Ternary Pt–Au–FeOOH-decorated polyaniline nanocomposite for sensitive dopamine electrochemical detection

Electrochemical dopamine sensing is crucial for neurological diseases, but its practical application is challenged by sensitivity and anti-interference. Pt-decorated polymer electrode is desirable for dopamine sensing, but its unsatisfactory sensitivity, anti-poisoning capability, and stability limit its application. A new ternary Pt–Au–FeOOH-decorated polyaniline (PANI) nanocomposite (PANI/Pt–Au–FeOOH) modified electrode was successfully fabricated for dopamine (DA) detection. The electrochemical response of DA on PANI/Pt–Au–FeOOH-modified electrode obtained by differential pulse voltammetry (DPV) showed higher electrocatalytic activity than its contrastive unitary and binary Pt-decorated PANI nanocomposites. Analysis of DPV performance for PANI/Pt–Au–FeOOH-modified electrode showed a wide bilinear response of 10–200 and 0.001–10 μM, a low limit of detection (LOD) of 1 nM (0.001 μM), and outstanding anti-interference and stability. Human serum experiment revealed PANI/Pt–Au–FeOOH as a potential sensing electrode and indicated its high detection accuracy for DA. The PANI/Pt–Au–FeOOH also showed its advantage for UA detection. The remarkable advantages of its analytical performance for ternary Pt–Au–FeOOH may be ascribed to the tuning electronic structure and chemical properties of Pt by adjacent metal atoms. This work provides a new choice for the fabrication of advanced Pt-based nanocatalysts with enhanced electrochemical activity.