A new RP-HPLC method development and validation for simultaneous estimation of lamotrigine and zonisamide in pharmaceutical tablet dosage formulations

Abstract

A simple, specific, rapid, accurate and sensitive RP-HPLC method was developed and validated for the simultaneous estimation of Lamotrigine and Zonisamide in bulk drug and pharmaceutical tablet dosage form. The separation was achieved by using C₁₈ column (250mm×4.6mm, 5μm particle size), Inertsil ODS using a mobile phase of mixed phosphate buffer (pH 3) adjusted with ortho phosphoric acid : acetonitrile (50:50 v/v), with a flow rate of 1.0 ml/min at an ambient temperature of 30˚C and at 232 nm as detection wave length. Rt values (Rt = retention time) of Lamotrigine and Zonisamide were found to be 2.666 min and 3.958 min respectively. Lamotrigine and Zonisamide follow Linearity in the concentration range of 5-30μg/ml with a correlation coefficient of 0.9998 and 0.9997 for Lamotrigine and Zonisamide respectively. Percentage purity of Lamotrigine and Zonisamide were found to be 99.45% and 99.66 %w/v respectively. The proposed method has been validated for specificity, linearity, range, accuracy, precision and robustness were within the acceptance limit according to ICH Q2(B) guidelines and the developed method can be employed for determination Lamotrigine and Zonisamide in the bulk and combined pharmaceutical dosage form(tablets).