Determination of Dipyridamole Using a MIP-Modified Disposable Pencil Graphite Electrode

A new method for the determination of the antiplatelet drug dipyridamole (DIP) in pharmaceuticals using a molecularly imprinted polymer (MIP)-modified pencil graphite electrode (PGE) is proposed. The modified electrode was prepared simply and rapidly by electropolymerization of caffeic acid (CA) in the presence of DIP and subsequent DIP extraction with ethanol, resulting in a cost-effective, eco-friendly disposable modified electrode (MIP_PGE). Several working conditions (monomer and template concentration, number of voltametric cycles, scan rate extraction time, and solvent) for the MIP_PGE preparation were optimized. The differential pulse voltammetric (DPV) oxidation signal of DIP obtained at MIP_PGE was 28% higher than that recorded at bare PGE. Cyclic voltammetry emphasized DIP irreversible, pH-dependent, diffusion-controlled oxidation at MIP_PGE. Differential pulse and adsorptive stripping voltammetry at MIP_PGE in phosphate buffer solution pH = 7.00 were applied for the drug quantitative determination in the range of 1.00 x 10(-7)-1.00 x 10(-5) and 1.00 x 10(-8)-5.00 x 10(-7) mol/L DIP, respectively. The obtained limits of detection were at the tens nanomolar level.

Automated summary

A new method using a molecularly imprinted polymer (MIP)-modified pencil graphite electrode (PGE) is proposed for the determination of antiplatelet drug dipyridamole (DIP) in pharmaceuticals. The modified electrode (MIP_PGE) was prepared by electropolymerization of caffeic acid (CA) in the presence of DIP and subsequent DIP extraction with ethanol. The method showed higher sensitivity and lower detection limits compared to a bare PGE.