 200 mg/dL, and shows the standard error of prediction 1.8 mg/dL. Also, to investigate the effect of interference in blood, NaCl and sand were added in glucose and found the standard error of prediction of 2.8 mg/dL and 3.8 mg/dL, respectively. A new and more accurate calibration system for the spectrophotometer was developed from systematic study of light scattering, which cause nonlinear spectrophotometer response.

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