An electrochemical dopamine aptasensor using the modified Au electrode with spindle-shaped gold nanostructure

In this study, a novel electrochemical dopamine aptasensor was developed. Spindle-shaped gold nanostructure was used to find an optimized surface for aptamer immobilization. The used nanostructure was studied through field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS). Electrochemical measurements were based on differential pulse voltammetry (DPV). Methylene blue (MB) was used as a redox marker during experiments. In order to find real selectivity of the designed aptasensor, ascorbic acid, epinephrine, norepinephrine, catechol and uric acid were used as interfering agents in the presence of dopamine. This aptasensor could detect dopamine in the linear range 25 pg mL−1–3 ng mL−1 with the limit of detection (LOD) of 2 pg mL−1.