Inkjet-Printed Carbon Nanotube Electrodes Modified with Dimer-captosuccinic Acid-Capped Fe3O4 Nanoparticles on Reduced Graphene Oxide Nanosheets for Single-Drop Determination of Trifluoperazine

Here we report the design of a disposable single-drop voltammetric sensor for the quantitative determination of antipsy-chotic drug trifluoperazine (TFP). The sensor was build using inkjet-printed carbon nanotube (CNT) electrodes which were modified with dimercaptosuccinic acid (DMSA) coated magnetite nanoparticles uniformly dispersed over reduced graphene oxide nanosheets (DMSA/Fe3O4/RGO). The used modifying materials were characterized by electron mi-croscopies (TEM and FE-SEM), X-ray powder diffraction, zeta potential measurements, DLS and electrochemical methods (CV and EIS). Developed sensor, best operated at pH 7 in Britton-Robinson buffer solution (BRBS), shown linear electro-catalytic activity in the concentration range from 1 to 50 µM TFP, with a low detection limit of 0.54 µM and excellent se-lectivity, repeatability and reproducibility with RSD of 2.4%. A voltammetric approach using the square wave voltamme-try (SWV) was used as a sensitive technique under optimized conditions for the analytical determination of sub-micromolar amounts of TFP. Bare CNT, RGO- and DMSA/Fe3O4-modified CNT resulted in a less electrocatalytic activity then DMSA/Fe3O4/RGO/CNT electrode. The development of this kind of TFP sensor based on nanoparticles decorated graphene nanosheets can offer a tool for point-of-care applications of the sensor in biomedicine.