Facile fabrication of Fe-Fe3C nanoparticles decorated with carbon nanotubes for sensitive dopamine detection

In this study, we present an electrochemical sensor with superior sensitivity and selectivity for dopamine (DA) detection. The sensor was created using a nanocomposite of iron-iron carbide nanoparticles decorated with carbon nanotubes (Fe-Fe3C@CNTs) to modify a glassy carbon electrode (GCE). The Fe-Fe3C@CNTs nanocomposite can be synthesized by a facile microwave-assisted synthesis method with just adopting ferrocene and carbon fiber as raw material and heat source, respectively. The electron microscopy (EM) results indicate that the Fe-Fe3C nanoparticles encapsulated with graphitic layer were decorated with CNTs. An investigation of the electrochemical responses of the Fe-Fe3C@CNTs/GCE sensor to DA was performed using both cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Notably, in ideal experimental settings, the sensor demonstrated a minimal limit of detection (LOD) of 0.01 μM within a range of linearity from 0.05 to 40 μM, even under a high concentration of uric acid (UA) interference. Moreover, the utility of the produced Fe-Fe3C@CNTs/GCE sensor was further validated through successful DA testing in urine samples of human.