庆增安注射液中甲氧苄氨嘧啶的萃取－差示双波长分光光度测定

DETERMINATION OF TRIMETHOPRIM IN QINGZENG'AN INJECTION BY EXTRACTION DIFFERENTIAL DUAL-WAVELENGTH SPECTROPHOTOMETRY

本法采用氯仿萃取，再用差示双波长分光光度法测定庆增安中ＴＭＰ的含量。选定测定波长２９３．０ｎｍ，干扰物等吸收波长２７５．０ｎｍ。ＴＭＰ浓度在０～２４０μｇ／ｍｌ范围内符合Ｂｅｅｒ定律，△Ａ＝０．０１９０９Ｃ＋０．００５，ｒ＝０．９９９９，回收率１００％，ＲＳＤ＝０．４０％。方法简便，结果准确。

Trimethoprim in QINGZENG'AN injection was determined by differential dual-wavelength spectrophotometry between PH7 and 12 after extration with CHCl3.The measuring and referential wavelengths were 293 and 275 nm,and Beer's law was obeyed over the range of 0￣24μg/ml with analytical recovery 100.0%,cv 0.40%.This method was simple,convenient and reproducible.