Abstract:

A reversed-phase high performance liquid chromatographic method (RP-HPLC) with pre-column derivatization and ultraviolet (UV) detection was established to determine ethambutol hydrochloride in fixed dose combinations (FDCs) for anti-tuberculosis drugs. The derivatization was carried out in a non-aqueous environment, where ethambutol hydrochloride was derivatized with phenylethylisocyanate at an optimal molar ratio of 1∶6. The extraction recovery was 98.7% with the mean relative standard deviation of 0.70%. The accuracy and precision of the method were all qualified. The linear regression of the standard calibration curve was determined and the linearity was good (r=0.9993). The method is sensitive, specific, rapid, and can be successfully applied to the quantitation and dissolution of ethambutol hydrochloride in FDCs.

Key words: high performance liquid chromatography (HPLC), ethambutol hydrochloride, fixed dose combinations (FDCs) , pre-column derivatization