紫外光谱法测定阿司匹林及水杨酸双组分体系含量的方法学比较

Methodological comparison of determining the contents of two-component system of aspirin and salicylic acid by ultraviolet spectrometry

目的 :对双组分体系含量测定中运用的多种计算分光光度法的优劣进行比较。 方法 :以阿司匹林和水杨酸双组分体系为例 ,对等吸收双波长及系数倍率法、差量线性法、水解法、导数曲线下面积法等的部分效能指标与结果进行比较。 结果 :经典的等吸收双波长及系数倍率法的适用范围比较广 ,但对条件要求比较严格 ;差量线性法和导数曲线下面积法的适用范围较窄 ,但是操作简便、结果准确 ,在某些条件下是首选方法 ;水解法只是理论上的一种创新探索 ,尚不适宜于实际操作。结论 :上述方法各有优劣 ,可根据分析体系的光谱特性 ,选择适宜的分析方法。

Objective: To compare the merits and demerits of several UV spectrophotometric methods in determining the contents of two-component system. Methods: A two-component mixture of aspirin and salicylic acid (SA) was employed as the example. The linear range, recovery and other performance parameters of several computational methods including isosbestic-dual-wavelength method, K-ratio method, differential linearity method, hydrolysis method, and area-under-derivative-curve method were compared. Results: The classical isosbestic-dual- wavelength method and K-ratio method could be applied to a wide range of samples under relatively strict control of operational conditions. On the contrary, the applicable ranges of differential linearity method and area-under-derivative-curve method were relatively narrow,but they might be the first-choice under some conditions since they were simple and accurate. The so-called hydrolysis method was an explorative way for the analysis of the specific mixture, and needed further verification. Conclusion: Suitable computational methods can be chosen according to the spectrometric characteristics of the analytic system.