• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1043-1047
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• 2008

Simultaneous determination of amitraz, bromopropylate, coumaphos, cymiazole and 2,4-dimethylaniline in 200 honey samples purchased in Korea was performed by reversed-phase high-performance liquid chromatography with multiple UV detection. 2% Acetone in hexane was used for a liquid-liquid extraction and 20-40% water in acetonitrile solutions were used as mobile phases. The LOD for the analytes varied between 0.4 and 1.5 $\mu$g/L and the recoveries were yielded between 64 and 94%. Relative standard deviation of the repeatability of the method is less than 15%. Amitraz was not present in amount above 10 $\mu$ g/L and one for coumaphos and cymiazole and two for bromopropylate, and three for 2,4-dimethylanilne were detected in amount above 10 $\mu$ g/ L. Levels of the acaricide residues found were less than 50 $\mu$ g/L.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1131-1136
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• 2013

Parabens, the esters of p-hydroxybenzoic acid, have been widely used as antimicrobial preservatives in cosmetic products, drugs, and processed foods and beverages. However, some parabens have been shown to have weak estrogenic effects through in vivo and in vitro studies. Because such widespread use has raised concerns about the potential human health risks associated with exposure to parabens, we developed a simultaneous analytical method to quantify 4 parabens (methyl, ethyl, propyl, and butyl) in human urine, by using solid-phase extraction and high-performance liquid chromatography coupled with triple quadrupole mass spectrometry. This method showed good specificity, linearity ($R^2$ > 0.999), accuracy (92.2-112.4%), precision (0.9-9.6%, CV), and recovery (95.7-102.0%). The LOQs for the 4 parabens were 1.0, 0.5, 0.2, and 0.5 ng/mL, respectively. This method could be used for quick and accurate analysis of a large number of human samples in epidemiological studies to assess the prevalence of human exposure to parabens.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.219.2-219.2
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• 2003

We want to actively cope with technological developments by improving our drug specification in Korean Pharmaceutical Codex. Pheniramine maleate and naphazoline HCl of Pheniramine Maleate and Naphazoline Hydrochloride Ophthalmic Solution were ordained as UV spectroscopy and HPLC, respectively. Simultaneous analysis of those using HPLC has been developed. The assays of two drug products were 97.2%, 102.2% (pheniramine maleate), 96.8%, 101.3% (naphazoline HC1) respectively ; the specification rage if 90.0∼110.0%. (omitted)

• Research in Plant Disease
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• v.23 no.4
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• pp.363-366
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• 2017

Barley mild mosaic virus (BaMMV), Barley yellow mosaic virus (BaYMV) and Barley yellow dwarf virus (BYDV) have been identified as an important causative agents for an economically important disease of winter barley in Korea. In this study, a multiplex reverse transcription polymerase chain reaction (mRT-PCR) method was used for the simultaneous detection. Three sets of virus-specific primers targeted to the capsid protein coding genes of BaMMV, BaYMV and BYDV were used to amplify fragments that were 594 bp, 461 bp, and 290 bp, respectively. Several sets of primers for each target virus were evaluated for their sensitivity and specificity by multiplex RT-PCR. The optimum primer concentrations and RT-PCR conditions were determined for the multiplex RT-PCR. The mRT-PCR assay was found to be a better and rapid virus diagnostic tool of specific barley diseases and potential for investigating the epidemiology of these viral diseases.

• Journal of Environmental Science International
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• v.18 no.12
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• pp.1369-1381
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• 2009

The simultaneous determination of residual pesticides was developed using a gas chromatography. In this study, a simple and reliable methodology was improved to detect 175 kinds of residual pesticides by a liquid-liquid extraction procedure, followed by chromatographic analysis by gas chromatography. The 175 kinds of residual pesticides was classified into 4 groups according to the chemical structure, column type, resolution and sensitivity. The soybean sample selected for recovery experiment was not detected any pesticides. The recovery rates were ranged from 70.6% to 119.7% in most pesticides. The relative standard deviation (RSD 0.3~5.6%) was lower than 5.6% in all cases. The limits of detection (LOD) was lower than the maximum residue levels established by Korean legislations. The method has been successfully applied to the analysis of approximately 130 real samples.

