Abstract

A simple, sensitive, and selective high-performance liquid chromatography (HPLC) method was developed and validated for the simultaneous quantification of fluorometholone (FLU) and tetrahydrozoline hydrochloride (THZ) in combined ophthalmic formulations. The effects of several factors, including detection wavelength, buffer pH, buffer concentration, and organic solvent concentration, on the performance of the method were investigated. The performance of the developed method was validated in accordance with the requirements of the International Conference on Harmonization. The linearity of the calibration curves in the desired concentration range was high for both FLU and THZ (r2 = 0.9999). The accuracy and precision of the method were determined by a recovery study at analyte concentrations of 80 %, 100 %, and 120 %. The recovery was 99.60–100.17 % for both analytes, with a relative standard deviation less than 1.0 % at any concentration level. The validated results indicate that the new HPLC method could be successfully applied for the simultaneous determination of FLU and THZ in ophthalmic suspensions.