Spectrophotometric Assay of Noradrenaline in Pharmaceutical Formulation with Alizarin Red Sulphonate

ABSTRACT<br /> A simple, rapid and sensitive spectrophotometric method for the determination of noradrenaline was developed. The method is based on the proton transfer reaction with alizarin red sulphonate (ARS) in aqueous neutral solution to form violet product showing maximum absorbance at 530 nm with molar absorptivity of 6720 l.mol-1.cm-1. The method follows Beer’s law over the concentration range (0.5-10) g.ml-1. The accuracy (average recovery) of the method is 100.29% and the precision (RSD) of the method is less than 1%.<br /> The method was successfully applied for the determination of noradrenaline in pharmaceutical formulation as injection and the results were in good agreement with the standard addition procedure.