A HIGHLY SENSITIVE GAS-CHROMATOGRAPHIC DETERMINATION OF LEVAMISOLE INMILK

Art efficient extraction and sensitive gas chromatographic method is d escribed for the determination of the anthelminthic drug levamisole in milk. Levamisole was extracted from alkaline milk with ethyl acetate. Clean-up of the extract was by a series of liquid-liquid extraction s teps. Levamisole residues in the extract were determined by gas chroma tography with a nitrogen-phosphorus detector. This method was satisfac tory for determining levamisole residues in milk as low as 0.5 ng/g. M ean recoveries of 0.5-10.0 ng/g fortified milk samples ranged from 84. 5 to 95.2%. Five replicate analyses performed on a milk containing inc urred levamisole residues yielded a mean of 3.34 ng/g levamisole with a CV of 3.0%.