• Title, Summary, Keyword: biosensor

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Rapid Detection of Salmonella enteritidis in Pork Samples with Impedimetric Biosensor: Effect of Electrode Spacing on Sensitivity

  • Kim, Gi-Young;Moon, Ji-Hea;Hahm, Bung-Kwon;Morgan, Mark;Bhunia, Arun;Om, Ae-Son
    • Food Science and Biotechnology
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    • v.18 no.1
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    • pp.89-94
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    • 2009
  • Frequent outbreaks of foodborne illness have been increasing the awareness of food safety. Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Some immunological, rapid assays are developed, but these assays still require prolonged enrichment steps. Recently developed biosensors have shown potential for the rapid detection of foodborne pathogens. In this study, an impedimetric biosensor was developed for rapid detection of Salmonella entritidis in food sample. To develop the biosensor, an interdigitated microelectrode (IME) was fabricated by using a semiconductor fabrication process. Anti-Salmonella antibodies were immobilized based on neutravidin-biotin binding on the surface of the IME to form an active sensing layer. To evaluate the effect of electrode gap on sensitivity of the sensor, 3 types of sensors with different electrode gap sizes (2, 5, and $10{\mu}m$) were fabricated and tested. The impedimetric biosensor could detect $10^3\;CFU/mL$ of Salmonella in pork meat extract with an incubation time of 5 min. This method may provide a simple, rapid, and sensitive method to detect foodborne pathogens.

Development, Validation, and Application of a Portable SPR Biosensor for the Direct Detection of Insecticide Residues

  • Yang, Gil-Mo;Cho, Nam-Hong
    • Food Science and Biotechnology
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    • v.17 no.5
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    • pp.1038-1046
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    • 2008
  • This study was carried out to develop a small-sized biosensor based on surface plasmon resonance (SPR) for the rapid identification of insecticide residues for food safety. The SPR biosensor module consists of a single 770 nm-light emitting diodes (LED) light source, several optical lenses for transferring light, a hemisphere sensor chip, photo detector, A/D converter, power source, and software for signal processing using a computer. Except for the computer, the size and weight of the sensor module are 150 (L)$\times$70 (W)$\times$120 (H) mm and 828 g, respectively. Validation and application procedures were designed to assess refractive index analysis, affinity properties, sensitivity, linearity, limits of detection, and robustness which includes an analysis of baseline stability and reproducibility of ligand immobilization using carbamate (carbofuran and carbaryl) and organophosphate (cadusafos, ethoprofos, and chlorpyrifos) insecticide residues. With direct binding analysis, insecticide residues were detected at less than the minimum 0.01 ppm and analyzed in less than 100 sec with a good linear relationship. Based on these results, we find that the binding interaction with active target groups in enzymes using the miniaturized SPR biosensor could detect low concentrations which satisfy the maximum residue limits for pesticide tolerance in Korea, Japan, and the USA.

Sensitivity Alterable Biosensor Based on Gated Lateral BJT for CRP Detection

  • Yuan, Heng;Kang, Byoung-Ho;Lee, Jae-Sung;Jeong, Hyun-Min;Yeom, Se-Hyuk;Kim, Kyu-Jin;Kwon, Dae-Hyuk;Kang, Shin-Won
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.1
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    • pp.1-7
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    • 2013
  • In this paper, a biosensor based on a gated lateral bipolar junction transistor (BJT) is proposed. The gated lateral BJT can function as both a metal-oxide-semiconductor field-effect transistor (MOSFET) and a BJT. By using the self-assembled monolayer (SAM) method, the C-reactive protein antibodies were immobilized on the floating gate of the device as the sensing membrane. Through the experiments, the characteristics of the biosensor were analyzed in this study. According to the results, it is indicated that the gated lateral BJT device can be successfully applied as a biosensor. Additionally, we found that the sensitivity of the gated lateral BJT can be varied by adjusting the emitter (source) bias.

Interfacial Engineering of Graphenes for Energy and Biosensor Devices

  • Park, H.S.
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.12-12
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    • 2011
  • Interfacing functional materials with electrical or biological systems is of prime importance in terms of expanding applicative fields and obtaining high performances of devices. Herein, I report the functionalization of graphenes through supramolecular assembly and their electrochemical applications into fuel cells, supercapacitors, and biosensor devices. The solution processable nanohybridization of graphenes by functional materials such as ionic liquids, polyelectrolytes, block copolymers, and biomaterials, described herein would pave the way to obtain high performances of flexible energy and biosensor devices as well as to overcome the existing technology barriers.

