Department of Analytical and Food Chemistry, Faculty of Pharmacy, Damascus University, Damascus, Syria
This article describes the development of a new, selective and extraction-free spectrophotometric method for the determination of gliclazide (GLZ) in both pure form and pharmaceutical formulation preparations. The proposed method is based on nucleophilic substitution reaction of GLZ with 1, 2-naphthoquinone-4-sulfonic acid sodium salt (NQS) in methanol solvent to form reddish orange product peaking at 454 nm. The stoichiometry of the reaction was studied by Job's method of continuous variation. The parameters that affect the reaction were carefully optimized. Under the optimized reaction conditions, Beer's law was obeyed in the concentration range of 30–110 μg/ml with correlation coefficient (R2=0.9978). Intra-day and inter-day precision and accuracy of the method were established by following the International Conference of Harmonization (ICH) guidelines, the limit of detection(LOD) and quantification(LOQ) were also reported. The method is successfully applied to the estimation of GLZ in its pharmaceutical tablets without interference from excipients and additives.
Gliclazide, 1, 2-naphthoquinone-4-sulfonic acid sodium salt (NQS), Nucleophilic Substitution, Spectrophotometric Method, Pharmaceutical Formulation
