• Food Science and Biotechnology
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• v.17 no.3
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• pp.547-552
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• 2008

The detection of carbamate (carbofuran, carbaryl, benfracarb, thiodicarb, and methomil) and organophosphate (diazinon, cadusafos, ethoprofos, parathion-methyl, and chlorpyrifos) pesticide residues with very low detection limits was carried out using surface plasmon resonance (SPR) based equipment. The capacity to develop a portable SPR biosensor for food safety was also investigated. The applied ligand for the immunoassays was polyclonal goat anti-rabbit immunoglobulin (IgG) peroxidase conjugate. Concentration tests using direct binding assays showed the possibility of quantitative analysis. For ligand fishing to find a proper antibody to respond to each pesticide, acetylcholinesterase (AChE), and glutathione-S-transferase (GST) were tested. The reproducibility and precision of SPR measurements were evaluated. With this approach, the limit of detection for pesticide residues was 1 ng/mL and analysis took less than 11 min. Thus, it was demonstrated that detecting multi-class pesticide residues using SPR and IgG antibodies provides enough sensitivity and speed for use in portable SPR biosensors.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.223-228
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• 1998

Turnip mosaic virus)TuMV-Ca) was isolated from a Chinese cabbage showing severe mosaic and black necrotic spots symptoms in Korea. The virus was identified as a strain of TuMV by its host range test, particle morphology, serology, double stranded RNA analysis. For detection of the virus, reverse transcription and polymerase chain reaction(RT-PCR) was performed with a set of 18-mer TuMV-specific primers to amplify a 876 bp DNA fragment The virus was rapidly detected from total nucleic acids of virus infected tissues as well as native viral RNA of purified virion particles by RT-PCR. Detection limit of the viral RNA by RT-PCR was 10 fg.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3959-3962
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• 2011

A simple propargylamide-fuctionalized chemodosimeter was prepared for the ratiometric fluorescence detection of mercuric ions in HEPES buffer. The chemodosimeter exhibited $Hg^{2+}$-induced propargyl amide-tooxazole transformation, with a significant accompanying ratiometric change in fluorescence. It afforded high selectivity for mercuric ion detection without any competitive inhibition by common alkali, alkaline earth, or other transition metal ions. The probe showed a $17{\times}10^{-6}M$ detection limit for $Hg^{2+}$ ions and potential applicability for detecting aqueous $Hg^{2+}$ ions.

• Korean Journal of Veterinary Research
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• v.54 no.2
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• pp.113-115
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• 2014

Salmonella are causative agents of gastroenteritis and systemic disease in animals. The invA gene was selected as a target sequence of loop-mediated isothermal amplification (LAMP) assay for diagnosis of Salmonella infection. The detection limits for broth dilution, spiked feces and enrichment were $10^4$, $10^5$ and $10^2$ CFUs/mL, respectively. The LAMP assay developed in the present study may be a reliable method for detection of Salmonella spp. in pig feces.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.42-48
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• 1999

Engine misfire causes of the negative effect on exhaust emission such as HC, CO, and NOX . Moreover, it causes damage to the three-way-catalyst(TWC) system permanently. The crankshaft velocity fluctuation(CVF) method has been applied for the real cars as misfire detection system usually, which utilizes the crank angle sensor input to calculate the variation of the crankshaft rotational speed. But this approach has the limit due to the fact that three could be problem under certain engine condition like as deceleration or high speed condition . Therefore the development of new methods are requested today. This study introduced the new method of misfire detection using breakdown voltage(BDV) characteristics between spark plug electrouds.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1334-1336
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• 2001

In this study, laser ablation atomic fluorescence (LAAF) spectroscopy has been applied for a nanometer-scale surface analysis of Na-doped polymethyl methacrylate (PMMA). LAAF spectroscopy is a new sensitive element detection technique which involves atomizing of a sample by the laser ablation and detection of ablated plume by laser-induced fluorescence (LIF) spectroscopy. Using this technique in the detection of Na atoms with Na-doped PMMA, a detection limit is obtained as 36 fg for single laser shot. Further, the depth distribution in the sample is measured with a very high spatial resolution using a two-layer PMMA sample by observing the shot-by-shot LIF intensity from the Na atoms.