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.133-147
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• 2009

In order to develop the simultaneous analytical method for pesticide residues which ones in soil are rapidly and inexpensively measured by, many analytical methods for individual pesticide residue and several methods for multi-pesticide residues in agricultural commodities and food were reviewed. Various gas chromatographic conditions and pre-treatment procedures were intensively investigated and modified. And then new optimum procedure was established and its proficiency was validated. The response on detectors of simultaneous determination of 180 pesticides out of pesticides used in Korea was tested. The number of pesticides that their limits of detection (LOD) equal or lower than $0.05\;mg\;kg^{-1}$ were 137 pesticides on ECD, 170 pesticides on NPD and 179 pesticides on ECD/NPD integrated. The retention times of most pesticides ranged appropriately between 10 minutes and 40 minutes in the proposed chromatographic conditions. But about 90 pesticides eluded between 20 minutes and 30 minutes and so they were not resolved enough. In partition with dichloromethane, ethyl acetate/hexane (1:1) and ethyl acetate, number of pesticides whose extraction efficiency ranged from 70% to 120%, were 163, 154 and 147, respectively.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.181.2-181
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• 2005

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1244-1250
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• 2000

A method for simultaneous quantitative determination of plasticizers such as diethyl phthalate(DEP), di-n-propyl phthalate(DprP), di-n-butyl phthalate(DBP), di-n-pentyl phthalate(DPP), butylbenzyl phthalate(BBP), di-(2-ethylhexyl) phthalate(DEHP), dicyclohexyl phthalate(DCHP) and di-(2-ethylhexyl) adipate(DEHA), which are suspected as endocrine disruptors, in food was studied. A analysis method was optimized for the quantification of plasticizers in Jjambbong, which is a kind of fatty noodle, by using GC/FID. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 3.5, 5.3, 2.2, 2.2, 7.2, 1.7, 1.9 and 3.0 mg/kg, respectively. Much higher recovery was obtained by extraction with acetone/n-hexane(1:1) rather than hexane solvent system. The recovery of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 72.7, 85.9, 91.4, 97.1, 100.8, 103.2, 104.3 and 95.8% after 4 time extractions, respectively. The migration of plasticizers from PVC wraps into PVC wrap covered Jjambbong was conducted after shaking(120 rpm) for 30min at room temperature with chosen solvent system. It was found that the migration level of DEHA were 577, 706, 770 mg/kg into Jjambbong, respectively, while the other plasticizers were not observed.

• The Plant Pathology Journal
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• v.17 no.2
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• pp.106-109
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• 2001

A multi-rapid immunofilter paper assay (multi-RIPA) system was prepared for simultaneous diagnosis of three Tobamoviruses, Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), and Zucchini green mottle mosaic virus (ZGMMV) in cucurbitaceous crops. Each of these viruses was specifically detected by the multi-RIPA from cucumber, watermelon, zucchini, and bottle gourd inoculated with the three Tobamoviruses singly or in combination. The three viruses could infect cucumber, watermelon, and bottle gourd ; however, CGMMV could not infect zucchini as the latex-coated CGMMV antibody showed a negative reaction in the multi-RIPA of the virus-infected plant extract. When the minimum detection level of multi-RIPA was compared with that of double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) using CGMMV, the latter was 10 times more sensitive than the former. The detection limit of the multi-RIPA for the purified CGMMV was 50 ng/ml. In a survey of the threeviruses in cucurbits growing in commercial fields in 1999 and 2000, CGMMV was detected in watermelon and cucumber, and ZGMMV was detected only in zucchini growing in plastic houses at the suburbs of Chonju, Korea. However, KGMMV was not found in the commercially growing cucurbit crops in our study, The results suggest that the multi-RIPA can be a simple, rapid, specific and convenient tool to detect simultaneously the Tobamoviruses.