Characterisation of dirithromycin and spiramycin using high performance liquid chromatography and direct infusion mass spectrometry

Two different high performance liquid chromatography procedures and two detection modes (spectrophotometric and electrochemical) and direct infusion mass spectrometry were used for the characterisation of two macrolide antibiotics, spiramycin and dirithromycin, showing multisignal response in liquid chromatography. In the spiramycin standard three forms were determined qualitatively and quantitatively. The degradation metabolite of dirithromycin, erythromycylamine, was also identified.