Abu-Shady H, Girgis E H
J Pharm Sci. 1978 May;67(5):618-21. doi: 10.1002/jps.2600670511.
Spectrophotometric assays are proposed for the determination of 3-dimethylaminomethylkhellin hydrochloride and khellin in bulk chemical and dosage forms. The acid dye method, using methyl orange at pH5, is applied to assay the amine in the form of an ion-pair extractable in chloroform with maximum abosrbance at 420 nm. The perchloric acid method, depending on formation and extraction of the oxonium salts of both compounds, is used to assay the amine and khellin at 333 or 430 nm and at 325 or 410 nm, respectively. The reineckate method can be used to assay the amine as the reineckate derivative in acetone with maximum absorbance at 530 nm. However, small amounts of the amine (1.5--3 mg) can be determined as the reineckate in methanol with maximum absorbance at 245 nm. Stability determination of the two compounds can be done by the acid dye and perchloric acid methods. The three methods are sufficiently accurate, sensitive, and precise.
本文提出了分光光度法用于测定原料药及制剂中盐酸3-二甲氨基甲基凯林和凯林的含量。采用在pH5条件下使用甲基橙的酸性染料法，以离子对形式测定胺，该离子对可在氯仿中萃取，在420nm处有最大吸收。高氯酸法基于两种化合物的氧鎓盐的形成和萃取，分别用于在333或430nm处测定胺，以及在325或410nm处测定凯林。雷氏盐法可用于测定丙酮中作为雷氏盐衍生物的胺，在530nm处有最大吸收。然而，少量的胺（1.5 - 3mg）可在甲醇中作为雷氏盐测定，在245nm处有最大吸收。两种化合物的稳定性测定可通过酸性染料法和高氯酸法进行。这三种方法足够准确、灵敏且精密。
