• Title, Summary, Keyword: biosensor

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Toxic Effect of Cadmium Assay in Contaminated Soil Earthworm Cell Using Modified Sensor

  • Ly, Suw Young;Kyung, Lee;Kim, Chae Hwa;Seo, Roma;Lee, Soo Youn;Kim, Lina;Chae, Su min;Choi, Sung Wook;Kim, Ji Yoon
    • Toxicological Research
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    • v.31 no.2
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    • pp.213-217
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    • 2015
  • A voltammetric toxic metal of cadmium detection was studied using a fluorine doped graphite pencil electrode (FPE) in a seawater electrolyte. In this study, square wave (SW) stripping and chronoamerometry were used for determination of Cd(II) in seawater. Affordable pencils and an auxiliary electrode were used as reference. All experiments in this study could be performed at reasonable cost by using graphite pencil. The application was performed on the tissue of contaminated soil earthworm. The results show that the method can be applicable for vegetables and in vivo fluid or medicinal diagnosis.

Biosensor의 원리와 응용

  • 김병홍
    • The Microorganisms and Industry
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    • v.16 no.1
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    • pp.28-39
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    • 1990
  • Biosensor는 모든 종류에서 공히 생체물질로 이루어지는 감지 부분, transducer 그리고 전자부분으로 이루어진다. 따라서 Biosensor는 사용하는 생체물질, transducer로 그리고 측정되는 물질에 따라 분류된다. Biosensor에 이용될 수 있는 생물반응은 pH 변화, ion 생산및 소비, 기체생산및 소비, 발열, 발광, 전자전달, 질량변화 등을 들 수 있다. 이상의 반응을 유발하는 생체물질은 효소, 항체등 단백질과 세포, 조직등 다양하다. 여기에서는 transducer의 특징을 먼저 살펴보고 biosensor 각론에서 이들 생체물질의 반응 특징을 소개한다.

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Electronic Detection of Biomarkers by Si Field-Effect Transistor from Undiluted Sample Solutions with High Ionic Strengths

  • Ah, Chil-Seong;Kim, An-Soon;Kim, Wan-Joong;Park, Chan-Woo;Ahn, Chang-Geun;Yang, Jong-Heon;Baek, In-Bok;Kim, Tae-Youb;Sung, Gun-Yong
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1561-1567
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    • 2010
  • In this study, we have developed a new detection method using Si field effect transistor (FET)-type biosensors, which enables the direct monitoring of antigen-antibody binding within very high-ionic-strength solutions such as 1$\times$PBS and human serum. In the new method, as no additional dilution or desalting processes are required, the FET-type biosensors can be more suitable for ultrasensitive and real-time analysis of raw sample solutions. The new detection scheme is based on the observation that the strength of antigen-antibody-specific binding is significantly influenced by the ionic strength of the reaction solutions. For a prostate specific antigen (PSA), in some conditions, the binding reaction between PSA and anti-PSA in a low-ionic strength reaction solution such as 10 ${\mu}M$ phosphate buffer is weak (reversible), while that in high-ionic strength reaction solutions such as 1$\times$PBS or human serum is strong.

Development of a Fiber-Optic Biosensor for the Detection of Listeria monocytogenes (리스테리아 식중독균 검출을 위한 광학식 바이오센서 개발)

  • Kim G.;Choi K.H.
    • Journal of Biosystems Engineering
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    • v.31 no.2
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    • pp.128-134
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    • 2006
  • Frequent outbreaks of foodborne illness demand the need for rapid and sensitive methods for detection of these pathogens. Recent development of biosensor technology has a great potential to meet the need for rapid and sensitive pathogens detection from foods. An antibody-based fiber-optic biosensor and an automated reagents supply system to detect Listeria monocytogenes were developed. The biosensor for detection of Listeria monocytogenes in PBS and bacteria spiked food samples was evaluated. The automated reagents supply system eliminated cumbersome sample and detection antibody injection procedures that had been done manually. The biosensor could detect $10^4$ cfu/ml of Listeria monocytogenes in PBS. By using the fiber-optic biosensor, $2x10^8$ cfu/ml of Listeria monocytogenes in the food samples were detectable.

Characterization and Food Application of a Potentiometric Biosensor Measuring $\beta$-Lactam Antibiotics

  • Park, In-Seon;Kim, Dong-Kyung;Kim, Nam-Soo
    • Journal of Microbiology and Biotechnology
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    • v.14 no.4
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    • pp.698-706
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    • 2004
  • $\beta$-Lactam antibiotics such as penicillin G, amoxicillin, and ampicillin were determined by a potentiometric biosensor system which exploited penicillinase immobilized on Immobilon cellulose nitrate membrane and a flat-bottomed pH electrode-as the biological component and transducer. The optimum reaction buffer for maximum sensitivity was found as 2 mM of sodium phosphate buffer (pH 7.2). The detection limit of the biosensor could be extended to 1 $\mu{M}$ of the analytes by increasing the enzyme loading for immobilization to 100 units/$m\ell$. The model samples spiked with each of the standard penicillins were measured for their biosensor responses and HPLC peak area, resulting in the relative responses of 82.1-103.5% and 79.5-106.1% for the biosensor method along with HPLC analysis, respectively. This result showed a good precision of the current biosensor method for screening the penicillin compounds.

