Potassium‐Based Metal‐Organic Framework with Coordination‐Induced Electrochemiluminescence for Biosensing Applications
Yu Du, Min Zhu, Linlin Song, Tingting Pan, Lin Cui, Yakun Wan, Chun‐yang Zhang
Abstract
Abstract Tetraphenylethene (TPE) exhibits aggregation‐induced electrochemiluminescence (AIECL), but the achievement of high emission efficiency requires effective suppression of non‐radiative transitions. Herein, a cyclodextrin‐tetraphenylethene metal‐organic framework (CT‐MOF) is constructed that significantly enhances electrochemiluminescence (ECL) output via coordination‐induced electrochemiluminescence (CIECL). In the CT‐MOF, alkali metal ions K + coordinate with ligands comprising covalently linked amino‐ β ‐cyclodextrin ( β ‐CD) and carboxylated tetraphenylethene (TPE‐COOH), which reduces the dihedral angles of the TPE units and restricts their intramolecular rotation. The resulting rigid structure can suppress the non‐radiative pathways and generate a high ECL emission at low potential (0–1.1 V vs Ag/AgCl). Notably, the introduction of FeNi alloy‐modified graphdiyne quantum dots (FN‐GQDs) as the co‐reactant accelerators can induce further signal amplification. Taking advantage of the enhanced hydrophilicity of CT‐MOF, a nanobody‐based sandwich immunosensor is constructed for sensitive detection of tumor necrosis factor‐like cytokine 1A (TL1A), a key colitis biomarker. This work represents the first demonstration of integrating K + ‐coordinated MOFs with TL1A‐specific nanobodies for high‐performance ECL biosensing.