Abstract: To improve the sensitivity of molecular imprinted electrochemical sensor, a molecularly imprinted polymer (MIP) film for the determination of phenobarbital (PB) was electropolymerized on CuO nanoparticle-modified glassy carbon electrode by using methacrylic acid (MAA) as functional monomer, ethylene glycol maleic rosinate acrylate (EGMRA) as a cross-linking agent in the presence of supporting electrolyte (tetrabutylammonium perchlorate-TBAP). The electrochemical properties of CuO nanoparticle-modified molecularly imprinted and non-imprinted polymer (NIP) sensors were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The results show that the electrochemical properties of CuO nanoparticle-modified molecularly imprinted polymer sensor were completely different with those of NIP sensors. The XRD confirmed that the nanoparticles were CuO. The morphology of CuO nanoparticle-modified molecularly imprinted polymer sensor was examined under a scanning electron microscope (SEM). The CuO nanoparticles were distributed uniformly on the surface of the modified glassy carbon electrode, and improved recognition sites of modified molecularly imprinted polymer sensor . Response value of DPV peak current shows a linear dependence on the phenobarbital concentration in the range of 1.0 x 10-8 ~ 1.8 x 10-4 mol L-1 of phenobarbital. (Linear regression coefficient = 0.9994) with the detection limit (S/N = 3) of 2.3 x 10-9 mmol L-1. The results indicated that the CuO nanoparticle-modified molecularly imprinted polymer sensor is one of the highest sensitive and selective sensors for the PB determination. The prepared sensor was successfully applied to the determination of phenobarbital in practical samples with recovery ranging from 95.0% to 102.5%.
Template and target information: phenobarbital, PB
Author keywords: CuO nanoparticles, phenobarbital, molecular imprinted polymer, electropolymerization, sensor