Development and Validation of Spectrophotometric and Stability Indicating RP-HPLC Method for the Simultaneous Estimation of Gatifloxacin and Flubiprofen Sodium in Ophthalmic Dosage Form

The main objective of this work is to develop simple, precise, accurate and reproducible UV-Spectrophotometric and Stability indicating RP-HPLC methods for simultaneous estimation of Gatifloxacin (GAT) and Flubiprofen sodium (FLU) in ophthalmic dosage form.

Dual wavelength spectrophotometric method which involves solving of simultaneous equations based on the measurement of absorbances at 289 nm and 248 nm, which are the absorption maxima (λmax) of GAT and FLU respectively. The RP-HPLC analysis is carried out on Shiseido C18 column (250 mm × 4.6 mm I.D.), using 1% orthophosphoric acid in water and acetonitrile in the ratio of (40: 60% v/v) as the mobile phase with a flow rate of 0.9 ml/min. The detection was carried out at a wavelength of 236 nm.

The retention times were found to be 2.152±0.2 min and 7.881±0.2 min for GAT and FLU respectively. The linearity range was found to be 10–20 μg/ml and 1–2 μg/ml for Gatifloxacin and Flubiprofen sodium respectively by UV method and 10–30 μg/ml and 1–3 μg/ml for Gatifloxacin and Flubiprofen sodium respectively by HPLC method. The percentage recoveries of both the drugs GAT and FLU from the ophthalmic form were 99.51% and 99.58% respectively by UV method and 99.08% and 99.43% respectively by HPLC method. The correlation coefficients of both the drugs were found to be more than 0.99 by two methods. Other parameters like ruggedness, robustness etc. was well within the acceptance criteria.

Both UV-spectrophotometric and stability indicating RP-HPLC methods were found to be accurate, rapid, precise and simple. These simple methods can be used for the simultaneous estimation of GAT and FLU in bulk and in ophthalmic dosage forms.