Determination of the Potencies of Oxytetracycline Crude Drug and Its Tablets by Turbidimetric Method / 中国药房

ABSTRACT

OBJECTIVE:To establish a turbidimetric method for the determination of the potency of the crude drugs and tablets of oxytetracycline. METHODS: By turbidimetric method in which Staphylococcus aureus was used as the test organism with biomass concentration of 1.0%～1.5% (V/V). The culture temperature was 37 ℃ and the culture time was about 4 h. The method was compared with the cup-plate method in potency. RESULTS: The linear range of oxytetracycline was 0.05～0.4 IU?mL-1. The average recovery of the crude drug of oxytetracycline was 99.59% (RSD=2.0%) and that of oxytetracycline tablets was 99.51% (RSD=1.91%), showing no significant difference as compared with the cup-plate method in contents. CONCLUSIONS: The method was sensitive and rapid yet with few influencing factors thus applicable for the determination of the potencies of oxytetracycline and its tablets.