Development of a modified electrode with amine-functionalized TiO2/multi-walled carbon nanotubes nanocomposite for electrochemical sensing of the atypical neuroleptic drug olanzapine.

In this work, using of amine-functionalized TiO2/multi-walled carbon nanotubes (NH2-TiO2-MWCNTs) nanocomposite for modification of glassy carbon electrode (GCE) was investigated. The nanocomposite was characterized by Fourier transformed infrared spectroscopy, transmission electron microscopy and scanning electron microscopy. The efficiency of modified electrode for electrocatalytic the oxidation of olanzapine was studied by cyclic voltammetry, square wave voltammetry and chronoamperometry. The electrochemical measurements were carried out in phosphate-buffered solution (PBS, pH 5.0). The NH2-TiO2-MWCNTs/GCE provided high surface area and more sensitive performance. The charge transfer coefficient (α) and the apparent charge transfer rate constant (k(s)) were calculated to be equal to 0.42 and 0.173 s(-1), respectively. The square wave voltammetry exhibited two linear dynamic ranges and a detection limit of 0.09 μM of olanzapine. In addition, the modified electrode was employed for the determination of olanzapine in pharmaceutical and human blood serum samples in order to illustrate the applicability of proposed method.