• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.373-377
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• 2003

Various groups of industrial and agricultural pollutants (heavy metal ions, cyanides, and pesticides) can be detected by enzymes. Since heavy metal ions inhibit urease, cyanides inhibit peroxidase, organophosphorus and carbamate pesticides inhibit butyrylcholinesterase, these enzymes were co-immobilized into a bovine serum albumin gel on the surface of an ion-sensitive field effect transistor to create a bioprobe that is sensitive to the compounds mentioned above. The sensitivity of the present sensor towards KCN corresponded to $1\;\mu\textrm{M}$ with 1 min of incubation time. The detection limits for Hg(II) ions and the pesticide carbofuran were 0.1 and $0.5\;\mu\textrm{M}$, respectively, when a 10 min sensor incubation time in contaminated samples was chosen. The total time for determining the concentrations of all species mentioned did not exceed 20 min.

• Journal of Microbiology
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• v.35 no.2
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• pp.87-91
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• 1997

Monoclonal antibodies were prepared in order to an assay method for Vibrio vulnificus. Sixteen mouse ybridoma cell lines were established by immunization of whole cell antigen to BALB/c mice, fusion with SP2/O myeloma cells, and cloning. Most of them secreted IgM.lambda. antibodies. A sandwich enzyme-linked immunosorbent assay was developed with rabbit anti-V. vulnificus polyclonal antibodies as capture antibody, an IgM monoclonal antibody as detector antibody, and goat anti-mouse IgM-alkaline phosphatase conjugate as developer antibody. The range of detection was 10$\^$4/ to 10 V. vulnificus cells per microplate well. When four related Vibrio species were tested for cross-reactions, V. parahaemolyticus showed 3.5% reactively and V. carchariae, V. fluvialis, and V. furnisii showed negligibal (<1%) cross-reactivity.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.267-270
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• 2010

We designed a sensitive and specific PCR-based method with enterobacterial repetitive intergenic consensus (ERIC) primer to detect Erwinia pyrifoliae, which cause shoot blight in Asian pear, from a mixed culture and infected plant materials. The primers specifically detected only E. pyrifoliae and showed no cross-reactivity with other bacterial phytopathogens.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.698-699
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• 2005

Levels of fumonisins, mycotoxins produced by fungal species, must be accurately and rapidly monitored to ensure food safety. In this study, using surface plasmon resonance sensor, a batch-type biosensor was fabricated to detect fumonisin $B_1$. By applying this biosensor to fumonisin $B_1$ solutions of 0 to 6 ppm, a significant calibration model was developed for measurement. Coefficient of determination in regression analysis for the model was 0.920. Results indicate that detection of fumonisin $B_1$ by surface plasmon resonance biosensor was highly feasible.

• Research in Plant Disease
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• v.7 no.3
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• pp.123-133
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• 2001

Many pathovars of the species Pseudomonas syringae are known to produce different phytotoxins as secondary metabolites. Although phytotoxins generally enhance the virulence of P. syringae, they are not required for pathogenesis. Among the phytotoxins produced by P. syringae, lipodepsipeptides, coronatine, phaseolotoxin, and tabtoxin are the most well-known toxins which have been intensively studied for their structure, mode of action, biosynthesis, and regulation. A polymerase chain reaction (PCR) technique that amplifies a segment of the phytotoxin gene cluster using a primer set has been developed in recent years. This method offers the advantages of speed and sensitivity compared to the approaches based on physiological and biochemical methods. PCR detection of genes involved in the production of toxins could be exploited for early diagnosis of plant diseases caused by P. syringae pathovars.

• Korean Journal of Veterinary Service
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• v.23 no.3
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• pp.227-233
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• 2000

Salmonella enteritidis is the most prevalent etiologic agents of foodborne acute gastroenteritis. Direct isolation and identification of S enteritidis are time consuming work and not so highly sensitive. This study was conducted to develop for the specific detection of S enteritidis using polymerase chain reaction(PCR). PCR primers were selected to amplify a 351-base pair(bp) DNA fragment from the salmonella plasmid virulence A(spv A) gene of S enteritidis. With the primers, 351 bp DNA products were amplified from S enteritidis but not from other B, D, Cl serogroup Salmonella spp. It was sensitive to detect up to 40 pg of template DNA by agarose gel electrophoresis. This PCR assay is very rapid and specific method and less time consuming than the standard bacteriological methods.

• International Journal of Oral Biology
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• v.41 no.3
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• pp.149-154
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• 2016

The purpose of this study was to develop Streptococcus sobrinus-specific qPCR primers based on the nucleotide sequence of the RNA polymerase ${\beta}-subunit$ gene (rpoB). The specificity of the primers was determined by conventional polymerase chain reaction (PCR) with 12 strains of S. sobrinus and 50 strains (50 species) of non-S. sobrinus bacteria. The sensitivity of the primers was determined by quantitative real-time PCR (qPCR) with serial dilutions of the purified genomic DNAs (40 ng to 4 fg) of S. sobrinus ATCC $33478^T$. The specificity data showed that the S. sobrinus-specific qPCR primers (RTSsob-F4/RTSsob-R4) detected only the genomic DNAs of S. sobrinus strains with a detection limit of up to 4 fg of S. sobrinus genomic DNA. Our results suggest that the RTSsob-F4/RTSsob-R4 primers are useful in detecting S. sobrinus with high sensitivity and specificity for epidemiological studies of dental caries..

• KSBB Journal
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• v.17 no.1
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• pp.1-13
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• 2002

Label-free optical methods for the monitoring of interactions between biological molecules have become increasingly popular within the last decade. A rising number of publications have demonstrated the benefits of direct biomolecular interaction analysis(BIA) for biology and biochemistry, such as antigen-antibody Interactions, receptor-ligand interactions, protein-DNA, DNA- intercalator, and DNA-DNA interactions. This article gives an overview of the historical development, principle and application of label-free optical biosensor to examine the functional characteristics of biospecific interaction, such as kinetics, affinity, and binding position of biomolecular between an immobilized species at the transducer surface and its dissolved binding partner.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.611-614
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• 2003

The electrochemical oxidation of ascorbic acid(AA), serotonin(SE) and epinephrine(EP) have been performed at poly N,N-dimethylaniline(PDMA) film coated diamond electrode. This cationic polymer film is electrochemically deposited on boron-doped diamond electrode surface. Unlike the bard electrode, the polymer film-coated diamond electrode can well separate the oxidation potential of AA by 200mV. Thus this electrode can be successfully used for the simultaneoud detection of both species. Increases in the concentration of AA do not affect the reponse of EP and SE.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.90.1-90.1
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• 2013

Nature utilizes various of the colorization process. Some species of birds can express their mood of tempers by changing their collagen structures on skin. For example, turkey can change their skin color by expansion of the collagen structures, which are associated with the distinct color changes. Here, we developed bioinspired virus-based colorimetric sensors which can be genetically tuned for target molecule. Using M 13 bacteriophage, we fabricated responsive self-assembled color matrices composed of quasi-ordered fiber bundle structures. These virus matrices can exhibit color change by stimuli through fiber bundle structure modulation. Upon exposure of volatile organic compounds, the resulting multi-colored matrices exhibited distinct color changes with different ratios that can be recognized by the naked eyes. Using the directed evolutionary approaches, we genetically engineered the virus matrix to incorporate binding motif for explosive detection (i.e., trinitrotoluene (TNT)). Through utilizing a common handheld device (i.e., iPhone), we could distinguish TNT molecules down to 20 ppb in a selective manner. Our novel biomimetic virus colorimetric sensor can overcome current limitation for low response selectivity.