Rod-Like Tetraphenylethylene-Based Metal–Organic Framework for Ultrasensitive Detection of Neuron-Specific Enolase

The hunt for stable and effective luminous materials has always been a major focus of investigation and research during the development of electrochemiluminescence (ECL). However, numerous challenges persist even in current times. The aggregation-induced emission (AIE) ligand 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene and La3+ were used in this study to create a rod-like metal–organic framework (La-TCBPE-MOF, LTM), which was then constructed into an inventive ECL immunosensor for the ultrasensitive detection of neuron-specific enolase (NSE). LTM showed stronger ECL signals compared to H4TCBPE aggregations, which can be attributed not only to the immobilization of H4TCBPE ligands within the rigid MOF matrix, which restricted free intramolecular rotation and vibration, but also to the reduction of nonradiative transitions. Furthermore, the loading capacity of the H4TCBPE luminophore was significantly boosted by anchoring H4TCBPE into the rigid MOF as a bridging ligand. Consequently, a larger ECL intensity was produced due to the increased amount of H4TCBPE luminophores being stimulated. As anticipated, the fabricated ECL immunosensor exhibited a broad linear range spanning from 100 fg mL–1 to 100 ng mL–1, accompanied by an impressively low limit of detection (LOD) of 21.5 fg mL–1. Moreover, the ECL immunosensor was effectively utilized for measurement in human serum. In summary, this research demonstrated a successful integration of AIE into the field of ECL, enabling rapid, sensitive, and highly precise detection of NSE.