Coumaphos detection limits

Organophosphorus pesticides, e.g. coumaphos, menazon, maretin, dursban 200 °C, 45 min Induced fluorescence or amplification of natural fluorescence, detection limits 1-80 ng. [21]... 

After drying in a stream of cold air coumaphos (hRj 30-35) appeared as an intense red chromatogram zone on a colorless background, while parathion methyl (hRj 40-45), fenitrothion (h/ f 45-50) and parathion ethyl (hRf 60-65) yielded yellow zones as they did with sodium hydroxide alone (. v.). The detection limit for coumaphos was 10 ng per chromatogram zone. 

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