• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.159-164
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• 2021

As the attachable-type wearable devices have received considerable interests, the need for the development of high-performance electrode materials of fabric or textiles type is emerging. In this study, we demonstrated the electrochemical property of CNT fibers electrode as a flexible electrode material and its non-enzymatic glucose sensing performance. Surface morphology of CNT fibers was observed by SEM. And the electrochemical characteristics were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The CNT fibers based sensor exhibited improved sensing performances such as high sensitivity, a wide linear range, and low detection limit due to improved electrochemical properties such as low capacitive current, good electrochemical activity by efficient direct electron transfer between the redox species and the electrode interface. Therefore, this study is expected to be used as a basic research for the development of high performance flexible electrode materials based on CNT fibers.

• Journal of Sensor Science and Technology
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• v.25 no.6
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• pp.435-439
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• 2016

We report a novel detection technology for glycated hemoglobin (HbA1c) that is measured primarily to identify the three-month average plasma glucose concentration. In enzymatic measuring of glycated hemoglobin, the generated hydrogen peroxide was then used as a reducing agent of gold (III) for the synthesis of gold (0). Gold nanoparticles obtained from this novel approach were measured by optical and piezoelectric methods. In optical method, we have developed polymer based film-type sensor cartridge filled with all the reagents for glycated hemoglobin analysis and the cartridge worked very well having the detection limit of 0.53% of glycated hemoglobin. On the other hand, quartz crystal microbalance (QCM) sensors also have been developed to determine the abilities of surface modified QCM sensors at various levels of the concentration of glycated hemoglobin to bind gold nanoparticles and limit of detection was 0.90%. Finally, despite of relatively lower sensitivities of QCM sensor and film-type optical sensor than well-plate based optical detection, these two sensors were available to measure the glycated hemoglobin level for diabetes patients and normal person.

• 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 Veterinary Science
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• v.24 no.5
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• pp.70.1-70.14
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• 2023

Background: Mycobacterium avium subspecies paratuberculosis (MAP) causes a chronic and progressive granulomatous enteritis and economic losses in dairy cattle in subclinical stages. Subclinical infection in cattle can be detected using serum MAP antibody enzyme-linked immunosorbent assay (ELISA) and fecal polymerase chain reaction (PCR) tests. Objectives: To investigate the differences in blood parameters, according to the detection of MAP using serum antibody ELISA and fecal PCR tests. Methods: We divided 33 subclinically infected adult cattle into three groups: seronegative and fecal-positive (SNFP, n = 5), seropositive and fecal-negative (SPFN, n = 10), and seropositive and fecal-positive (SPFP, n = 18). Hematological and serum biochemical analyses were performed. Results: Although the cows were clinically healthy without any manifestations, the SNFP and SPFP groups had higher platelet counts, mean platelet volumes, plateletcrit, lactate dehydrogenase levels, lactate levels, and calcium levels but lower mean corpuscular volume concentration than the SPFN group (p < 0.017). The red blood cell count, hematocrit, monocyte count, glucose level, and calprotectin level were different according to the detection method (p < 0.05). The SNFP and SPFP groups had higher red blood cell counts, hematocrit and calprotectin levels, but lower monocyte counts and glucose levels than the SPFN group, although there were no significant differences (p > 0.017). Conclusions: The cows with fecal-positive MAP status had different blood parameters from those with fecal-negative MAP status, although they were subclinically infected. These findings provide new insights into understanding the mechanism of MAP infection in subclinically infected cattle.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.1 s.53
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• pp.114-119
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• 2005

The study was carried out to develope quantitative analysis method of individual sugars in licorice extract. Individual sugars were analyzed by HPLC equipped with Refractive Index(RI) Detector. R values of sucrose and glucose were 1.0000 and R values of fructose and maltose were 0.9999. Standard calibration curve showed good linearity. Detection limit of sugars was in the range of 1.58 to 3.92 ${\mu}g$. Recovery rate of fructose, glucose, sucrose and maltose was $99.4\~102.2\%,\;92.3\~97.9\%,\;99.4\~102.0\%,\;91.1\~101.0$ respectively. Measure uncertainty was calculated to confirm trust and accuracy of analytical results. Main uncertainty factors were standard purity and HPLC replication injection. In $95\%$ trust level expanded uncertainty of sugars in licorice extract were fructose $1.98\pm0.047,\;glucose\;1.32\pm0.065,\;sucrose\;11.69\pm1.177,\;maltose\;1.06\pm0.042\;g/100\;g$.

