双波长倍率系数法和一阶导数光谱法测定复方苯甲酸酊的含量

Determination of compound benzoic acid tincture by dual-wavelength ratio coef-ficient spectrometry and first derivative spectrometry

目的:建立复方苯甲酸酊中苯甲酸和水杨酸的含量测定方法。方法:采用倍率系数法于(272±1)nm和(301±1)nm波长处直接测定苯甲酸含量;采用一阶导数光谱法于(318±1)nm波长处直接测定水杨酸的含量。结果:苯甲酸:在19.34～27.08μg/mL浓度范围内,线性关系良好,相关系数r=0.999 9,平均回收率99.4％,RSD为0.80％。水杨酸:在24.48～34.27μg/mL浓度范围内,线性关系良好,相关系数r=0.999 9,平均回收率99.6％,RSD为0.490A。结论:本方法简便、快速、准确。

Objective:To establish a quantitative analysis method for benzoic acid and salicylic acid in compound benzoic acid tincture. Methods: The benzoic acid was determined directly at 272 and 301 nm by dual - wavelength ratio coefficient spectrometry. The salicylic acid was determined directly at 318nm by first derivative spectrometry. Results:The calibration curve of benzoic acid was linear in the range from 19. 34 to 27.08μg/mL with r =0.999 9,the average recovery and relative standard deviation were 99.4% and 0. 80% respectively. The calibration curve of salicylic acid was linear in the range from 24.48 to 34.27μg/mL with r =0.999 9, the average recovery and RSD were 99.6% and 0.49% respectively. Conclusion:The method is simple,rapid and accurate.