Electrochemistry of raloxifene on glassy carbon electrode and its determination in pharmaceutical formulations and human plasma

The electrochemical behavior of raloxifene (RLX) on the surface of a glassy carbon electrode (GCE) has been studied by cyclic voltammetry (CV). The CV studies were performed in various supporting electrolytes, wide range of potential scan rates, and pHs. The results showed an adsorption-controlled and quasi-reversible process for the electrochemical reaction of RLX, and a probable redox mechanism was suggested. Under the optimum conditions, differential pulse voltammetry (DPV) was applied for quantitative determination of the RLX in pharmaceutical formulations. The DPV measurements showed that the anodic peak current of the RLX was linear to its concentration in the range of 0.2-50.0 mu M with a detection limit of 0.0750 mu M, relative standard deviation (RSD %) below 3.0%, and a good sensitivity. The proposed method was successfully applied for determination of the RLX in pharmaceutical and human plasma samples with a good selectivity and suitable recovery. (C) 2012 Elsevier B.V. All rights reserved.