Simultaneous Estimation of Difluprednate and Moxifloxacin Hydrochloride In Ophthalmic Emulsion by UV- Visible Spectroscopy

Two simple, accurate, precise, reproducible, requiring no prior separation and economical procedures for simultaneous estimation of difluprednate and moxifloxacin hydrochloride in combined dosage form have been developed. First method employs formation and solving of simultaneous equation using 241nm and 288 nm as two analytical wavelengths for both drugs in distilled water. The second method is a Q value analysis based on measurement of absorptivity at 241nm and 264nm (as an ISO-absorptive point). Difluprednate at their respective λmax 241 nm and 288 nm and at iso-absorptive point 264 nm shows linearity in a concentration range of 10-20 μg/mL and similarly moxifloxacin at their respective λmax 288 nm and 241 nm and at iso-absorptive point 264 nm shows linearity in a concentration range of 1-5 μg/mL. The results of the analysis have been validated statistically.