The gas-chromatographic determination of 2-chloro-4-nitrobenzamide, 3,5-dinitrobenzamide and 3,5-dinitro-o-toluamide in animal feeding stuffs

Abstract

A method is described for the determination of 2-chloro-4-nitrobenzamide (aklomide), 3,5-dinitrobenzamide (DNBA) and 3,5-dinitro-o-toluamide (zoalene) in animal feeding stuffs. These additives are extracted from the feed with methanol and the extract is treated with methanol-hydrogen chloride solution to form the methyl esters of the corresponding substituted benzoic acids. These are determined by gas chromatography with an electron-capture detector. DNBA and zoalene have similar retention times in the prescribed procedure, so that some method by which they can be distinguished is desirable. A modification of the method for this purpose is proposed.