钼蓝比色法测定伊班膦酸钠注射液中的游离磷酸盐

Determination of free phosphate in Ibandronate sodium injection by Molybdenum blue colorimetric method

目的用比色法测定伊班膦酸钠注射液中的游离磷酸盐。方法采用乙酸丁酯萃取注射液中的磷钼酸铵,再加入氯化亚锡-抗坏血酸溶液作为还原剂,生成稳定的蓝色化合物,测定波长为720 nm。结果方法的线性范围为1.0～10.0μg·mL-1,回收率为96.5%,RSD=1.17%(n=9)。结论所用方法简便、快速准确、重复性好,可用于测定伊班膦酸钠注射液中的游离磷酸盐。

OBJECTIVE To establish a clorimetric method for the determination of free phosphate in Ibandronate sodium injection. METHODS Butyl acetate extraction was used in aqueous solution of ammonium molybdate, and then stannous chloride - ascorbic acid solution was added as reducing agent, and a stable blue chemical compound was gained. The detected wavelength was 720 nm. RESULTS The calibration curve of free phosphate was linear beteen 1.0 - 10.0 μg· mL^- 1 , and the average recovery were 96.5 % , RSD = 1.17% （n = 9）. CONCLUSION The method is simple, rapid, accurate and reproducible,and can be used for the determination of free phosphate in this product.