Electrochemical determination of antihypertensive drug irbesartan in pharmaceuticals

A sensitive voltammetric method has been developed for the determination of irbesartan in a Britton-Robinson buffer medium. Irbesartan exhibited a well-defined cathodic peak over the entire pH range from 2.0 to 12.0. The mechanism of reduction was postulated on the basis of controlled potential electrolysis, coulometry, and spectral analysis. Under optimal conditions, a linear response of irbesartan was obtained in the range from 3.0 × 10−5 to 5.7 × 10−3 mol L−1 and with a limit of detection of 5.33 × 10−7 mol L−1. The effect of cationic surfactant on the voltammetric reduction peak of irbesartan in Britton-Robinson buffer is also described.