Study on the determination of amoxicillin and metronidazole by RP-HPLC

OBJECTIVE To develop a RP-HPLC method to determine the content of amoxicillin and metronidazole Simaltaneously in vitro.METHODS A reversed phase C18column(150×4.6mm 1.D.,5μm)was used for the determination amoxicillin and metronidazole with a mobile phase composed of 10mm phosphate buffer solution(pH4.0)-methanol(95∶5,v/v)at a flow rate of 1.0 ml·min-1.The detector was operated at the 254nm wavelength.RESULTS The chromatography was good and do not interfered by other components.The method recoveries were 99.10±1.3% for amoxicillin and 100.1±1.0% for metronidazole.The limits of detection were 0.02μg·mL-1and 0.05μg·mL-1.The intra-and inter-day imprecision(C.V.)did not exceed 1.7%CONCLUSION The method is accurate,sensitive and convenient,and is suitable for the determination of amoxicillin and metronidazole simultaneously.