PVC Polymeric Membranes Coated Graphite Electrodes Based on Molecularly Imprinted Polymers for the Selective Determination of Glibenclamide

Abstract

Graphite coated electrodes (GCE) based on molecularly imprinted polymers werefabricated for the selective potentiometric determination of Glibenclamide (Glb). Themolecularly imprinted (MIP) and nonimprinted (NIP) polymers were synthesized by radicalbulk polymerization using (Glb.) as a template, acrylic acid (AA) and acrylamide (AAm) asmonomers, ethylene glycol dimethacrylate (EGDMA) as a cross-linker and benzoyl peroxide(BPO) as an initiator. The imprinted membranes and the non-imprinted membranes wereprepared using dioctyl phthalate (DOP) and Dibutylphthalate (DBP) as plasticizers in PVCmatrix. The membranes were coated on graphite electrodes. The MIP electrodes using (AA)and (AAm) showed a near nernstian response with slopes of -51.5±0.5and -57.8±0.1mV/decade, correlation coefficient (r2) 0.9762 and 0.9992, a linear response for aconcentration range of (1.0×10-4- 1.0×10-2) M and (1.0×10-5- 1.0×10-3) M and detection limitof 1.0×10-4M and 1.0×10-5M respectively. The response time of the prepared electrodes wasless than 30 seconds. The electrode responses were stable in a pH range (2-4). The electrodescould be successfully used within (1and 6) weeks respectively without any drift. The sensorsexhibited good selectivity over a wide range of interference. The most effective electrode wasused to determine the concentration of (Glb.) in some pharmaceutical formulations.