电位滴定法测定氨茶碱片中乙二胺的含量

Content Determination of Ethylendiamine in Aminophylline Tablets by Potentiometric Titration

目的:改进氨茶碱片中乙二胺含量测定的方法。方法:采用电位滴定法进行测定。采用E-201-C型pH复合电极,用苯二甲酸盐标准缓冲溶液和混合磷酸盐缓冲液对pH计进行校正。采用0.1mol·L-1氢氧化钠溶液滴定,用二阶微商法计算滴定终点。结果:精密度试验乙二胺含量为13.88%,RSD=0.28%(n=3);乙二胺的平均回收率为99.37%,RSD=0.18%(n=6)。结论:该方法准确、精密度好,不受片剂辅料干扰。

To improve the determination method of ethylenedeiamine in amimophylline tablets. METHODS： Potentiometic titration method was used to determine the contents of ethylenediamine. E-201-C type pH composite electrode was adopt ed using phthalate buffer solution and mixed phosphate buffer solution to correct pH meter. 0.1 mol·L^-1 sodium hydroxide solution was used for titration and end-point titration was calculated by second-order derivative. RESULTS： The content of ethylenedeiamine was 13.88% （RSD=-0.28%, n=-3） with an average recovery of 99.37% （RSD=0.18%, n=6）. CONCLUSION： The method is accurate and precise, and it is not interfered by the excipients of aminophylline tablets.