A glassy carbon electrode modified with N-TiO2@AgNPs@GQDs for electrochemical determination of dopamine

Abstract

In this regard, electrochemical sensors based on nanomaterials have been developed according to these requirements. In this work, N-TiO2@AgNPs@GQDs was used for designing an electrochemical sensor to measure dopamine (DA). The synthesized nanocomposites were characterized using scanning electron microscopy and infrared spectroscopy. The particle size of the synthesized nanocomposite was obtained as 30 nm using the Scherrer equation. Then, the electrochemical performance of the synthesized nanocomposite was performed by modifying the carbon glassy electrode by cyclic voltammetry and differential pulse methods. The oxidation current peak of dopamine on the surface of the modified electrode with nanocomposite “N-TiO2@AgNPs@GQDs” was 12 times that of the unmodified electrode. The results showed that the detection limit of DA was in the range of 0.003–300 μM and 1 nM. The efficiency of the electrochemical sensor for measuring DA in serum samples also shows a good recovery with 104 to 97% efficiency. The prepared sensor for dopamine measurement shows good selectivity, repeatability, and reproducibility.