Development of Simultaneous Derivative Spectrophotometric and HPLC Methods for Determination of 17-Beta-Estradiol and Drospirenone in Combined Dosage Form

Simple, rapid spectrophotometric, and reverse-phase high performance liquid chromatographic methods were developed for the concurrent analysis of 17-beta-estradiol (ESR) and drospirenone (DRS). The spectrophotometric method was based on the determination of first derivative spectra and determined ESR and DRS using the zero-crossing technique at 208 and 282 nm, respectively, in methanol. The linear range was 0.5–32.0  µ g·mL −1 for DRS and 0.5–8.0  µ g·mL −1 for EST. The limit of detection (LOD) values were 0.14  µ g·mL −1 and 0.10  µ g·mL −1 and limit of quantification (LOQ) values were 0.42  µ g·mL −1 and 0.29  µ g·mL −1 for ESR and DRS, respectively. The chromatographic method was based on the separation of both analytes on a C 18 column with a mobile phase containing acetonitrile and water (70 : 30, v/v). Detection was performed with a UV-photodiode array detector at 279 nm. The linear range was 0.08–2.5  µ g·mL −1 for DRS and 0.23–7.5  µ g·mL −1 for EST. LOD values were 0.05  µ g·mL −1 and 0.02  µ g·mL −1 and LOQ values were 0.15  µ g·mL −1 and 0.05  µ g·mL −1 for ESR and DRS, respectively. These recommended methods have been applied for the simultaneous determination of ESR and DRS in their tablets.