A nano sized functionalized mesoporous silica modified carbon paste electrode as a novel, simple, robust and selective anti-diabetic metformin sensor

A novel, simple, selective and robust sensor has been developed for the electrochemical determination of metformin (MET) using anodic stripping voltammetry. The sensor was designed by incorporating of a nano sized mesoporous silica material functionalized by copper ion (SBA-15-Cu(II)) in the carbon paste electrode (CPE). The sensitivity of the sensor was improved by increasing the accumulation of MET on the surface of the electrode through complex with copper ions. The synthesized SBA-15-Cu(II) was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Under optimized conditions, the modified electrode exhibited a linear response over the MET concentration range of 0.1-65 mu M, with a detection limit of 30 nM. Also, the applicability of the method to the direct assays of the pharmaceutical and biological fluid real samples was investigated. (C) 2015 Elsevier B.V. All rights reserved.