Selective and sensitive determination of repaglinide in pharmaceuticals by voltammetric and LC methods

Abstract

Detailed electrochemical study and novel voltammetric and LC methods are presented for the determination of repaglinide (RPG) in pharmaceuticals. Repaglinide in methanol: buffer solution (20:80; v/v) shows one or two anodic responses on glassy carbon electrode between pH 0.3 and 12.0 depending on the pH values. The HPLC and UPLC methods were developed using core shell columns with mobile phase consisting of 50:50; ACN:Water (0.05 % TFA; at pH: 3.0) (v/v) with UV detection at 215 nm. Finally, the proposed methods were successfully applied for the determination of RPG in pharmaceutical dosage forms. The proposed voltammetric and LC methods allow a number of cost and time saving benefits. RPG was also exposed to thermal, photolytic, oxidative stress, acid-base catalyzed hydrolyses, and the stressed samples were detected by the proposed RP-HPLC method.