衍生化-离子液体萃取分光光度法测定盐酸美西律

盐酸美西律与1,2-萘醌-4-磺酸钠在pH=9.0的介质中反应生成一种橙红色衍生物,该衍生物能被离子液体所萃取,其最大吸收波长发生较大幅度红移,吸光度显著增强。据此建立了高选择性的测定盐酸美西律的衍生化-离子液体萃取分光光度法。萃取后的衍生物在448 nm处的表观摩尔吸光系数ε为2.69×104L·mol-1·cm-1。盐酸美西律浓度在0.2～5.4μg·mL-1范围内符合比耳定律,相关系数为0.9994,检出限为0.067μg·mL-1。该方法已用于药物制剂及尿样中盐酸美西律的测定,其回收率分别为99.5%～100.7%和96.6%～101.5%。

Determination of Mexiletine Hydrochloride by Derivative-Ionic Liquid Extraction Spectrophotometry

The derivatization reaction between mexiletine hydrochloride(MXT) and 1,2-naphthoquinone-4-sulfonate was studied by spectrophotometry.Mexiletine hydrochloride was found to react with 1,2-naphthoquinone-4-sulfonate to form an orange-red derivative and the absorbance of the derivative was greatly enhanced.The apparent molar absorptivity of the derivative at 448 nm was 2.69×104 L·mol-1·cm-1.Based on this,a simple,rapid,highly sensitive and selective spectrophotometric method was developed for the determination of mexiletine hydrochloride in aqueous solution.Under the optimum reaction conditions,there was a good relationship between the concentration of mexiletine hydrochloride and absorption in the range of 0.2~5.4 μg·mL-1,with r of 0.9994.The detection limit was 0.067 μg·mL-1.The proposed method has been applied to the determination of mexiletine hydrochloride in tablets and urine specimen.The recoveries ranged from 99.5% to 100.7% and 96.6%~101.5%,respectively.