Bimetallic electrocatalyst synergistic effect boosts aggregation-induced electrochemiluminescence of gadolinium-based metal-organic framework for sensitive quantitation of anti-müllerian hormone.

This study presents the synthesis of a gadolinium-based metal-organic framework (Gd-MOF) via coordination between Gd3+ ions and 1,2,4,5-tetrakis (4-carboxyphenyl) benzene (H4TCPB). Gd-MOF demonstrated pronounced aggregation-induced electrochemiluminescence (AIECL) performance. With potassium persulfate (K2S2O8) as a co-reactant, Gd-MOF exhibited a significantly stronger and more stable cathodic electrochemiluminescence (ECL) response, with improved ECL efficiency compared with the H4TCPB ligand alone. Moreover, the introduction of the copper‑iron Prussian blue analogue (CuFePBA) as an electrocatalytic co-reaction accelerator significantly enhanced the ECL performance of Gd-MOF. CuFePBA exhibited high electrocatalytic activity owing to the efficient redox cycling of Cu2+/Cu+ and Fe3+/Fe2+, which facilitated the conversion of K2S2O8 into SO4•- radicals. By integrating these signal amplification strategies, we developed an ECL immunosensor using Gd-MOF and CuFePBA for the sensitive quantitation of anti-Müllerian hormone. The immunosensor demonstrated a linear ECL response across a wide range (10 fg/mL to 100 ng/mL) and achieved a low detection limit of 2.7 fg/mL. Overall, this study successfully combines AIECL with electrocatalytic amplification strategies, thereby significantly enhancing the ECL performance of polycyclic aromatic hydrocarbon emitters. The research provides a promising approach for developing high-performance organic ECL emitters.