Development and Validation of a Robust RP-HPLC Method for the Simultaneous Analysis of Exemestane and Thymoquinone and Its Application to Lipid-Based Nanoformulations

The present study describes the development and validation of a simple and rapid HPLC method for the simultaneous quantification of exemestane and thymoquinone. The separation of both compounds was performed on a 5 μ C-18 column utilizing phase A as water/methanol (45:5 v/v) and phase B as acetonitrile (50 v/v) (total ratio of A/B = 40:60 v/v) in isocratic elution mode as the mobile phase at a flow rate of 0.8 mL/min. Further, the Box–Behnken design was used for optimizing the analytical method. The proposed method was validated for various parameters, and all parameters were found to be within an acceptable range. The simultaneous detection of both drugs was monitored at 243 nm with a retention time of 5.73 and 6.93 min, respectively. Moreover, the forced degradation studies were conducted under various stress conditions, and the relevance of the validated RP-HPLC method was further explored for the estimation of drugs from lipid-based nanoformulation. Taken together, the study construed the development of an efficient and robust method that could be used for the quantification of these agents in various in vitro as well as in vivo models.