• Journal of The Korean Astronomical Society
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• v.22 no.1
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• pp.25-30
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• 1989

We report a null detection of $^{12}CO$ emission from a sub-condensation in a High Velocity Cloud (HVC). As a consequence of this, an upper limit of $n(H_2)\frac{X(CO)}{DV/DR}{\leq}2{\times}10^{-5}$ was set. This implies that $^{12}CO$ abundance is deficient by at least a factor of 10 if the HVC is predominantly molecular, otherwise the CO abundance of the HVC might be normal.

• Journal of Sensor Science and Technology
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• v.21 no.4
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• pp.311-317
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• 2012

Disposable amperometric screen-printed biosensor strips have been fabricated by a sol-gel encapsulation for the analysis of glucose. The glucose oxidase(GOx) is entrapped in the gel matrix through sol-gel transition of tetraethoxysliane(TEOS). The biosensor is fabricated by GOx containing thin film of TEOS gel on the surface of screen-printed carbon electrode(SPCE). The GOx-containing thin film of TEOS gel offers a one-step modification process on the surface of SPCE. The optimum conditions for glucose determination have been characterized with respect to the applied potential, enzyme loading ratio, and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 16.0 mM and 0.25 mM, respectively.

• Journal of the Optical Society of Korea
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• v.14 no.2
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• pp.65-76
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• 2010

Plasmonic-based biosensing technologies have been successfully commercialized and applied for monitoring various biomolecular interactions occurring at a sensor surface. In particular, the recent advances in nanofabrication methods and nanoparticle syntheses provide a new route to overcome the limitations of a conventional surface plasmon resonance biosensor, such as detection limit, sensitivity, selectivity, and throughput. In this paper, optical and physical properties of plasmonic nanostructures and their contributions to a realization of enhanced optical detection platforms are reviewed. Following vast surveys of the exploitation of metallic nanostructures supporting localized field enhancement, we will propose an outlook for future directions associated with a development of new types of plasmonic sensing substrates

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.595-601
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• 2017

In vivo assay of glucose detection was described using a skin tattoo film electrode (STF), and the probe was made from carbon nano tube paste modification film paper. Here in the square-wave stripping anodic working range obtained of $20-100mgL^{-1}$ within an accumulation time of 0 seconds only in sea water electrolyte solutions of pH 7.0. The relative standard deviations of 50 mg glucose that were observed of 0.14 % (n=12), respectively, using optimum stripping accumulation of 30 sec, the low detection limit (S/N) was pegged at 15.8 mg/L. The developed results can be applied to the detect of in vivo skin sensing in real time. Which confirms the results are usable for in vitro or vivo diagnostic clinical analysis.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3696-3700
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• 2012

The colorimetric and fluorescent cyanide recognition properties of 2-[(9-ethyl-9H-carbazol-3-yl)methylene]-propanedinitrile (1) in $CH_3CN-H_2O$ (2/1, v/v, HEPES 10 mM, pH = 7.0) solution were evaluated. The optical recognition process of probe 1 exhibited high sensitivity and selectivity to cyanide ion with the detection limit of $2.04{\times}10^{-6}$ M and barely interfered by other coexisting anions. The sensing mechanism of probe 1 is speculated to undergo a nucleophilic addition of cyanide to dicyanovinyl group present in compound 1. The colorimetric and fluorescent dual-modal response to cyanide makes probe 1 has a potential utility in cyanide detection.

• Journal of Microbiology
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• v.40 no.2
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• pp.146-150
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• 2002

A multiplex polymerase chain reaction (PCR) assay was developed for the identification of two Candida species-albicans and dubliniensis. Three sets of primers were selected from different genomic sequences to specifically amplify a 516 bp fragment within the tops gene, specific for several species of the genus Candida (CCL primers); a 239 bp fragment within the $\alpha$INT1 gene, specific for Candida albicans (CAL primers); and a 175 bp fragment within the ALSD1 gene, specific for Candida dubliniensis (CDL primers). Using the primers in conjunction (multiplex PCR), we were able to detect both C. albicans and C. dubliniensis and to differentiate between them. The detection limit of the PCR assay was approximately 10 cells per milliliter of saline. Thus, this multiplex PCR assay can be applied for differentiation of C. albicans and C. dubliniensis from clinical specimens.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.177-184
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• 2019

An electrochemical detection method for capsaicin has been developed using ionic liquid (IL) doped graphene-titania-Nafion composite-modified electrode. The combination of IL (1-hexyl-3-methylimidazolium with hexafluorophosphate counter ion) in the composite-modified electrode resulted in a significantly increased electrochemical response for capsaicin compared to that obtained at the corresponding electrode without IL. The increased electrochemical signal could be ascribed to the decreased electron transfer resistance through the composite film and also to the effective accumulation of capsaicin on the electrode surface due to ${\pi}-{\pi}$ interaction of the imidazole groups of IL with the aromatic rings of capsaicin. The present IL composite-modified electrode can detect capsaicin with a concentration range from $3.0{\times}10^{-8}M$ to $1.0{\times}10^{-5}M$ with a detection limit of $3.17{\times}10^{-9}M$ (S/N = 3). The present sensor showed good reproducibility (RSD = 3.2%).

• Archives of Pharmacal Research
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• v.11 no.1
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• pp.56-60
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• 1988

A thin layer flow cell with cell volume of $8\;{\mu}{\ell}$ was constructed. Diffusion currents of ascorbic acid was directly proportional to the 1/3 power of volume flow rates. A linear dynamic range was obtained at the concentration range between $10^{-7}\;M\;and\;10^{-4}\;M$ of ascorbic acid with a detection limit of $10^{-8}\;M$. Ascorbic acid in the multivitamin product was amperometrically determined at TLFC after simply dissolving mg range ground product in $100m{\ell}$ of pH 7.0 phosphate buffer.

• Journal of Biosystems Engineering
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• v.31 no.6 s.119
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• pp.535-540
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• 2006

For a biosensor development, an enzyme-linked immunosorbent assay (ELISA) of the fungicide iprovalicarb was developed by minimizing the processing time. The time for whole incubation process was reduced from 135 minutes to 15 minutes. The concentration of antibody was varied to improve sensitivity. The total processing time was reduced from 2.5 hours to 20 minutes, the final sensitivity ($IC_{50}$ value) of 7.93 ng/mL and the lowest detection limit of 0.045 ng/mL were obtained. This ELISA was applied to potatoes and onions, and the recoveries were in the range of 98.85 $\sim$ 101.20% and 87.97 $\sim$ 102.70%, respectively. Accordingly, this method can be used as basis for a biosensor for rapid monitoring of iprovalicarb residues in crops.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.57-59
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• 2006

The purpose of search problem is to maximize the probability of target detection as limited search capability. Especially, as elapsing of time at a point of time of initial information received the target detection rate for searching an expected location due to a moving target such that wrecked ship or submarine decrease in these problems. The algorithm of search problem to a moving target having similar property of above targets should solve the search route as quickly as possible. In existing studies, they have a limit of applying in practice due to increasing computation time required by problem size (i.e., number of search area, search time). In this study, we provide that it takes more reasonable computation time than preceding studies even though extending a problem size practically using an approximate computation of probability.