A Simple UV Spectrophotometric Method for the Determination of Levofloxacin in Dosage Formulations

Purpose: The present study was undertaken to develop a validated, rapid, simple and low-cost ultraviolet (UV) spectrophotometric method for estimating levofloxacin (LFX) in dosage preparations. Method: UV spectrophotometric analysis was performed spectrophotometrically at a pre-determined λmax of 290 nm with 0.1M HCl as diluent/blank. The method was validated for linearity, accuracy, precision, reproducibility, and specificity as per International Conference on Harmonization (ICH) guidelines. The method was also used in the determination of the content of levofloxacin in two commercial brands of levofloxacin in the Nigerian market. Results: The regression data for the calibration plots exhibited good linear relationship (r = 0.999) over a concentration range of 0.25 - 12.0 µg/ml and the linear regression equation was y = 0.075x + 0.018. Mean recovery accuracy was 98.7 %, which was not significantly different from the expected value (p = 0.05), while coefficient of variation (CV) for both intra-day and inter-day was 7 %. The method was specific for levofloxacin in the presence of common excipients, and when it was applied to two marketed brands, levofloxacin content was 99.69 ± 2.38 and 102.65 ± 3.64 %, respectively, of labeled claim. Conclusion: The proposed method gave good validation results and the statistical analysis performed proved that the method is precise, accurate and reproducible, and hence can be employed for routine analysis of LFX in bulk and commercial formulations.