الملخص

Abstract A direct simple, rapid and sensitive spectrophotometric method has been developed for the determination of domperidone maleate (DOM), carvedilol (CAR), dimetindene maleate (DIM), and cinnarizine (CIN) in bluk and pharmaceutical formulations. The method was based on the formation of ion association complexes between the studied drugs and erythrosine B dye in citrate buffer solution (pH4.5), which show maximum absorbance at 555 nm for DOM or in acetate buffer solution (pH5-5.3) and measure the absorbance at 556, 556, 555 nm for CAR, DIM and CIN respectively. The method obeyed Beer,s law in the concentration range 0.5-20 µg/ml with molar absorptivity 3.70×104, 3.43×104,  2.62×104,  and 3.53×104 l.mol-1.cm-1 for DOM, CAR, DIM and CIN respectively. The accuracy (average recovery) was ranged between 99.47 and 101.27% and precision (RSD%) is less than 3.04%. The method has been successfully applied for the determination of studied drugs in pharmaceutical formulations with no interferences. The results were in agood  agreement with certified value, official method and standard addition procedure.