Voltammetric characterization of a fully integrated, patterned single walled carbon nanotube three-electrode system on a glass substrate

A single walled carbon nanotube (SWCNT)-based three-electrode system was fully integrated on glass substrates using a standard microfabrication process and electrochemically characterized using cyclic voltammetry. O-2 plasma functionalization of the SWCNT film working electrode for achieving high sensitivity was voltammetrically optimized with respect to the plasma power and treatment time. Chlorination of a Ag thin-film was done in an acidic solution for different dip times to form a thin-film Ag/AgCl reference electrode. The Nernstian behavior of as-prepared and seven-day-aged Ag/AgCl thin-film electrodes was investigated for seeking the optimum reference electrode with long-term stability and was compared to a commercial reference electrode. A quality control evaluation and a performance assessment of the fully integrated SWCNT-transferred sensing systems were performed using cyclic voltammetry. The proposed SWCNT-based three electrode device exhibited clear electrochemistry under voltammetric conditions, and is therefore a candidate for use in all electrochemical biosensors.