亚铁氰化钾作掩蔽剂的自动电位滴定法测定复方硫酸锌滴眼液中硼酸含量  

Determination of boric acid contentin compound zinc sulfate eye drops by potentiometric titration on potassium ferrocyanide as masking agent

作　　者：田文欣[1] 俞浩杰 TIAN Wen-xin;YU Hao-jie(Shanxi Radio ＆ TV University,Xi＇an 710119,China;Drilling and Production Engineering and Technology Research Institute of Chuan Qing Drilling and Exploration Corporation,Xi＇an 710018,China)

机构地区：[1]陕西广播电视大学,陕西西安710119 [2]川庆钻探工程公司工程技术研究院,陕西西安710018

出　　处：《化学工程师》2018年第7期42-44,17,共4页Chemical Engineer

摘　　要：针对复方硫酸锌滴眼液国家质量标准的硼酸检验方法缺陷,提出以亚铁氰化钾作掩蔽剂的自动电位滴定法测定其硼酸含量。向5 m L样品内添加4 m L 0.05mol·L^(-1)亚铁氰化钾溶液与15 m L甘油溶液后,搅拌反应2 min(50 r·min^(-1)),利用Na OH标准溶液自动电位滴定至等当点结束,通过等当点滴定液消耗体积,计算药物的H_3BO_3含量。该方法简便、快速、自动化程度高,可有效避免药物中共存的Zn SO_4干扰,同时解决终点指示困难,从而保证结果具有较好的精密度与准确度。Because of national quality standard of compound zinc sulfate eye drops had deficiency, the approach of potentiometrictitration with potassium ferrocyanide as masking agent was proposed to measure the boric acid content of the eye drops. The 4 mL potassium ferrocyanidesolution that concentrationwas0.05mol/Land glycerinumthat concentrationwas 0.05mol/Lwere added into the 5 mL sample solution.After stirring reaction time about 2 min（50 r·min-1）, potentiometric titrate to equivalent point, then boric acid content was obtained by consumption volume of titrant. The approach have characteristic of simple and quick, highly automation,effectively avoid interferenceof sulfate, solvethe problem that discoloration of end point is not sensitive, so that the measuring result possesspreferableprecisionand accuracy.

关 键 词：复方硫酸锌滴眼液 自动电位滴定 硼酸 亚铁氰化钾 掩蔽剂 

分 类 号：O655.2[理学—分析化学]