• Journal of Korean Academy of Nursing
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• v.37 no.4
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• pp.453-458
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• 2007

Purpose: The purpose of this study was to compare metabolic syndrome (MS) risk factor prevalence by obesity and age in middle-aged women. Method: Two hundred and fifty-one subjects were recruited from the health promotion center of a tertiary care hospital in an urban city. MS was defined by the third report of the national cholesterol education program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults(Adult Treatment Panel III)(ATP III), and obesity was determined by body mass $index(BMI){\geq}25kg/m^2$. Results: The mean blood pressure, fasting glucose, total cholesterol, and triglyceride were significantly higher in the obese group than in the non-obese group. The prevalence of MS, hypertension, and impaired fasting glucose were significantly higher in the obese group than in the non-obese group. In the forties, blood pressure was significantly higher in the obese group than in the non-obese group. In the fifties, body fat, systolic blood pressure, fasting glucose, total cholesterol, and triglyceride were significantly higher in the obese group than in the non-obese group. Conclusions: These results show that the nurse should focus on the obese fifty year old female patients for improvement of the MS risk factors.

• Journal of Electrochemical Science and Technology
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• v.2 no.2
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• pp.124-129
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• 2011

A simple process of fabricating micropillar structure and its influence upon enhancing electrochemical biosensor response were studied in this work. Conducting polymer PEDOT was used as a base material in formulating a composite with PVA. Micro porous PC membrane filter was used as a template for the micropillar of the composite on ITO electrode. This structure could provide plenty of encapsulating space for enzyme species. After dosing enzyme solution into this space, Nafion film tent was cast over the pillar structure to complete the micropillar cavity structure. In this way, the encapsulation of enzyme could be accomplished without any chemical modification. The amount of enzyme species was easily controllable by varying the concentration of the dosing solution. The more amount of enzyme is stored in the sensor, the higher the electrochemical response is produced. One more reason for the sensitivity improvement comes from the large surface area of the micropillar structure. Application of 0.7 V produced the best current response under the condition of pH 7.4. This biosensor showed linear response to the glucose in 0.1~1 mM range with the average sensitivity of $14.06{\mu}A/mMcm^2$. Detection limit was 0.01 mM based on S/N = 3.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2121-2124
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• 2004

전기화학발광(ECL) 시스템은 높은 감도와 넓은 선형동작영역을 가지므로 분석화학에서 넓게 연구 되고 있다. 그러나 포토멀티플러, 광섬유와 플루오르메터로 구성된 ECL 검출 시스템은 크기가 크고, 전력소모가 많으며, 고가인 단점이 있다. 따라서 이러한 단점을 보완하기 위해 p+n 포토다이오드를 이용한 마이크로 ECL시스템을 제작 과산화수소 농도를 50uM${\sim}$10mM 범위에서 측정하였고, 글루코오스는 1mM${\sim}$20mM 농도범위에서 측정하였다. 따라서 마이크로 ECL 시스템이 바이오센서 혹은 바이오 분석기로써의 가능성을 확인 하였다.

• Journal of Astronomy and Space Sciences
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• v.35 no.2
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• pp.111-117
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• 2018

A previous exo-terrestrial life-detecting experiment, which was conducted on Mars, sought to detect the products of glucose metabolism, the most common biological process on Earth (Viking biological experiment). Today, glucose metabolism is not considered the universal process of life survival. As NASA plans to launch an orbiter mission in the near future (2020s, the Clipper) and ultimately conduct a lander mission on Europa, a detection experiment that can give broader information regarding habitability is highly required. In this study, we designed a life-detecting experiment using a more universal feature of life, the amphipathic molecular membrane, theoretically considering the environment of Europa (waterdominant environment). This designed experiment focuses on finding and profiling hydrophobic cellular membrane-like microstructures. Expected results are given by conceptual data analysis with plausible hypothetical samples.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.39-45
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• 2002

Clinical application of positron emission tomography (PET) is rapidly increasing for the defection and staging of cancer at whole-body studios performed with the glucose analogue tracer 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG). Although FDG PET cannot match the anatomic resolution of conventional imaging techniques in the liver and the other abdominal organs, it is particularly useful for identification and characterization of the entire body simultaneously. FDG PET can show foci of metastatic disease that may not be apparent at conventional anatomic imaging and can aid in the characterizing of indeterminate soft-tissue masses. Most abdominal cancer requires surgical management. FDG PET can improve the selection of patients for surgical treatment and thereby reduce the morbidity and mortality associated with inappropriate surgery. FDG PET is also useful for the early detection of recurrence and the monitoring of therapeutic effect. The abdominal cancers, such as gastroesophageal cancer, colorectal cancer, liver cancer and pancreatic cancer, are common malignancies in Korea, and PET is one of the most promising and useful methodologies for the management of abdominal cancers.