A RP-HPLC-UV method for the dual detection of fluconazole and clobetasol propionate and application to a model dual drug delivery hydrogel

Advanced drug delivery systems have become widely investigated to improve the efficacy of treatments for several diseases. These devices offer improved efficient, sustained, and targeted delivery which improves patient compliance, quality of life and minimises potential systemic side effects. As these therapeutic devices have advanced there is a potential for the development of products which deliver multiple drugs for simultaneous treatment of diseases. Given the interest in these dual-delivery devices it follows that new analytical methods need to be developed to detect and quantify different analytes during device development and validation. Here, for the first time, a reverse-phase high performance liquid chromatography (RP-HPLC) method is validated, utilising UV detection, for the dual detection of fluconazole and clobetasol propionate. The method is tested on a dual loaded model implant material intended as mucosal patches for the direct treatment of lichen planus and associated fungal infections. The method described here exhibited specificity and robustness with accurate and precise results. Good linearity was obtained between 0.25 and 2.5 mg mL−1 for fluconazole and 5 and 50 μg mL−1 for clobetasol propionate, with an R2 value of 0.9999 for the dual detection of fluconazole and clobetasol propionate. The developed method demonstrated selectivity and the solution containing both fluconazole and clobetasol propionate remained stable over a range of storage temperatures for up to 28 days. Within this validation study, the protocol was applied to a relevant dual loaded film showing the suitability of the method in studying drug release characteristics. The method described here also has a broader applicability for analysis and quantification of in vitro and in vivo drug release studies.