Reverse phase Liquid chromatographic method for the estimation of clozapine from tablet dosage forms

A simple and specific reverse phase high performance liquid chromatographic method was developed and validated for the estimation of clozapine in tablet dosage forms. A Lachrom C 18 column having 250 x 4 i.d in an isocratic mode with mobile phase containing acetonitrile: phosphate buffer (70:30% v/v) was used. The flow rate was 1.0 ml/min and the retention time of clozapine was found to be 3.06 min. The method was validated for specificity, linearity, accuracy, limit of quantification and limit of detection. The limit of quantification and limit of detection for the estimation of clozapine were found to be 0.1 μg and 0.5 μg respectively. Experimentally developed fast dissolving tablets of clozapine showed recovery levels in the range of 98.88-100.32 %, while assay of marketed samples showed a recovery of 97.85 to 101.45 % of their label claim. It was concluded that the proposed method could be an easy and economic method for the quantitative determination of clozapine in tablet dosage forms.