2D Zn-based metal-organic framework as an efficient electrochemiluminescence emitter: A novel inner filter...

The potential hazards of bisphenol A (BPA) to the environment have become a global concern. Herein, 2D Zn-based metal-organic framework nanosheet (2D Zn-MOF) and MnCO₃ nanocomposite (Zn-MOF-MnCO₃), an efficient electrochemiluminescence (ECL) probe was first synthesized and constructed for trace detection of BPA. Owing to the elimination of the aggregation-induced quenching (ACQ) effect of polycyclic aromatic hydrocarbons (PAHs), the leaf-like Zn-MOF exhibited a satisfactory ECL signal. The MnCO₃, which has excellent biocompatibility, showed excellent ECL efficiency in the presence of K₂S₂O₈. With the covalent binding of Zn-MOF and MnCO₃, we demonstrated that the ECL intensity and stability of Zn-MOF-MnCO₃ improved significantly. In addition, the inner filter effect (IFE) of Fe₃O₄-NH₂ NPs toward Zn-MOF-MnCO₃ had been confirmed to be the ECL quenching mechanism. Based on above strategies, the proposed ECL-IFE biosensor exhibited a trace detection ability of BPA in a wide linear range (10 fM ∼ 10 μM) with a low detection limit (4.2 fM). Further in-depth study confirmed the excellent repeatability, selectivity, and stability of sensors, which provided a fresh sensing platform for trace detection of BPA in the environment.