催化光度法测定氧氟沙星氯化钠注射液中氯化钠的含量

Determination of sodium chloride in the ofloxacin and sodium chloride injection by catalytic spectrophotometry

目的:建立一种简便、灵敏的氧氟沙星氯化钠注射液中氯化钠含量的新的催化光度测定法。方法:在稀硫酸介质中,利用氯化钠对溴酸钾氧化甲基红褪色反应的催化作用,使甲基红在最大吸收波长519 nm 处的吸光度明显降低,且此吸光度的降低ΔA 与氯化钠的浓度具有定量关系,由此测定氯化钠的含量。结果:氯化钠的含量在0～22μg·mL^(-1)范围内与ΔA 呈线性关系,方法的检测限为1.23×10^(-6)μg·mL^(-1),加标回收率为96.4%～98.7%。结论:本法简便、快速、结果准确,适用于氧氟沙星氯化钠注射液的质量控制。

Objective：A new simple and sensitive catalytic spectrophotometry method for the determination of sodium chloride in the ofloxacin and sodium chloride injection was established. Method： The absorption of methyl red at the wavelength of 519nm decreased due to the decoloration of methyl red in a oxidation reaction with potassium bromate being catalyzed by sodium chloride in a medium of dilute sulfuric acid solution. The amount of sodium chloride could be determined based on the quantity relation between decrease of absorption and the amount of sodium chloride. Results： The decrease of absorption was linearly proportional to sodium chloride concentration in the range of 0 -22 μg·mL^-1. Detection limit of the method was 1.23 × 10-6 μg·mL^-1 and the recovery was 96.4% - 98. 7%. Conclusion：The method is simple, quick and precise and its assay result is suitable for the quality control of sodium chloride in the ofloxacin and sodium chloride injection.