The study focuses on the development and validation of a dual-wavelength UV spectrophotometric method designed to estimate ketoconazole in topical formulations containing its cocrystal with 4-hydroxybenzoic acid. The aim was to eliminate potential interference from the coformer during analysis. Methods: Cocrystals were prepared using the solvent evaporation technique. A dual-wavelength method employing 241 nm and 249 nm was optimized to selectively quantify ketoconazole in the presence of its coformer. Validation was performed according to ICH guidelines, assessing parameters such as linearity, accuracy, precision, specificity, robustness, and ruggedness. The method’s practical applicability was tested in in vitro release studies using a Franz diffusion cell system and an optimized receptor medium. Results: The method demonstrated excellent linearity across a range of 20–140 µg/mL with a correlation coefficient 0.9909. Good recovery and results with a relative standard deviation of less than 2% were achieved, indicating high accuracy and precision. The selected wavelengths enabled successful discrimination of ketoconazole from coformer interference. Application to diffusion studies further confirmed the method’s suitability for evaluating drug release from the formulation. Conclusion: This validated UV spectrophotometric method offers a straightforward, reliable, and interference-free approach for estimating ketoconazole in cocrystal-based topical systems. It is especially suitable for in vitro release studies where conventional methods may face challenges due to spectral overlap.

Mayuri Namade; Akanksha Soman; Ashwini Wani*; Anita Ayre

Ketoconazole; Cocrystal; Dual-wavelength UV Method; Coformer