Sensitive and Simple Spectrophotometric Method for the Determination of Lamotrigine in Pure and Pharmaceutical Preparations of Charge-transfer Complex

Abstract

A simple, rapid and sensitive spectrophotometric method has been proposed for the determination of lamotrigine in pharmaceutical preparations. The charge-transfer (CT) interactions between lamotrigine as electron donor and 7,7,8,8-tetracyanoquinodimethane (TCNQ), as pi-electron acceptors have been investigated spectrophotometrically. The obtained complex was measured spectrophotometrically at 843 nm. The optimum experimental conditions have been studied carefully. Beer's law is obeyed over the concentration range of 2.0-25 mu g/mL. The detection and quantification limits were 0.95 and 2.85 mu g/mL, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery and robustness. Good values of precision are obtained, intra-day mean RSD are 0.82-0.98 % and the inter- day RSD are 0.79-0.87 %. The method is applicable for the assay of the investigated drug in tablet form and the results are in good agreement with those obtained by the reference HPLC method. The proposed procedures were successfully applied to the determination of lamotrigine in tablet form, with high percentage of recovery, good accuracy and precision.