电位滴定法标定高氯酸滴定液及其应用

Perchloric acid titrant-standardization by potentiometric titration and its application

目的:建立一种用电位滴定法标定高氯酸滴定液的分析方法,并将其结果运用于多种化学原料药的分析。方法:采用电位滴定对高氯酸滴定液(用DG113-SC电极)进行标定,再以相同方法测定盐酸多巴酚丁胺、硝酸硫胺和甘氨酸的含量。结果:用电位滴定法标定,线性关系好(r=0.9999),精确度更高,重复性更好,并且可以避免人为视觉误差。用电位滴定法标定与传统的酸碱指示剂法标定相比,两者之间存在一定差异。将其运用到化学原料药的分析,两种标定方法的结果对含量测定存在系统误差。结论:在药物分析过程中,对于使用电位滴定法测定药品含量的滴定液,应使用电位滴定法来标定其浓度,可以减小方法误差,使测量结果更严密。

Objective:To establish the analysis method of perchloric acid titrant-standardization by potentiometric titration.Methods:Perchloric acid solution(DG113-SC Electrode)was standardized by potentiometric titration.Contents of dobutamine hydrochloride,thiamine nitrate and glycine were determined by the same method.Results:Titrant-standardization by potentiometric titration has a good linear relation(r=0.999 9),higher accuracy,repeatability and avoids visual deviation as compared with traditional indicator standardization.Titrant-standardization has certain diversity between potentiometric titration and indicator titration.There is systematic error in two results obtained from different methods of standardization when applied to the analysis of active pharmaceutical ingredient(API).Conclusion:The titrant used to detect drug content in pharmaceutical analysis by potentiometric titration should be standardized by potentiometric titration in order to reduce method deviation and obtain more accurate conclusion.