Fabrication of Tiron Doped Poly-Pyrrole/Carbon Nanotubes on Low Resistance Monolayer-Modified Glassy Carbon Electrode for Selective Determination of Dopamine

Abstract

In this paper, we described a novel sensor based on tiron-doped polypyrrole and carbon nanotubes (CNTs) fabricated on low resistance monolayer-modified glassy carbon electrode. First, the dodecylamine monolayer was chemically modified. Second, CNTs were controllably adsorbed onto dodecylamine. Then, tiron doped polypyrrole was electro-deposited on the CNTs film. The layer-by-layer modified electrode was sensitive to dopamine, while it made no response to even high concentration of ascorbic acid. Parameters influencing the dopamine response were optimized. High performance of the sensor was obtained, such as wide concentration range, low detection limit (3 nM), low background current, high stability, and reproducibility.

Keywords:

• Carbon nanotubes
• Dopamine
• Low resistance monolayer
• Oxidative adsorption
• Tiron doped polypyrrole

Acknowledgments

The financial support from National Outstanding Youth Foundations of China, National Science Foundation of China (50725825) and Special Research Found for the Doctoral Program of Higher Education of China (20060532006) is acknowledged.

Notes

^a poly N-Acetyltyramine.

^b sulfobutylether-β-cyclodextrin.

^c boron-doped diamond.

^d overoxidized-polypyrrole.

^a Average of five determinations ± standard deviation.

^b Current ratio = (response current to DA in the presence of interferents)/(response current to pure DA).