AbstractThe aim of the study was to design and validate a reversed phase high performance liquid chromatography method for the separation and quantification of two active pharmaceutical ingredients (ciprofloxacin hydrochloride, hydrocortisone) and a preservative (benzyl alcohol) in ear drops. Effective separation of the examined compounds was achieved on a GraceSmart™ RP 18 column (150 mm × 4.6 mm, 5 μm) with gradient elution and a diode array detector. The total assay run time was 25 min. Analytical method validation assays were performed. Validation parameters used for the evaluation were: specificity, linearity, trueness, precision (repeatability and reproducibility), limit of detection and limit of quantitation. Results of the validation procedure (high recoveries, good standard deviations, no interfering peaks at the retention times corresponding to the analytes) confirm that the developed chromatographic method can be applied for routine analysis of ear drops.