SPECTROPHOTOMETRIGAL DETERMINATION OF LAMOTRIGINE DRUG IN ITS BRANDED TABLETS

摘要

Three highly sensitive spectro photometric methods for the determination of Lamotrigine in pharmaceutical tablets and other preparation have been procured. These methods are selective. Methods 02 and 03 are extremely sensitive and are applicable in ngmL~(-1) levels too. Its method is based on the formation of chloroform extractable ion-pair complex between lamotrigine and Bromophenol blue reagent at a lower pH 1.45. with a maximum absorption wavelength at 424 nm. In methods (02) and methods (03) the lamotrigine-Bromophenol blue ion pair is dissolved in either ethanolic sulphuric acid and resulting acid form of the dye is measured at 424 nm or in ethanolic KOH and resulting base form of the dye is measured at 600 nm. All variables that can affect the drug-dye complexation and its extraction into chloroform have been investigated and its optimum values have been achieved. Beer's law was obeyed in all these three methods. The limits of detection (LOD) and LOQ (Limits of quantification) have also been calculated. The accuracy and precision of the methods have been evaluated on intra day and inter day basis and the relative error (RE) and the relative standard deviation (RSD) have been also observed. The proposed methods can be successfully applied for the determination of lamotrigine in bulk powder or in tablets too equally.