Characterization of dodecanethiol SAM and multi-walled carbon nanotube modified gold electrodes, and voltammetric determination of prochlorperazine

A multi-walled carbon nanotube and dodecanethiol (DDT) modified gold electrode (i.e. MWNTs/DDT/Au) was prepared and characterized. When the gold electrode was modified with a DDT self-assembled monolayer (SAM) followed by a MWNT film, the electrode area increased by a factor of about 4. At the same time, the blocking action of the DDT SAM with respect to electron transfer disappeared. The conductivity of MWNT wires imbedded in the DDT SAM was thought to account for that. The resultant electrode was more stable than MWNTs/Au and more sensitive than MWNTs/GC. At the MWNTs/DDT/Au, prochlorperazine exhibited two anodic peaks at about 0.69 V and 0.88 V in pH 5.8 phosphate buffer solution. The peak at about 0.69 V was suitable for prochlorperazine determination. After an accumulation time of 180 s in an open circuit, the peak current was linear to prochlorperazine concentration over the range of 5 x 10(-7) M-1.5 x 10(-5) M with correlation coefficient of 0.995; the detection limit was 1 X 10(-7) M. Compared to DDT/Au, this electrode regenerated easily by repetitive cycling in a blank solution.