电位滴定法测定消食化滞液中总有机酸的含量

Determination of the total organic acids content in Xiaoshihuazhi Ye by automatic potentiometric titration

目的建立自动电位滴定法测定消食化滞液中总有机酸含量,研究自动电位滴定法代替指示剂法进行消食化滞液中总有机酸含量质量控制的可行性。方法对新建立质控方法进行方法学验证,结果与指示剂法结果进行统计学比对。结果自动电位滴定法精密度、重复性、稳定性良好,平均加标回收率为101.2%,相对标准偏差为0.84%,三批消食化滞液中总有机酸含量为7.893~8.981 mg/mL。本法与指示剂法测定结果的精密度及含量均值均无显著性差异。结论自动电位滴定法可替代指示剂法进行消食化滞液中总有机酸含量的质量控制。

Objective To study on foundation of a new analytical method for the determination of the total organic acids content in Xiaoshihuazhi Ye by using automatic potentiometric titration(APT)and study on the feasibility by using APT instead of indicator method for the total organic acids content quality control.Methods The APT was adopted to detect the total organic acids content in Xiaoshihuazhi Ye.The proposed method was verified.The results by APT and results by the indicator method were compared.Results The titration jump was obvious at the end point and the proposed method owned high precision,repeatability and stability.The average adding standard recovery was 101.2%with high RSD(0.84%).The total organic acids content ranged from 7.893 to 8.981 mg/mL in three batches samples.The statistical comparison showed there was no significant difference between the precision and the average results of the two methods.Conclusion It is feasible to use the APT instead of the indicator method for the quality control of total organic acids content in Xiaoshihuazhi Ye.