• Journal of Food Hygiene and Safety
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• v.3 no.2
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• pp.65-73
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• 1988

T-2 toxin is one of mycotoxins produced by fungi such as Fusarium spp. and possesses a potent cytotoxicity to eukaryotic cell. The contamination of mycotoxins in cereals and feedstuffs is one of the great concerns in health authorities. Therefore, the development of the specific, sensitive and simplified analysis method for T -2 toxin is required. During more than ten years, several chemical and biological analysis methods were proposed and applied for the detection and quantification of T-2 toxin. TLC, GLC-FID and GC-MS are widely employed, but these methods required numerous clean-up procedures before analysis, and the detection limit for T-2 toxin is more than 10 ppb. Biological analysis methods with dermal tissues and cultured cells are not specific to T-2 toxin, since T-2 toxin and other related derivatives possess a similar toxicological activity although their relative activity is different each otber. Based on tbe specific reaction between antibody and antigen, the authors tried to introduce the immunochemical methods for determination of T-2 toxin. The enzyme-linked immunosorbent assay method using monoclonal antibody for T-2 toxin was applied to analyse T-2 toxin. The detection limit of T-2 toxin by ELISA method was 0.1 ppb. The correlation between ELISA and GC-MS method on these samples was very high. ELISA method developed for the detection and quantification of T -2 toxin in this paper possesses simplicity, high sensitivity and specific for T-2 toxin. Furthermore, the ELISA method with T-2 toxin monoclonal antibody was an excellent tool for the screening of Fusarium spp. which was suspected to produce T-2 toxin.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.11a
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• pp.23-29
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• 2003

Detection in remotely sensed images can be conducted spatially, spectrally or both [2]. If the images have high spatial resolution, materials can be detected by using spatial and spectral information, unless we can't see the object embedded in a pixel. In this paper, we intend to solve the limit of spatial resolution by using the hyperspectral image which has high spectral resolution. Therefore, the Linear Spectral Mixing(LSM) Model which is sub-pixel detection algorithm is used to solve this problem. To find class Endmembers, we applied Geometric Model with MNF(Minimum Noise Fraction) transformation. From the result of sub-pixel detection algorithm, we can see the detection of water is satisfied and the object shape cannot be extracted but the possibility of material existence can be identified.

• Journal of Sensor Science and Technology
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• v.16 no.6
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• pp.449-456
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• 2007

The work described in this study concerns the development of a disposable amperometric sensor for the electrochemical detection of a well-known aqueous pollutant, free available chlorine (FAC). The FAC sensor developed used screen printed carbon electrodes (SPCEs) coupled with immobilised syringaldazine, commonly used as an indicator in photometric FAC detection, which was directly immobilised on the surface of SPCEs using a photopolymer PVA-SbQ. To enable in-field analysis of FAC, a prototype hand-held electrochemical analyzer has been developed to withstand the environment with its rugged design and environmentally sealed connections; it operates from two PP3 (9 volt) batteries and is comparable in accuracy and sensitivity to commercial bench top systems. The sensitivity of the FAC sensor developed was $3.5{\;}nA{\mu}M^{-1}cm^{-2}$ and the detection limit for FAC was found to be $2.0{\;}{\mu}M$.

• Journal of Sensor Science and Technology
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• v.19 no.6
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• pp.421-427
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• 2010

Alizarin Red S modified screen printed carbon electrodes were developed for the electrochemical detection of aluminum ion. The electrodes developed use screen-printed carbon electrodes(SPCEs) coupled with chemical modification with an organic chelator, Alizarin Red S(ARS), for aluminum ion detection in aqueous solution. For sensor fabrication ARS was directly immobilized on the surface of SPCEs using PVA-SbQ(The poly(vinyl alcohol) bearing stryrylpyridinium groups). Aluminum concentrations were indirectly estimated by amperometric determination of the non-complexed ARS immobilized on the electrodes, after its complexation with aluminum. The sensitivity of the sensor developed was $3.8\;nA{\mu}M^{-1}cm^{-2}$ and the detection limit for aluminum was $25\;{\mu}M$.