交流示波极谱滴定在药物分析中的应用——Ⅰ.四苯硼钠滴定甲基硫酸新斯的明注射液

交流示波极谱滴定可有效地应用于四苯硼钠滴定甲基硫酸新斯的明。先加入四苯硼钠,使之与新斯的明产生沉淀,然后以硫酸亚铊标准溶液滴定多余的四苯硼钠。以dE/dt—E曲线上四苯硼钠切口的消失为终点。用此法测定了注射液中新斯的明含量,回收率为99.3～100.2%,十次测定的相对标准偏差为0.42%。远较药典方法方便、快速。

APPLICATIONS OF A C OSCILLOPOLAROGRAPHIC TITRATION IN PHARMACEUTICAL ANALYSIS——Ⅰ. TITRATION OF NEOSTIGMINE METHYL SULFATE INJECTION WITH SODIUM TETRAPHENYLBORATE

In this paper, it is shown that a c oscillopolarographic titration can be applied advantageously to titrate neostigmine methyl sulfate by sodium tetraphenylborate(NaTPB).NaTPB is added to precipitate quantitatively, neostigmine methyl sulfate from aqueous solution. Filter part of the mixture, and the excess of NaTPB in the filtrate is titrated by thallous sulfate standard solution, using the disappearance of the incision of NaTPB on dE/dt—E curve to indicate the end point of titrations. The recovery was 99.3～100.2%. Ten determinations on the same samplegave a relative standard deviation of ±0.42%. The method is accurate, rapid and Simple, much superior to the official method adopted now.