Spectrophotometric Determination of Quetiapine Fumarate in Bulk and Dosage Form

A simple, rapid, economical and sensitive visible spectrophotometric method for the estimation of Quetiapine fumarate has been developed based on the formation of ion-pair of Quetiapine fumarate with dye bromocresol green in acidic medium, which was extracted into chloroform. It has absorption maxima at 415nm. Beer's law limit was found to be 5-25mcg/ml. The molar absorptivity was found to be 4.5x10⁴(mole⁻¹ cm ⁻¹) and sandell's sensitivity was 0.01949 (μg/cm²/0.001 absorbance unit). The correlation coefficient (r) was found to be 0.9999. The limit of detection (LOD) and limit of quantification (LOQ) was found to be 0.29 and 0.88 mcg/ml respectively of Quetiapine fumarate. The result of estimation in marketed formulations were found to be 97.44±0.3286 and 96.68±0.07854. The proposed method was applied successfully for the determination of Quetiapine fumarate in tablets with average recovery of 98.83±0.2738 and 98.98±0.3535. The method was then validated statistically as per ICH guidelines, which yielded good results concerning range, linearity, precision and accuracy.