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Performances of Point-of-care Testing Systems for HDL Cholesterol

  • Chae, Woo-Churl;Cho, Jeoung-Hwan;Paek, Se-Hwan
    • 한국생물공학회:학술대회논문집
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    • pp.201-204
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    • 2003
  • Plasma lipoproteins transporting cholesterol through blood vessels are divided into three major classes, VLDL, LDL, and HDL. The ratio of HDL cholesterol over the total can be used as an indicator for prognosis of coronary artery diseases. In this study, we have developed two analytical systems for %HDL cholesterol with different flow modes toward gravity and analyzed them for their characteristics and performances.

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The Eukaryote Alternative: Advantages of Using Yeasts in Place of Bacteria in Microbial Biosensor Development

  • Walmsley, Richard M.;Keenan, Patrick
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.6
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    • pp.387-394
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    • 2000
  • The relationship between Man and yeast has been a successful and enduring one. The characteristics of yeast have made it an ideal tool in scientific research and as such, it has been used extensively. In this review some of the advantages, methods and applications of yeasts in the biosensor field are outlined. In doing so, we propose a eukaryotic alternative to the current battery of bacteria-based microbial biosensors.

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Shuffled toluene-o-xylene monooxygenase를 이용한 TCE 측정용 fluorescence biosensor

  • ;;;;Thomas Wood
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.475-478
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    • 2003
  • A sol-gel fiber-optic biosensor with encapsulated pH-sensitive fluorophore and immobilized genetically modified toluene-o-xylene monooxygenase was developed to detect TCE, which is carcinogenic chlorinate organic compounds prevailing in ground water. The sensitivity was characterized for the composition of sol-gel, and manufacturing procedure.

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Measurement of Glucose Concentration Using a μFIA Biosensor (μFIA 바이오 센서를 이용한 포도당 농도 측정)

  • ;Joseph Irudayaraj
    • Journal of Biosystems Engineering
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    • v.28 no.5
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    • pp.465-468
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    • 2003
  • A microdialysis coupled flow injection amperometric biosensor was calibrated to measure the concentration of glucose using 7 standard samples from 10ml to 70ml of glucose solution. The output of the sensor increased linearly with an increase in the glucose concentration with an $R^2$ correlation of 0.99. The amperometric biosensor was then applied to measure the. glucose concentration of 2 commercial samples(Orange and Pineapple juice) and the results compared with HPLC. Around 12% error was observed in glucose concentration measurements of the samples analyzed. The sensor has potential in rapid measurement once the calibration is done. Potential for on-line sensing is also discussed.

Detection of Avian Influenza-DNA Hybridization Using Wavelength-scanning Surface Plasmon Resonance Biosensor

  • Kim, Shin-Ae;Kim, Sung-June;Lee, Sang-Hun;Park, Tai-Hyun;Byun, Kyung-Min;Kim, Sung-Guk;Shuler, Michael L.
    • Journal of the Optical Society of Korea
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    • v.13 no.3
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    • pp.392-397
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    • 2009
  • We designed a wavelength interrogation-based surface plasmon resonance (SPR) biosensor to detect avian influenza DNA (AI-DNA). Hybridization reactions between target AI-DNA probes and capture probes immobilized on a gold surface were monitored quantitatively by measuring the resonance wavelength in the visible waveband. The experimental results were consistent with numerical calculations. Although the SPR detection technique does not require the DNA to be labeled, we also evaluated fluorescently-labeled targets to verify the hybridization behavior of the AI-DNA. Changes in resonance were found to be linearly proportional to the amount of bound analyte. A wavelength interrogation-type SPR biosensor can be used for rapid measurement and high-throughput detection of highly pathogenic AI viruses.

Flow Injection Biosensor for the Detection of Anti-Cholinesterases

  • Chung, Myung-Sun;Lee, Yong-Tae;Lee, Hye-Sung
    • BMB Reports
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    • v.31 no.3
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    • pp.296-302
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    • 1998
  • A potentiometric flow injection biosensor for the analysis of anti-cholinesterases (anti-ChEs), based on inhibition of enzyme activity, was developed. The sensor system consists of a reactor with acetylcholinesterase (AChE) immobilized on controlled pore glass and a detector with an $H^{+}-selective$ PVC-based membrane electrode. The principle of the analysis is based on the fact that the degree of inhibition of AChE by an anti-ChE is dependent on the concentration of the anti-ChE in contact with AChE. The sensor system was optimized by changing systematically the operating parameters of the sensor to evaluate the effect of the changes on sensor response to ACh. The optimized biosensor was applied to the analysis of paraoxon, an organophosphorus pesticide. Treatment of the inhibited enzyme with pyridine-2-aldoxime fully restored the enzyme activity allowing repeated use of the sensor.

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