Application of TLC for Confirmation and Screening of Pesticide Residues in Fruits, Vegetables, and Cereal Grains: Part 2. Repeatability and Reproducibility of Rf and MDQ Values
Autor: | I. Korsos, T. Hatfaludi, I. Füzesi, J. Lantos, M. Szathmary, Arpad Ambrus |
---|---|
Rok vydání: | 2005 |
Předmět: |
Reproducibility
Chromatography Pesticide residue Silica gel Elution Pesticide Residues Analytical chemistry Ethyl acetate Reproducibility of Results Food Contamination General Medicine Repeatability Pesticide Sensitivity and Specificity Pollution Thin-layer chromatography chemistry.chemical_compound chemistry Consumer Product Safety Fruit Vegetables Chromatography Thin Layer Edible Grain Food Science |
Zdroj: | Journal of Environmental Science and Health, Part B. 40:485-511 |
ISSN: | 1532-4109 0360-1234 |
Popis: | This paper illustrates the effect of major factors influencing the reproducibility of thin layer chromatography (TLC) separation and detection under largely differing environmental and laboratory conditions. The optimum conditions for reproducibility and detection sensitivity was obtained on 20 x 20 cm layer in the retention factor (Rf) range of 0.2-0.7 by applying the sample in spots of 3-4 mm diameter at 2 cm from the edge of the plate. The reproducibility rapidly decreased below Rf = 0.2. Above Rf = 0.2 the within-laboratory reproducibility of 219 pesticides obtained in ethyl acetate silica gel elution system by several laboratories was typically below 10%. The among-laboratories reproducibility of the average retention factors was generally below 12%. The minimum detectable quantities (MDQ) of 219 pesticide residues were determined with nine detection methods. The MDQ values largely varied depending on the mode of detection. Bioassay methods enabled the detection down to 0.1-10 ng, while 20-100 ng could be achieved with the chemical reagents. Higher MDQ values are also reported in order to assist the identification of compounds potentially present. The between-laboratories reproducibility of MDQ values was typically 1-5 MDQmin. |
Databáze: | OpenAIRE |
Externí odkaz: | |
Nepřihlášeným uživatelům se plný text nezobrazuje | K zobrazení výsledku je třeba se přihlásit. |