电位滴定法测定氨茶碱片中乙二胺的含量

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。

Content Determination of Ethylendiamine in Aminophylline Tablets by Potentiometric Titration

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.