Graham R E, Biehl E R, Kenner C T
J Pharm Sci. 1978 Mar;67(3):360-3. doi: 10.1002/jps.2600670323.
A rapid, quantitative analysis for betamethasone and its organic esters at room temperature is described. The method is similar to the official blue tetrazolium reaction for corticosteroids, except that methylene chloride is used as the solvent. The reaction is complete in 27-69 min, and the formazans produced are stable for at least 90 min after the addition of tetramethylammonium hydroxide. The results of the analysis of 13 different pharmaceutical formulations by the proposed method are reported. The degradation of betamethasone and its esters caused by strong bases is a pseudo-first-order reaction in methylene chloride. The average half-life of the corticosteroids studied is 56 min under the basic conditions described.
本文描述了一种在室温下对倍他米松及其有机酯进行快速定量分析的方法。该方法类似于皮质类固醇的法定蓝四氮唑反应，只是使用二氯甲烷作为溶剂。反应在27 - 69分钟内完成，加入氢氧化四甲铵后生成的甲臜至少稳定90分钟。报道了用该方法对13种不同药物制剂的分析结果。强碱引起的倍他米松及其酯的降解在二氯甲烷中是准一级反应。在所描述的碱性条件下，所研究的皮质类固醇的平均半衰期为56分钟。
