Development of a highly selective and sensitive electrochemical sensor for Bi~(3+) determination based on nano-structured bismuth-imprinted polymer modified carbon/carbon nanotube paste electrode

摘要

A new nano-structured bismuth(Ⅲ)-imprinted polymer was prepared by copolymerization of Bi(Ⅲ)-methylene succinate complex and ethylene glycol dimethacrylate in acetonitrile via precipitation polymerization technique. The polymeric nanoparticles were then used as the Bi~(3+) selective modifier of a carbon/carbon nanotube paste electrode. Bismuth ions were accumulated on the surface of the electrode, immersed in the Bi~(3+) solution for a definite time. Then, the anodic striping differential pulse voltammetric signal of the modified electrode was recorded as analytical signal which was significantly higher than that recorded by the non-imprinted polymer based electrode, at the same experimental con ditions. Compared to the previously reported carbon paste electrodes, this sensor was more selective, regarding potential interfering species of Cu~(2+) and Ag~+. The electrode exhibited a dynamic linear response range of 0.2-2 μmol L~(-1) and detection limit of 8.9 nmol L~(-1) for Bi~(3+) measurement. The sensitivity of the sensor was 112.25 μAμM~(-1), indicating an excellent sensitivity of the developed sensor. The sensor was successfully applied for the electrochemical determination of Bi~(3+) ions in environmental, pharmaceutical and biological samples.