In Vitro New Dissolution Method for the Evaluation of Roxithromycin using pH 6.0 Phosphate Buffer and Determination of its Content by Validated UV Spectrophotometric Method

A rapid dissolution method was developed for the evaluation of Roxithromycin tablets and the determination of Roxithromycin content was done by UV-spectrophotometer. The proposed method comprises the measurement absorbance of standard concentrations of Roxithromycin in the pH 6.0 phosphate buffer solution against wavelength maximum [max] of 205 nm. Beer's Law limits were obeyed in the concentration range of 1μg/ml - 10μg/ml. The linear regression coefficient was estimated to be 0.999 and the linear regression equation obtained was y=0.0954x-0.0014. The solutions were stable for more than 12 hours. The method has been extended for the determination of Roxithromycin content in tablets after the dissolution for 60 minutes at 50 rpm using USP Apparatus II [Paddle apparatus] under experimental conditions. The unknown concentration of Roxithromycin in the solution was estimated from the standard curve and it was found to be within the range of the labeled claim. The relative standard deviation of six replicate solutions was determined to be 0.55. No interference of excipient and coating material was found in this method. This method is economical, precise and accurate. Hence, this method can be employed for the routine evaluation of Roxithromycin tablets by dissolution and dissolution profile by using pH 6.0 phosphate buffer as a medium.