Enhanced electrochemiluminescence sensor for detecting dopamine based on gold nanoflower@graphitic carbon nitride polymer nanosheet–polyaniline hybrids

Abstract

In this work, an enhanced electrochemiluminescence (ECL) sensor based on gold nanoflower@graphitic carbon nitride polymer nanosheet–polyaniline hybrids (AuNF@g-C₃N₄–PANI) was prepared for the detection of dapamine (DA). First, the bulk g-C₃N₄ was prepared through polymerizing melamine under 600 °C. And then the g-C₃N₄ nanosheet was obtained by ultrasonication-assisted liquid exfoliation of bulk g-C₃N₄. Finally, polyaniline (PANI) and gold nanoflowers (AuNFs) were successively formed on the g-C₃N₄ nanosheet through an in situ synthesis method. The resulting AuNF@g-C₃N₄–PANI hybrids were modified onto the surface of glassy carbon electrode to achieve a sensor (AuNF@g-C₃N₄–PANI/GCE) for detecting dopamine. Under the optimal conditions, the ECL signal increased linearly with the concentration of dopamine. The linear range of 5.0 × 10⁻⁹ to 1.6 × 10⁻⁶ M was obtained, while the detection limit was 1.7 × 10⁻⁹ M. The prepared sensor exhibited a low detection limit and high sensitivity for the determination of dopamine. The combination of g-C₃N₄ nanosheet, PANI and AuNF would provide a new opportunity for the ECL sensor.