Analysis of tobramycin by liquid chromatography with pulsed electrochemical detection

The determination of tobramycin by liquid chromatography using a column pac ked with poly(styrene-divinylbenzene) and pulsed electrochemical detection on a gold electrode is described. The mobile phase consisted of an aqueous solution containing 52 g/l of sodium sulfate, 1.5 g/l of sodium octanesulfo nate and 50 ml/l of a 0.2 M phosphate buffer pH 3.0. The total time of anal ysis was not more than 30 min. The effects of the different chromatographic parameters on the separation were also investigated. When a number of comm ercial samples of tobramycin was analyzed using this method, nine different components were separated, five of which are of unknown identity. (C) 2000 Elsevier Science B.V. All rights reserved.