Amperometric detection of dopamine based on tyrosinase-SWNTs-Ppy composite electrode

作者：Min Kyoungseon; Yoo Young Je^*

来源：Talanta, 2009, 80(2): 1007-1011.

DOI：10.1016/j.talanta.2009.08.032

• 3-Dimensional composite electrode
• Tyrosinase
• Chemically polymerized polypyrrole
• Single wall carbon nanotube
• Dopamine sensor
• Ascorbic acid

A novel 3-dimensional single wall carbon nanotubes (SWNTs)-polypyrrole (Ppy) composite was prepared as an electrode by chemically polymerizing polypyrrole onto SWNTs using a LiClO(4) oxidant. This composite electrode was characterized by scanning electron microscopy (SEM) and cyclic voltammetry with 1 mM [Fe(CN)(6)](-3)/[Fe(CN)(6)](-4). The SWNTs were thickly coated with chemically polymerized polypyrrole and the composite had many surface pores and crevices which could enhance mass transfer. The SWNTs-Ppy composite electrode showed a large specific surface area (30 m(2)/g) and a good reproducible current response. at about 100 times the peak current of a glassy carbon electrode (GCE). The diffusion coefficient was calculated to be 4.81 x 10(-6) cm(2)/s. As a biosensor application. tyrosinase was immobilized on the functionalized SWNTs and tyrosinase-SWNTs-Ppy composite was prepared in the same manner. This tyrosinase-SWNT-Ppy composite electrode was used for amperometric detection of dopamine in the presence of ascorbic acid and showed high sensitivity (467 mA/M cm(2)) and lower detection limit (5 mu M) compared to previous reports.

• 出版日期2009-12-15