胶体果胶铋胶囊含量测定方法的建立与比较

Establishment and comparison of content determination methods for colloidal bismuth pectin capsules

目的:建立准确度高,适用性强的胶体果胶铋胶囊的含量测定方法。方法:紫外-可见分光光度法以10%抗坏血酸溶液-20%碘化钾溶液^(-1)mol·L^(-1)硝酸溶液(2∶5∶1)为显色剂,测定波长463 nm;电位滴定法以光度电极为指示电极,测定波长590 nm,以二甲酚橙为指示剂,用0.05 mol·L^(-1)乙二胺四醋酸二钠滴定液进行滴定;原子吸收分光光度法以223.1 nm为测定波长。结果:紫外-可见分光光度法、电位滴定法与原子吸收分光光度法分别在2~20μg·mL^(-1)、30~70 mg、5~30μg·mL^(-1)范围内线性良好,平均回收率分别为100.0%(RSD=0.40%)、100.4%(RSD=0.49%)和100.3%(RSD=0.51%)。18批次样品按上述3种方法测定,含量范围分别为97.1%~104.8%、97.4%~105.0%和97.5%~104.8%。建立的3种方法均能准确测定胶体果胶铋胶囊含量,测定结果之间无统计学差异。结论:考虑仪器的普适性及方法的灵敏度,紫外-可见分光光度法更适用于胶体果胶铋胶囊的含量测定。

Objective:To establish a method with high accuracy and applicability for the content determination of colloidal bismuth pectin capsules.Methods:UV-Vis spectrophotometry used 10%ascorbic acid solution-20%potassium iodide solution-1 mol·L^(-1)nitric acid solution(2∶5∶1)as chromogenic agent,and the determination wavelength was 463 nm.Potentiometric titration was carried out using photometric electrode as indicator electrode at 590 nm,with xylenol orange as an indicator and 0.05 mol·L^(-1)EDTA as titration.The wavelength was measured at 223.1 nm by atomic absorption spectrophotometry(AAS).Results:The good linear relationships were found in the range of 2-20μg·mL^(-1),30-70 mg and 5-30μg·mL^(-1)for UV-Vis spectrophotometry,potentiometric titration and AAS,respectively.The average recoveries were 100.0%(RSD=0.40%),100.4%(RSD=0.49%)and 100.3%(RSD=0.51%).Eighteen batches of samples were determined by the above three methods,the content ranges were 97.1%-104.8%,97.4%-105.0%and 97.5%-104.8%,respectively.The three established methods could accurately determine the content of colloidal pectin bismuth capsules,and the results showed no significant difference.Conclusion:Considering the universality of the instrument and the sensitivity of method,UV-Vis spectrophotometry is more suitable for the content determination of colloidal bismuth pectin capsules.