Detection of Streptavidin-Biotin Complexes Using a Highly Sensitive AlGaN/GaN-Based Extended-Gate MISHEMT-Type Biosensor

  • Lee, Hee Ho;Bae, Myunghan;Choi, Byoung-Soo;Shin, Jang-Kyoo
    • Journal of Sensor Science and Technology
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    • v.25 no.5
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    • pp.320-325
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    • 2016
  • In this paper, we propose an AlGaN/GaN-based extended-gate metal-insulator-semiconductor high electron mobility transistor (MISHEMT)-type biosensor for detecting streptavidin-biotin complexes. We measure the drain current of the fabricated sensor, which varies depending on the antibody-antigen reaction of streptavidin with biotin molecules. To confirm the immobilization of biotin polyethylene glycol (PEG) thiol, we analyze the Au surface of a GaN sample using X-ray photoelectron spectroscopy (XPS). The proposed biosensor shows higher sensitivity than Si-based extended-gate metal oxide semiconductor field effect transistor (MOSFET)-type biosensor. In addition, the proposed AlGaN/GaN-based extended-gate MISHEMT-type biosensor exhibits better long-term stability, compared to the conventional AlGaN/GaN-based MISHEMT-type biosensor.

A Compact Tunable VCSEL and a Built-in Wavelength Meter for a Portable Optical Resonant Reflection Biosensor Reader

  • Ko, Hyun-Sung;Kim, Bong-Kyu;Kim, Kyung-Hyun;Huh, Chul;Kim, Wan-Joong;Hong, Jong-Cheol;Park, Seon-Hee;Yang, Seong-Seok;Jang, Ho-Jin;Sung, Gun-Yong
    • Journal of the Optical Society of Korea
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    • v.14 no.4
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    • pp.395-402
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    • 2010
  • This study reports a portable and precision photonic biosensor reader that can measure the concentration of a particular antigen using an optical resonant reflection biosensor (ORRB). To create a compact biosensor reader, a compact tunable vertical-cavity surface-emitting laser (VCSEL) and a compact built-in wavelength meter were manufactured. The wavelength stability and accuracy of the compact built-in wavelength meter were measured to be less than 0.02 nm and 0.06 nm, respectively. The tunable VCSEL emission wavelength was measured with the compact built-in wavelength meter, it has a fast sweep time (~ 10 seconds) and a wide tuning range (> 4 nm) that are sufficient for biosensor applications based on ORRB. The reflection spectrum of a plastic based ORRB chip was measured by the fabricated portable photonic biosensor reader using the VCSEL and wavelength meter. Although the reader is the size of a palmtop device, it could make a precise measurement of the peak wavelength on equal terms with a conventional bulky optical spectrometer.

Replication of label-free biosensor with nano grating structures (나노 그래이팅 구조를 갖는 비표지식 바이오센서 성형에 관한 연구)

  • Cho, E.H.;Kim, B.W.;Choi, S.W.;Kim, K.H.;Sung, G.Y.;Kang, S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • pp.290-293
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    • 2009
  • This paper presents the development of a disposable label-free biosensor for bio molecular interaction analysis. Label-free biosensors have advantages of high performance in sensitivity and short detection time. Among various label-free systems, we introduced biosensor with nano grating structures based on white light source and spectrometer. And to develop high efficiency label-free biosensor, we suggest replicating processes satisfying required specification. We also report a system set-up to evaluate the characteristics of phenomenon shown in this biosensor system.

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Fabrication of enzymatic biosensor based on the poly(3-thiophenecarboxylic acid-co-thiophene) polymer as electron-transfer materials

  • Kim, Soo-Yeoun;Jo, Hyeon-Jin;Choi, Seong-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.269-278
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    • 2019
  • We fabricated glucose oxidase (GOx)-modified biosensor for detection of glucose by physical immobilization of GOx after electrochemical polymerization of the conductive mixture monomers of the 3-thiophenecarboxylic acid (TCA) and thiophene (Th) onto ITO electrode in this study. We confirmed the successfully fabrication of GOx-modified biosensor via FT-IR spectroscopy, SEM, contact angle, and cyclic voltammetry. The fabricated biosensor has the detection limit of $0.1{\mu}M$, the linearity of 0.001-27 mM, and sensitivity of $38.75mAM^{-1}cm^{-2}$, respectively. The fabricated biosensor exhibits high interference effects to dopamine, ascorbic acid, and L-cysteine, respectively. From these results, the fabricated GOx-modified biosensor with long linearity and high sensitivity could be used as glucose sensor in human blood sample.