LIQUID-CHROMATOGRAPHY OF TYLOSIN-A AND RELATED SUBSTANCES ON POLY(STYRENE-DIVINYLBENZENE)

A liquid chromatographic method for analysis of tylosin A and related substances was developed using wide-pore poly(styrene-divinylbenzene) as the stationary phase. As a mobile phase, a mixture of tetrahydrofur an-0.2 M potassium phosphate buffer pH 9.0-water (20:5:75) was used at a flow-rate of 1.0 ml/min. The column was kept at 60 degrees C. Detec tion was performed by UV at 280 nm. Tylosin A is separated from all it s known related substances that are potentially present as impurities in commercial samples of tylosin base and tylosin tartrate. The method shows good linearity and repeatability and is stability indicating. R esults for a number of commercial samples analysed using the newly dev eloped method are presented.