A simple, fast and sensitive spectrophotometric method has been developed for the determination of esomeprazole in its pure form and also in the form of a pharmaceutical preparation. The highest absorption was found at a wavelength of 618 nm and the limits of Beer were (2_24) µg/ml. The molar absorbance (2.1070 ˣ104) L.mol-1 .cm-1, Sandell sensitivity 0.016 µg.cm-2, and limits of detection LOD 0.0153 µg/ml, LOQ 0.0510 µg/ml were determined the method was also applied to pharmaceutical preparations, and the validity of the method was confirmed by standard addition.

The aim of the following study is to develop a sensitive, high-accuracy and fast spectrophotometric method for the determination of esomeprazole (ESO) in pharmaceutical preparations.The proposed method is based on the formation of dyzonium salt from the reaction of meta-aminophenol reagent with nitrite in an acidic medium and then coupling it with esomeprazole in an alkaline medium to form a yellow dye that gives the highest absorption at a wavelength of 450 nm. Obtaining a calibration curve within 1_12 with a correlation coefficient of 0. 999. The molar absorbance 3.3954 × 104 L.mol-1 .cm-1, Sandell sensitivity 0.0101 µg.cm-2, and limits of detection LOD 0.048 µg/ml, LOQ 0.161 µg/ml were determined. The method was also applied to pharmaceutical preparations, and the validity of the method was confirmed by standard addition.