• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.127-127
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• 2014

인체 내 소량의 생체성분(혈액, 소변 등)을 감지하는 바이오센서 기술은 질병 진단뿐만 아니라 예방 및 관리로 의료서비스 확대, 개인 맞춤형 진료 및 의료비 감소 효과를 가져올 수 있는 기술이다. 광바이오센서는 광학적인 측정방법을 이용하여 다양한 생화학물질들의 상호 반응을 검출해 낼 수 있는 바이오센서로 현재 활발하게 연구가 진행되고 있다. 광 바이오센서는 생체성분 내에 존재하는 전하를 가진 많은 이온들 및 Salt 농도 등에 영향을 받지 않기 때문에 나노 와이어를 이용한 FET (field-effect transistor)형 바이오센서에 비해 많은 장점을 가지고 있다. 일반적으로 광 바이오센서는 형광물질, 인광물질, 발색물질, 방사선 물질 등의 발광물질을 인식물질에 표지하여 인식물질과 분석물질과의 반응유무를 표지된 발광물질의 광학 신호를 감지하여 분석물질을 검출해내는 표지식 광 바이오센서 기술이 상용화되고 있다. 그러나 이러한 분석 방법은 민감도는 우수하지만 분석 시간이 매우 느리고, 고가의 분석 장비 및 복잡한 제조 공정 등의 단점들을 가지고 있다. 이러한 단점들을 극복하기 위하여 생화학 반응 유무를 표지물질 없이 광학적 방식으로 직접 측정할 수 있는 비표지식 광 바이오센서 기술이 최근 들어 많이 연구되고 있다. 본 논문에서는 광파장 이하의 주기를 가진 주기적 공진 격자 표면에서 일어나는 바이오 항원-항체 반응에 대한 공진 반사 파장을 측정하여 생체성분 내에 존재하는 바이오 항원을 고감도로 검출할 수 있는 비표지식 공진반사광 바이오센서 기술을 소개하고자 한다. 공진반사광 바이오센서를 이용하여 human serum내에 존재하는 심근경색 마커인 troponin I (cTnI), creatine kinase MB (CK-MB), myoglobin (MYO)을 0.1 ng/mL 이하의 농도까지 고감도로 측정할 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.182-186
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• 2006

This study was investigated on the antioxidative activity of $70\%$ ethanol extracts from lotus (Nelumbo nucifera) leaf. The extraction yields of $70\%$ ethanol extract was $8.16\%$. The extract was further fractionated subsequently by hexane, chloroform, ethyl acetate, butanol and water. Antioxidative activity was examined by electron donating ability (EDA) using DPPH, TBA value, acid value (AV), and peroxide value (POV), in comparison with commercial antioxidants. Butanol fraction showed the highest extraction yields but ethyl acetate fraction showed the highest phenol content. The ethyl acetate fraction showed the highest EDA. The antioxidative activity of ethyl acetate fraction determined by AV and POV in accelerated oxidation condition of lard was similar to that of BHA.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.534-538
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• 1991

A procedure for spectrophotometric determination of traces of boron in high-purity trichlorosilane (TCS) is proposed utilizing an adsorptive separation. NaCl is chosen as an Lewis base adsorbent which forms a complex with boron compounds in TCS, and is well dissolved in sulfuric acid-quinalizarin color-forming agent without causing an interference in colorimetric measurements. The proposed adsorptive separation method is free from the formation of silica gel and gas bubbles during the analysis of TCS. The method reveals that the boron concentration in a semiconductor grade TCS is 6.1 ${\mu}$g/l within the standard deviation of ${\pm}$20%. On the other hand, the boron concentration of the purified TCS which is separated from NaCl-boron compounds complex is reduced to 0.2 ${\mu}$g/l, showing the efficient applicability of NaCl to the adsorptive separation. The effectiveness of NaCl for the removal of boron in TCS purification is also described in comparison with other well-known adsorbents.

• Journal of the Korea Institute of Building Construction
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• v.24 no.3
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• pp.297-308
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• 2024

This study presents a novel approach for evaluating fire-induced damage depth in concrete. The methodology leverages the principle that exposure to high temperatures causes internal expansion within concrete, leading to increased voids and microcracks in the damaged zones. This heightened porosity results in greater absorption rates compared to undamaged areas. By immersing fire-damaged concrete samples in water and subsequently monitoring the drying process, the depth of damage can be assessed. Differences in drying rates and color variations between damaged and undamaged areas serve as visual indicators for determining the extent of the damage. Experimental results from this water immersion method revealed damage depths of 38.7mm and 37.5mm for two different concrete mixtures. These measurements notably surpass the damage depths estimated using traditional phenolphthalein-based methods. This discrepancy suggests that utilizing the absorption rate principle, which is directly linked to the physical changes caused by thermal expansion, offers a more accurate and sensitive assessment of fire damage depth compared to methods relying solely on the presence of Portlandite for colorimetric indication.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.419-424
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• 1998

