Determination of bromophos residues by fluorogenic labelling with dansyl chloride and thin-layer. Chromatography
1Laboratoire de Chimie Physique Organique et d'Analyse Instrumentale, Département de Chimie, Faculté des Sciences, Université de Dakar, Dakar-Fann Sénégal.
Abstract:
The use of a highly sensitive and inexpensive method for determination of residues of bromophos (an organophosphate pesticide) in peanut crops, by fluorogenic labelling and thin-layer chromatography (TLC) is described. The bromophos is hydrolysed and the product 4-bromo-2,5-dichlorophenol (BDCP) dansylated with dansyl chloride. The fluorescent dansylated BDCP is separated by TLC and detected fluorimetrically. Linear fluorimetric analytical curves are obtained for bromophos weights ranging between 0.5 and 50 ng. The minimum detectable quantity is estimated to be 0.5 ng. The method can be used to recover as little as 400 ng of bromophos residue from 25 g of peanut seeds.
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