Determination of 9-Deoxo-9a-Aza-9a-Homoerythromycin A and Related Substances by High-Performance Liq

A high-performance liquid chromatography(HPLC) method was developed and validated for the assay of 9-deoxo-9a-aza-9a-homoerythromycin A and related substances that might coexist in products as impurities that originate from the synthesis processes. A chromatographic system comprising an ODS 150 mm ×4.6 mm I.D. column, a mobile phase of cetonitrile monobasic potassium phosphate buffer (25/75), a flow rate of 1.2 mL/min, a temperature of 30 ℃ and a UV detector set at 205 nm has shown good chromatographic separation for 9-deoxo-9a-aza-9a-homoerythromycin A and other related substances. The linearity of the calibration curves, the precision, expressed as relative standard deviations, of the HPLC method have been studied. The HPLC method under study was found to be specific, precise, accurate and reproducible, indicating stability.