Development and validation of a stability indicating HPLC method for the analysis of lornoxicam in powder for injection.

A rapid, isocratic stability indicating high performance liquid chromatographic method was developed and validated for the estimation of lornoxicam in its powder for injection. The analysis was performed on a Shimadzu VP-ODS (4. 6 mm x 15 cm, 5 µm) column. The mobile phase consisted of sodium acetate (pH 5.8; 0.05 M) and methanol (45:55) flowed at 1.0 ml/min. Detection was carried out at 290 nm. The developed method had the good ability to separate lornoxicam well from the degradation products. The regression data showed good linear relationship at the concentration range of 4.04-20.20 μ/mL with r(2)=0.9999. Specificity, linearity, accuracy, precision and robustness of the method were evaluated to validate the proposed method. Stressed degradation studies were conducted to provide an indication of its stability indicating property. The limits of detection and quantitation were 9.70 and 33.94 ng /ml, respectively. Lornoxicam was found to be stable in the mobile phase in 24 h. The co-existed excipients had no interference with the analytical procedure. Additional peaks appeared in the chromatograms of five kinds of forced degraded samples (light, heat, acid, base and oxidation degradation). Mean recovery assessed at three levels was from 99. 7 to 100.3%, indicating the good accuracy of the method. Repeatability and inter-day RSD of the method was determined to be 0.38% and 0.81%, respectively. The HPLC method was demonstrated to be robust for intentional minor changes of ratio, pH change, salt concentration and column temperature. The method should be utilized as the routine analysis and quality control of lornoxicam in injectable formulation.