• Korean Journal of Environmental Agriculture
• /
• v.39 no.3
• /
• pp.246-252
• /
• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.

• Proceedings of the PSK Conference
• /
• 2000.10a
• /
• pp.250.2-251
• /
• 2000

• Proceedings of the PSK Conference
• /
• 2000.04a
• /
• pp.197.2-197.2
• /
• 2000

• Preventive Nutrition and Food Science
• /
• v.12 no.2
• /
• pp.126-130
• /
• 2007

Noroviruses, members of the family Caliciviridae, are often found in shellfish grown in polluted water and are emerging as a leading cause of foodborne disease worldwide. As the presence of norovirus in food commodities becomes an important medical and social issue, there are increasing needs for designing improved detection methods for the virus. In this study, we tested the Agilent 2100 Bioanalyzer for the analysis of norovirus DNA amplified from oyster samples. Microchip electrophoresis provided us with more accurate information, compared to conventional agarose gel electrophoresis, in the resolution and quantification of amplified products. The development of an improved method for food-associated noroviruses would contribute to a rapid identification of contaminated food and improve our understanding of the modes of food contamination and norovirus transmission.

• Food Science and Industry
• /
• v.40 no.1
• /
• pp.22-26
• /
• 2007

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
• /
• 2004.05a
• /
• pp.245-245
• /
• 2004

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.280.1-280.1
• /
• 2003

The high-performance liquid chromatography method was performed for test method development of related compounds in pharmaceuticals. Using reverse-phase column and gradient elution of 1 ％ acetonitrile-acetonitrile: H20:triethylamine (70:30:0.5), lansoprazole, 2-hydroxybenzimidazole, 2-mercaptobenzimidazole, lansoprazole sulfone, lansoprazole sulfide could be individually identified and quantitated. (omitted)

• YAKHAK HOEJI
• /
• v.55 no.4
• /
• pp.345-351
• /
• 2011

Gastritis is the most common disease among Korean. The demand for the development of gastritis drugs has been increasing. Currently, however, there is no guideline available for the clinical evaluation of gastritis drugs worldwide. As a consequence, domestic and international pharmaceutical companies make errors in the drug development processes, and it becomes difficult for them to establish the scientific validity and objectivity of newly developed drugs. The objective of this study was to develop the Guideline for Clinical Trials Evaluation of Gastritis which can be used in improving the quality and consistency of clinical trials. First, we collected and reviewed the clinical trials on gastritis drugs that were available from Japan Pharmaceuticals and Medical Devices Agency and Korea Food and Drug Administration (KFDA), and investigated the recent research trends on clinical trials of gastritis drugs. Reviewers from KFDA and National Institute of Food and Drug Safety Evaluation and scientific experts from the pharmaceutical industries developed the guidelines through regularly scheduled meetings. Opinions and consultation from academic fields and industry experts were also obtained. This project will provide the clinical trial practitioners, investigator and reviewers the scientific and rational guidelines for performance and evaluation of clinical trials for gastritis drugs. Furthermore, we hope this guideline contributes to establishing the national competitiveness, improving the quality of clinical trial, and encouraging researches on drug development for gastritis.

• Korean Journal of Environmental Agriculture
• /
• v.32 no.3
• /
• pp.207-213
• /
• 2013

BACKGROUND: This study was conducted to develop analytical method with reproducibility, accuracy and applicability to agricultural products than the existing methods. METHODS AND RESULTS: Mean recoveries of thidiazuron ranged from 89.2 to 91.2 in hulled rices, 87.2 to 92.1 in peppers, from 76.4 to 86.9 in potatoes, from 91.2 to 95.7 in watermelons, from 86.5 to 88.5 in kiwi fruits, and from 89.5 to 94.0 in grapes, with less than 10% of relative standard deviations. In addition, the limit of quantitation was set to be 0.05 mg/kg and there were no interfering peaks in integrating the thidiazuron peak. CONCLUSION(S): These results represent that the enhanced analytical method has reliable accuracy, precision, selectivity, and sensitivity.

• Proceedings of the PSK Conference
• /
• 2002.04a
• /
• pp.111.1-111.1
• /
• 2002