An enzyme-linked immunosorbent assay (ELISA) was established for the detection of zearalenone by using monoclonal antibodies produced by Z-M-26 hybridoma cells when injected into a mouse and zearalenone-oxime-OV A conjugate. Zearalenone-oxime-OV A conjugates were diluted with carbonyl buffer, coated to 96 well microtiter plates at $4^{\circ}C$ overnight and blocked with 1% BSA overnight. One thousand times diluted antibody solution together with standard zearalenone or sample was added to 96-well microtiter plates and stood overnight. A secondary antibody conjugated with HRP was added and an hour later, enzyme substrate (TMBZ) solution was added for color develpment. Mter 30 minutes, coloring reaction was terminated by adding 2 N $H_2S0_4$ and the O.D. was measured at 450 nm. Detection range of this method was about 0.1~100 ppb. The established indirect competitive ELISA method was suitable for a rapid and effective analysis of zearalenone in agricultural products.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.111-117
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• 1991

We examined to develop the enzyme linked immunosorbent assay (ELISA) for determination of zearalenone in animal feeds. Zearalenone was first converted to 6'-(carboxymethyl) zearalenone oxime(zearalenone oxime) to get a coupling site and then conjugated to bovine serum albumin(BSA) for use as immunogen and to horseradish peroxidase(HRP) for use as enzyme marker. Antibody against zearalenone was obtained after 11 weeks of immunization of rabbit with zearalenone oxime-BSA. Cross reactivity of the antibody with ${\alpha}-zearalanol,\;{\beta}-zearalenol,\;{\alpha}-zearalanol\;and\;{\beta}-zearalanol$ were 168, 46, 26 and 20% respectiviely. A simple procedure was devised for the screening of zearalenone in feeds using ELISA. Feeds samples(5g) were extracted by blending with 25 ml of methanol-phospate butTered saline-dimethylformate(70 : 29 : 1) and the extract was filtered and aqueous filterate analyzed. It took only 1 hours to do whole procedure for the analysis of zearalenone in feeds by the direct competitive ELISA, and detectable limit was 1-100 ppb. Using this procedure, only 4 of 24 feed samples showed positive results with 3.93-7.43 ppb levels.

• Journal of the Korean Applied Science and Technology
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• v.38 no.5
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• pp.1273-1281
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• 2021

The purpose of this study was to increase the power of color and examine the long-lasting power, which is a disadvantage of one-pack acid hair dye by using chestnut shell pigment. For this, hair dyeing power was measured using a spectrophotometer, the optical density(O.D.) value was measured to examine the degree of fading of the hair, and the elasticity of the hair was analyzed by measuring the tensile strength. As a result of comparing the results of applying different leaving times and treatment methods to the hair samples of each level, the experimental group that was heat-treated for 20 minutes showed the highest dyeing power. Then, it was confirmed in the order of 40 minutes of natural exposure, 10 minutes of heat treatment, and 20 minutes of natural exposure. And it was also confirmed that the color expression visually improved as it went up to level 10. However, at level 10, it was confirmed that some water loss occurred even after 3 days and the tensile strength was low. These findings that indicated the beauty industry will popularize a one-step acid hair dye containing various natural dye ingredients to help maintain modern people's well-being and healthy mind and body.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.4
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• pp.401-410
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• 2016

Since the late 19th century, scientific logic and techniques have been used extensively in the field of clinical pathology, including many laboratory tests utilizing various apparatuses and instruments. Among the techniques to measure hemoglobin, the visual color comparison method was most popular around this time; the specific gravity method and gasometric method were not widely adopted. Instruments that use the visual color comparison method include Gowers' hemoglobinometer, von Fleischl's hemoglobinometer, Dare's hemoglobinometer, Oliver's hemoglobinometer, Haden-Hausser hemoglobinometer, and Spencer Hb meter. Initially, the visual color comparison methods were used to diluate and hemolyze blood with distilled water and then to measure its color. Later, these methods were further developed to measure hemoglobin without dilution, and improved with the formation of acid or alkaline hematin ensuring the stability of color development. Hammerschlag's method as well as the Schmaltz and Peiper's methods were based on specific gravity measurement, but they were not widely used. The gasometric method used the Van Slyke gasometer, indirectly measuring the hemoglobin concentration. This method provides the most accurate results. This survey examined the characteristics and limitations of hemoglobinometers and methods used to measure hemoglobin from the late 19th century to the early-and mid-20th century. Moreover, this study aims to improve the understanding and applicability of the current methods and emerging technologies used in measuring hemoglobin. It is also expected that this investigation is the starting point to promote awareness of the need to organize historical data for a variety of historical relics of the diagnostic laboratory tests.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.372-379
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• 1991

A rapid and simple quantitative assay method for aminoglycoside-3'- phosphotransferase (APH(3')) derived from E. coli ATCC 21990 was developed using the thin layer chromatographic densitometry, 3'-phosphorylated kanamycin B (3'-PKMB), product of APH (3') reaction, was separated from reaction mixtures by developing on the silica gel TLC plate with chloroform-methanol-ammonia water (3:4:3). The quantity of the 3'-PKMB was measured by densitometry after color development by ninhydrin method. Densitometric TLC assay for APH (3') was showed a good quantitative result and reproducibility. Sensitivity of this assay was 1.56 nmol of 3'-PKMB and could be analyzed many samples at same time. This method may be applicable for the analysis of inactivating enzymes of aminoglycoside antibiotics.

• KSBB Journal
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• v.24 no.5
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• pp.420-424
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• 2009

The present study was aimed for the fetor in the livestock facilities. Simple detection systems for ammonia and hydrogen sulfide were examined to see the mechanism making the discoloration length of malodorous substance concentration. Detector tube for ammonia showed a good linearity of 99.6% while hydrogen sulfide detector tube gave 99.7% linearity with reproductivity of 95%.