Abstract
A liquid chromatographic method for the determination of gentamycin in animal tissue is described. Gentamycin is quantitatively extracted from animal tissue with potassium phosphate buffer and the extract is deproteinated. The deproteinated extract is acidified to pH 6.4 – 6.5 with sulfuric acid and is purified by ion exchange gel chromatography (CM-sephadex). After elution from the ion exchange column with alkaline buffer, the eluent is further purified using a silica Sep-pak cartridge and derivatized on the cartridge with O-phthalaldehyde. The derivatized gentamycin is eluted from the Sep-pak cartridge with ethanol, and analyzed by liquid chromatography with fluorometric detection. Recoveries ranged from 86 to 108% in samples fortified with gentamycin at 0.5 to 10 ppm levels. The detection limit was 0.2 ppm.