Priya Varshney

A simple, sensitive, precise, accurate and economic Q-absorption ratio method for the quantitative determination of betamethasone sodium phosphate and ofloxacin in bulk and combined dosage form has been developed and validated. Q absorption ratio method uses the ratio of absorbances at two selected wavelengths, one which is iso-absorptive point and other being the λ-max of one of the two components. Betamethasone sodium phosphate and ofloxacin shows an iso-absorptive point at 247nm in methanol, the second wavelength used was 289nm, which is λ-max of ofloxacin. The linearity was obtained in the concentration range of 2-12 ug/ml for both the drugs in distilled water. The proposed method is recommended for routine analysis. The results of analysis have been validated statistically and by recovery studies.

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.