STABILITY INDICATING RP-HPLC METHOD DEVELOPMENT AND VALIDATION FOR ESTIMATION OF DALFAMPRIDINE IN ITS BULK AND FORMULATION.

A stability indicating reverse phase high performance liquid chromatographic method has been developed and validated for estimation of Dalfampridine in its bulk and formulation. Method development was carried out on Inertsil-C18 column, (250×4.6mm, particle size 5µ, maintained at ambient temperature). The chromatographic separation was achieved using a mobile phase containing acetonitrile and potassium dihydrogen phosphate buffer (pH was adjusted to 4 with orthophosphoric acid) in the ratio of 70:30 v/v at flow rate of 1.0 ml/min using detection at 298 nm. In the linear study, linearity was observed from 20-80 µg/ml with correlation coefficient of 0.999. The LOD and LOQ for the method were found to be 0.71µg/ml and 2.16µg/ml respectively. The statistical analysis shows that the method was found to be accurate, reliable, simple and reproducible. The values of relative standard deviation for precision did not exceed 2%. The chromatographic retention time of proposed method was 2.433 min. The percentage purity of Dalfampridine was found to be within the limit. For stability study, the drug was exposed to the stress conditions such as acid, alkaline, oxidation, thermal by using 0.1 M HCl, 0.1 M NaOH, 30% H2O2, 100º C. Degradation behaviour shows that the major degradation was observed at acidic condition (80.11%), followed by thermal (70.25%), alkaline (67.12%) and oxidation (63.42%). The proposed method was successfully applied for the quantitative determination of Dalfampridine in bulk and formulation.