Jpc-journal of planar chromatography-modern tlc vol:14 issue:5 pages:347-349
A quantitative thin layer chromatographic (TLC) method on silica gel, with ethyl acetate-acetone-alcohol, 62 + 40 + 3 (v/v) as mobile phase, has been developed for the determination of olaquindox at ppm levels in animal feed. Preliminary purification consists of extraction with water, adsorption on XAD-4, washing, and elution with acetonitrile. Before the ellution step acetylolaquindox is added as internal standard. The residue obtained after evaporation of acetonitrile is dissolved in a small volume of methanol. Quantitation is performed by densitometry at lambda = 360 nm.