In situ fabrication of Cu2O array electrode for efficient detection of acetaminophen

In this paper, [Formula: see text] nanosheet arrays were directly grown in an upright manner on the surface of copper foam (CF) through a simple solvent reaction, followed by the successful reduction of [Formula: see text] into [Formula: see text] using hydrazine hydrate vapor, resulting in a binder-free [Formula: see text] array electrode. The in situ growth technique guarantees robust bonding between [Formula: see text] and the conductive substrate, thereby enhancing electron transfer among various electrode components. Additionally, the vertically aligned array structures facilitate rapid penetration and transfer of the analyte, while also allowing for thorough exposure of the electroactive surfaces to the electrolyte. When utilized as an adhesive-free biosensor, the obtained [Formula: see text] array electrode exhibited sensitive catalytic oxidation activity toward acetaminophen (AP), providing a wide linear range of 2–200 [Formula: see text]M and a low detection limit of 0.6 [Formula: see text]M for AP detection. Furthermore, the developed [Formula: see text] array electrode was successfully utilized to detect AP in medicine samples. With its simple fabrication method, broad linear range, low detection limit, and excellent stability, this electrode holds significant promise for the detection of AP in pharmaceuticals.