A RAPID HPLC METHOD FAR THE QUANTIFICATION OF TYROTHRICIN, MENTHOL, AND BENZOCAINE IN PHARMACEUTICAL FORMULATIONS

A rapid, sensitive, and accurate reversed-phase HPLC method has been d eveloped for the analysis and quantification of pharmaceutical formula tions containing tyrothricin (1), an antibiotic used in antiseptic buc cal compressed tablets for local application. The assay has been carri ed out under isocratic conditions, using a stationary phase of alumina particles coated with polybutadiene and an alkaline mobile phase (pH = 8.2). No HPLC method was reported for the analysis of 1. So, this ne w technique is an alternative to the slow and tedious microbiological methods. On the other hand, it allows the simultaneous quantification of 1, benzocaine (2), and menthol (3), an aromatic compound not curren tly analyzed by liquid chromatography.