Ultrafast Self-Assembled Functional Luminescent Gels: Antenna Effect-Induced Emission Enhancement and Its Biosensing Applications

The development of efficient and easily synthesized electrochemiluminescent materials is attractive but still challenging. Metal–organic gels (MOGs) are porous, soft hybrid supramolecular materials with unique optical properties. In this work, functional luminescent lanthanide organic gels (LEOGs) were synthesized by rapid coordination of lanthanide metal (Eu3+) with 2,2“:6”,2’’-terpyridine-4’-carboxylic acid (TPY). The self-luminescence behavior of LEOGs arises from the realization of the antenna effect within the molecule. According to the antenna effect, the TPY ligand is able to sensitize the central lanthanide ion by energy transfer, resulting in luminescence. On this basis, a zirconium-based organic framework (CJLU-1/Au@Pt) functionalized with gold–platinum core–shell nanoparticles (Au@Pt NPs) was used as a signal controller to regulate the emission of luminescent gel LEOGs, and the mechanism of the quenching effect between them was analyzed. In addition, we designed an “on–off” bioimmunosensor using electrochemiluminescence (ECL) generated by LEOGs as a quantitative indicator for the detection of neuron-specific enolase (NSE), a marker of small cell lung cancer (SCLC). This ECL immunosensor has good detection performance and provides a strategy and detection technique for the improvement of electrochemiluminescent materials as well as the early diagnosis of SCLC.